Tags: intermittent-fasting

Seth Roberts and the Shangri-La Diet

I cite Seth Roberts’ blog a great deal over at Linked Down. Seth is a Psychology Professor at Berkeley and an avid self-experimenter. I’ve learned a great deal from subscribing to his blog.

For those who don’t know, Seth Roberts created the Shangri-La Diet, which is a diet centered around reducing the association between flavor and caloric load. I haven’t read the book, so this is an approximation of how it works, but the gist is that the more correlated taste is to caloric load, the greater hunger can be, the harder it will be to cut calories, and the higher your body’s set point for weight will be. “SLD” hacks this relationship via ingesting flavorless calories within certain windows of time. These flavorless calories reduce the brain’s association of high energy density and high flavor. Interestingly enough, the macronutrient source of the calories may be unimportant: you can do SLD with oil, sugar water (so long as it is flavorless), or nose-clipping while eating protein. If you’re skeptical about this diet, I suggest taking a trip over to the SLD Forums and be prepared to see plenty of evidence that SLD works.

Even as I have not tried SLD, it is a fascinating idea and it seems that anyone who is serious about better understanding why we gain weight and what regulates hunger and adiposity must take it seriously enough to figure out how it fits into the big picture of human health. Barring that gargantuan task, it’s at a minimum another way to try and hack weight loss if your current regiment isn’t cutting it for you.

I mention all of this because I stumbled on a 2008 interview between Roberts and Gary Taubes, author of Good Calories, Bad Calories, which I’ve blogged about exhaustively. What a great thing to find that two people I admire had a thoughtful discussion and, even better, said discussion has been made available to me?

Blogging, science and the internet FTW.

Back to trying to understand how SLD fits into the grand scheme of human physiology. An interesting comment was made at the bottom of Part 13 of Roberts’ Interview of Gary Taubes:

I’ve thought a lot about how consuming tasteless food could supress hunger. My favorite theory is that it is similar to what happens when an animal is hibernating. The “magical” appearance of calories fools your body into thinking it is living off its fat and then it actually does so.

This comment reminded me of how the metabolic pathways while fasted are the same as when we consume a diet of only fat and protein. One effect of low-carb diets is appetite suppression. Could the common theme here simply be that both SLD and low-carbohydrate diets and/or fasting act to “trick” our bodies into switching to a non-hungry state?

Obviously that can’t be the entire picture because insulin is the storage hormone that is unleashed by carbohydrate consumption (though less so with fructose).

This issue is worthy of further thought.

PermalinkPermalink Thursday April 23 at 10:24:27 am, by Justin — 1 comment »

Understanding Bodyweight and Glycogen Depletion

Quick take — If you diet or are planning to start a diet, understanding the relationship between bodyweight and glycogen (Glycogen is carbohydrates as stored by your body) depletion is paramount.

Your body stores energy as fat and glycogen. Whereas fat stores can vary dramatically from person to person, your body can only store so much energy as glycogen.

Glycogen requires water to be stored. In the initial stages of diet/caloric restriction and exercise, your body depletes these glycogen stores, reducing your bodyweight from the elimination of both the weight of the stored glycogen and the weight of the water. Note that nowhere in this process is the much-desired loss of fat!

Thus, even as it will feel good to shed 5 - 10 lbs. simply from a few days of exercise mixed with a caloric-restricted diet, the weight loss will be primarily from a reduction in glycogen stores and water. In other words, what you’ll have lost in the beginning is really little more than water weight.

Take heart in understanding the relationship between glycogen stores and bodyweight as an improved understanding will help you set realistic expectations on whatever diet or exercise regiment you are undertaking in 2009.

A deeper dive:

I first learned about the relationship between stored carbohydrates and water retention from Gary Taubes’ Good Calories, Bad Calories. The gist is that for every gram of stored carbohydrate (Stored as glycogen) in your body, there is a set amount of additional water storage that is required.

Taubes had pinned the carb/water storage ratio at two grams of water per one gram of carbohydrate. A random Googled source pins it at 2.7 gram water per gram of glycogen. I found a research paper titled, Glycogen storage: illusions of easy weight loss, excessive weight regain, and distortions in estimates of body composition, which offers the following data on the ratio:

Glycogen is stored in the liver, muscles, and fat cells in hydrated form (three to four parts water) associated with potassium (0.45 mmol K/g glycogen). . . .

Glycogen losses or gains are reported to be associated with an additional three to four parts water, so that as much as 5 kg weight change might not be associated with any fat loss.

Lyle McDonald of Body Recomposition has also weighed in on this subject:

Carbohydrate (stored in your muscles and liver as glycogen) is accompanied by a good bit of water. For every gram of glycogen stored, you store anywhere from 3-4 grams of water with it.

How does this relationship affect bodyweight? In short, diet and exercise will deplete glycogen stores. If your diet is working, the depletion will occur early and have a significant impact on your bodyweight without impacting a permanent change in your body composition.

Let’s take me as an example. I estimate that I have around 155 - 160 pounds of lean tissue. Tack on another 12 - 17 pounds of fat. After a week or two of being on a low-carbohydrate diet that involves intermittent fasting and plenty of exercise (see here), my liver and muscle glycogen stores will be completely depleted. I’ll weigh about 172.

If I go on to eat a bunch of carbohydrates — cookies, pretzels, breads, fruits and other starchy foods (by eating a bunch, I mean consuming something on the order of 1000 grams of carbohydrates over the course of 24 hours, which is about 4000 calories), I will fully replenish my glycogen stores. In the process of replenishment, the 1000 grams of carbohydrates will require anywhere from 3000 to 4000 grams of water for storage! Converting from grams to pounds, the impact on my bodyweight should be an increase of 9 to 11 pounds, taking my weight up to 183*! Of course, the same change would happen in reverse: re-depleting glycogen stores would drop my weigh back to the low 170s.

Mike over at the IF life alluded to this fact in three bullets back on his Trainer Tells All post:

Muscle size is mostly glycogen and water . . . I can go up and down 10lbs in a week easily depending on glycogen and water balance . . . The first big amount of lbs you lose in the first week dieting is mostly water

Mike’s anecdotal experience is explained by the storage ratio between glycogen and water. What it means is that in the early stages of a diet, the magical drop in bodyweight will be mostly water weight.

Another implication of the water/glycogen relationship on bodyweight is that whereas the first 4000 calorie deficit you create will reduce your weight some ten pounds, the next 4000 calorie deficit is likely only going to reduce your bodyweight a paltry two pounds! This is because a pound of fat stores 3500 calories and requires about a pound of water for storage. Thus, the initial weight-loss will seem easy compared to the drudging continued weight-loss when you’re actually burning stored fat.

Failing to understand what is going on with glycogen stores and water retention will set yourself up for a shock when you inevitably “fall off the wagon” – even if the “fall” is only for a day or two of heavy-carb or more “normal” eating.

Understanding the impact of glycogen depletion/repletion on bodyweight is just one more reason why merely weighing yourself on a scale provides a poor indication of your body composition. You’re better served by taking some physical measurements (waist size, for example). Or even better, take some periodic camera phone self-portraits — over time, you should be able to compare them and get a great feel for your progress (or lack thereof).

* I’ve witnessed this fluctuation on numerous occasions over the past year, but I didn’t quite fully understand it until today. You see, I was fully glycogen depleted going into New Year’s Eve. I proceeded to go on a pre-planned “refeed” (that just happpened to coincide with NYE, of course!). The refeed involved eating plenty of pretzels, chips, breads, fruits, cookies, cereal, donuts, etc. Some incredibly unhealthy, albeit tasty, foods. I also drank a good bit of Pinot Noir NYE, which is the opposite of what you should do if you are re-feeding in that your body will be needing water and alcohol will dehydrate you past certain levels of intake. Anyway, after a 24 hour refeed, my bodyweight went from 172 to 184. Hard to believe unless you understand what is going on. And this kind of fluctuation would be entirely disheartening to the ignorant dieter who might feel they just blew their diet in one day! As it is, I expect I’ll be back in the low 170s within five days after I do a fast and get two or three workouts in.

Further reading:

PermalinkPermalink Friday January 02 at 02:44:04 pm, by Justin — 8 comments »

Sugar on the brain

Is sugar another addictive white powder?

A recent study suggests sugar may be addictive. Below are parts of the U.S. News article summarizing the experiment and interpretation of the findings. I suggest reading them all:

“Our evidence from an animal model suggests that bingeing on sugar can act in the brain in ways very similar to drugs of abuse,” [said] lead researcher Bart Hoebel . . .

“Drinking large amounts of sugar water when hungry can cause behavioral changes and even neurochemical changes in the brain which resemble changes that are produced when animals or people take substances of abuse. These animals show signs of withdrawal and even long-lasting effects that might resemble craving,” . . .

A “sugar addiction” may even act as a “gateway” to later abuse of drugs such as alcohol . . .

For the new research, rats were denied food for 12 hours a day, then were given access to food and sugar (25 percent glucose and 10 percent sucrose, similar to a soft drink) for 12 hours a day, for three to four weeks.

The bingeing released a surge of the neurotransmitter dopamine each time in the part of the brain involved in reward, the nucleus accumbens. “It’s been known that drugs of abuse release or increase the levels of dopamine in that part of the brain,” Hoebel said.

But it wasn’t only the sugar that caused this effect, Hoebel explained – it was the sugar combined with the alternating schedule of deprivation and largesse. . . .

But longer periods of abstinence didn’t “cure” the rats. Instead, there were long-lasting effects with the animals: They ingested more sugar than before, as if they were craving the substance and, without sugar, they drank more alcohol.

My anecdotal experience confirms the above findings. For one, the more I have abstained from sugar and refined carbohydrates (the latter of which are one tiny step away from being sugar), the easier it has become to strictly avoid sugar/carbohydrate-dense foods. This suggests to me that the addiction can be controlled by almost completely abstaining from the “drug,” sugar in this case.

Of note, however, is that in those instances when I have fallen off the wagon* and started eating sugar/refined carbs, I tend to overeat/binge. Is this the behavior of an addict? Or is it the psychological response to the forbidden fruit? Or is it a predictable response of treating a diet like a binary system? I.e. going from strict adherence to the diet to “Well I already ate that candy, might as well have some ice cream, too!” Any of these are plausible explanations for my behavior.

The alcohol angle is fascinating: I’ve experienced a clear connection between alcohol and carbohydrate-binge-eating. As before, I am unclear how the alcohol is catalyzing my reaction — is it that alcohol impairs my judgment, handicapping my will power? Or could it be more fundamentally metabolic — the alcohol spurs a chemical reaction resulting in craving sugar/refined carbohydrates? Why do I go from having little-to-no craving for French fries and tator tots to no-holds-barred “pass the ketchup now!” after downing three or four beers.

I have previously blogged on how hard liquor has zero carbohydrates. I’ve since learned that hard liquor (i.e. whiskey) will cause an insulin response even though there are no carbohydrates in the alcohol. Could insulin have something to do with this#?

This study, rather than confirming something I’ve suspected about the addictive nature of sugar, leaves me with more questions than answers. Is modern man doomed to be addicted to sugar? Is sugar addiction similar to alcoholism in that the only successful means to control the addiction is to avoid entirely the addictive substance? Can abstaining from sugar/refined carbohydrates make the addiction worse? Is sugar a poison that should be taken in small doses to control its ill-affects (A particularly strange notion)?

It seems there are more questions than answers. However, I maintain that sugar in any close-to-raw form is unnatural, which means that our evolutionarily designed bodies are inept at handling it. And it seems reasonable to conclude that, even if I tend to overeat refined carbohydrates when I do consume them, over the long-term, I’m still drastically reducing my intake of sugar and refined carbohydrates by maintaining a lifestyle focused on a low-carbohydrate, natural diet mixed with intermittent fasting.

* How often have you heard the phrase “fallen off the wagon” to describe failure at dieting? I hear it all the time (and use it). Probably just a coincidence, this phrase originates in alcoholism. Here we have a study that paints sugar as being similar to alcohol in its addictive characteristics.

# I can’t help but wonder if insulin is the culprit behind addiction to both alcohol and sugar. Has anyone looked into this?

Permalink Day 345 of Week 50 — Email , 788 words, 2218 views
Categories: eating, health
Tags: addiction, alcoholism, carbohydrates, eating, fasting, health, intermittent-fasting, low-carb, refined-carbohydrates, sugar
PermalinkPermalink Thursday December 11 at 03:58:23 pm, by Justin — 2 comments »

Back to basics: Fasting and Fasted workouts

Having returned from India and a month-long hiatus from eating healthy and working out, I started brewing on a strategy to “get back at it” and continue working to my ultimate goal, which is achieving never-before-seen (on me) lean-ness and vasculature.

My approach for most of the summer had been working out about five days a week (doing CrossFit) with daily fasting (i.e. 16 hour fasts daily). I tracked a lot of my daily workouts via my workout blog.

Unfortunately, I ran into any number setbacks as I had a couple long periods where I couldn’t manage to eat right or workout (A two week stint out west and a three week stint in India).

That brings me back to today. I’m going “back to basics,” which for me, was eating breakfast/lunch and the fasting until dinner the following day, with a weight-lifting oriented workout an hour or two before breaking my fast. This method worked for me the first time, stripping away a great deal of fat and focusing my diet/weight-training efforts. This time around, the only tweak I’m implementing is that I will do two fasts per week, lifting on days I break the fast, working out on days I eat, and resting on any day I begin a fast. Per usual, my diet will be carb-light, which means no breads, rices, cereals or starchy vegetables while still allowing for most fruits (apples and berries being preferred), some cheats (ice cream), and alcohol.

Goal is to try this for three weeks, track my progress daily and see how I come out on the other end. Stay tuned.

Permalink Day 316 of Week 46 — Email , 271 words, 997 views
Categories: eating, health, exercise, liveblogging
Tags: exercise, fasting, health, intermittent-fasting, leaning-out, vasculature, weight-lifting, working-out
PermalinkPermalink Wednesday November 12 at 11:29:12 am, by Justin — 3 comments »

"Insulin Control" - what it's all about!

I subscribed to Mike OD’s The IF Life1 awhile back. Mike is a personal trainer with years of experience who is a big advocate of incorporating intermittent fasting into your life. However, his site isn’t merely about IF. From what I can tell, the IF Life aims to be a holistic resource on living a healthy and happy life. Mike’s site is a great resource — check it out.

In two recent posts on The IF Life, Mike used the phrase “insulin control” to sum up one of the key tenets of effective diets (See here and here).

In the first post, Mike alludes to the fact that insulin control is the chief goal of all effective diets, whether the diets know it or not (I.e. diets that advocate six meals a day are aiming to control insulin spikes, even if they don’t say so explicitly).

In the second linked post, titled Diet Book Insanity. When did Eating become this Complicated?, Mike states:

Now I know what many may say, but diets can work right? Sure … at the heart of all diets you see 2 main things that will get people results: Insulin control (see the carbs are not the enemy post and insulin and sugar post) and Calorie Deficit Intake (so the body burns from internal fuel sources, which is what you need if you want to burn that stubborn body fat).

Mike smartly tacks on caloric restriction to insulin control as the two overarching diet-advice mantras that tend to get results (Almost certainly so when used together). And though this wasn’t really the point of his diet insanity post (and I know I didn’t coin the phrase), I’m still going to take some credit for distilling the diet madness down to two simple words:

They’re all about insulin control!

Update 09/10/08: Robb Wolf, another blogger I’m subscribing to these days, happened to use the phrase “insulin control” back in October of 2007:

Super simple: Our nutritional recommendations are focused at insulin control. You could also say that our nutritional recommendations are what we are designed to eat and thrive on …

The post is about CrossFit, overexercising, and dialing in nutrition in order to see body composition changes. In my (limited) experience, his post rings absolutely true for me: exercise did little in the way to improve my body composition until I reigned in insulin.

1 “IF” stands for “Intermittent Fasting", of course, and you gotta love the play on words the acronym creates!

Permalink Day 252 of Week 37 — Email , 412 words, 1146 views
Categories: health
Tags: caloric-restriction, diet, diets, food, health, insulin-control, intermittent-fasting, low-carb, low-carbohydrate-diet
PermalinkPermalink Tuesday September 09 at 06:09:17 pm, by Justin — 4 comments »

Being healthy on the road

Traveling has an uncanny tendency to thwart healthy routines. It is difficult both to make time for exercise and to eat healthy amidst the bevy of fast food restaurants, hotels, free food, abundant spirits and people who eat differently than me. How do you navigate these health obstructions while on the road?

I’m hardly an expert, but here is how I’m managing to maintain a low-carb diet replete with activity while being away from home:

  • Be active. Some Hollywood star has the following motto: “I try to break a sweat everyday.” (H/T IF Life) This just seems like a robust life-motto that reverberates in my head — a life where you exert enough effort to break a sweat every day just seems right to me.

    On the road, it can be difficult to do this with limited equipment. I like having a kettlebell around, but if you’re flying, you can forget about taking a 35 lb. or 53 lb. kettlebell along for the ride.

    This means you have to improvise. Good ways I’ve found to improvise include running sprints, doing push-ups, and air squats. I’m still trying to find a good pull-up substitute that can be performed with everyday furniture (Any ideas?).

  • Skip a meal or two. Fasting is such a powerful tool to recenter/refocus after finding yourself lost in the bad habits that result from traveling. I’ve found the easiest way to fast is to skip breakfast. Depending on how you’re feeling around lunchtime, feel free to skip lunch, too. I did this yesterday, not eating anything until dinner and I felt great all day and even managed a nice workout compliments of a treadmill and one of those all-in-one weightlifting machines (Improvise!).
  • Go for level-two fast food. I just made up that Level II distinction. What I mean by it is that you should take the extra ten minutes to seek out local restaurants that can serve up some healthier takeout dishes. For me, I’ve eaten a few greek salads with gyro meat or chicken. It’s not ideal but its better than getting a number five combo from McDonald’s.
  • Don’t strive for perfection. When you inevitably cave to cravings and eat that fresh-baked cinnamon bun that was calling your name at the hotel breakfast bar, let it go. Striving to acheive a perfect maintenance of your healthy habits while on the road is a recipe for failure. It’s okay to deviate — just take steps to get back on track (i.e. trying a mini-fast or having an intense workout in the hotel gym).

So that is what I’ve come up with so far. I’m interested to hear any ideas from any readers regarding other ways to be healthy “on the road". Please comment if you think of something you’d like to share!

Finally, one of the hardest parts about breaking routines is getting back on track after the traveling is over. That topic remains a discussion for another day: though I will say that I’ve found fasting to be an excellent way to “re-rail” post-vacation.

Permalink Day 205 of Week 30 — Email , 508 words, 571 views
Categories: eating
Tags: eating, exercise, fast, fasting, healthy-habits, intermittent-fasting, low-carb, on-the-road, vacation
PermalinkPermalink Thursday July 24 at 02:29:38 pm, by Justin — Leave a comment »

Insulin Control: The Common Denominator of the Low-Carb / Fasting / Caloric Restriction Diets.

Over the past four months, I’ve turned into a staunch advocate of Paleo / low-carb / intermittent fasting (See IF/low-carb, caloric restriction, ketosis, hormesis). I proselytize because this diet lifestyle has had a significant impact on my physical health and my understanding of nutrition. Unfortunately, it wasn’t long before my advocacy spurred the comment that there is “No zealot like the converted.” Oof!

The retort stuck with me. I am a passionate about spreading good ideas. And this idea concerning the health of my friends and family was not only a good idea in theory, but also one in practice. The last thing I wanted was for my zeal to turn individuals away. I needed a better in than “low-carb” or “fasting".

Unfortunately, there are a lot of pre-conceived notions and pent-up negative biases towards “low-carb” in specific and diets in general. Most people have experienced nothing but disappointment from dieting and/or strict exercise regiments. When the low-carb meme went mainstream a few years ago, non-believers and skeptics rightfully vocalized their doubt. My own curiosity brought me to read a good portion of Atkins New Diet Revolution; however, I was unconvinced. Atkins’ rhetoric was all pathos and little ethos: I needed the science. Not surprisingly, I never even tried the diet, more or less writing it off as just another fad.

Fast-forward to today. There is an ever-growing number of branded low-carbohydrate diets, and additionally, there are a growing number of diets that incorporate caloric restriction or fasting (Popular examples of low-carb and/or fasting include Paleo / DeVany, Protein Power, Atkins, South Beach, Warrior Diet, The Zone, Eat Stop Eat, Fast-5, UpDayDownDay, Bantingism, etc.). Such a plethora of similar yet nuanced regiments is confusing. Who wants to wade through them all to explain their own method? Who wants to lay caveat upon caveat on a diet to tailor fit it to your own experience just to explain it to an inquisitor? My eyes glaze over just thinking about it!

There is a better way. All of these diets have a clear, underlying purpose: to control insulin. Why not just call it Insulin control?

By starting with this core tenet, I can transcend the diet denominational mess.

Insulin control gets to the heart of the matter, which is that excess or chronic insulin in the blood leads to fat storage, loss of insulin sensitivity / increased insulin resistance, downregulation of fat mobilizing hormones (adrenaline, noradrenaline, glucagon and human growth hormone), and can ultimately lead to symptoms of metabolic syndrome, including hypertension, obesity, cardiovascular disease, diabetes and cancer. How do you control insulin? Insulin control can be accomplished via reduction in carbohydrate intake or via controlling feeding times (via fasting) so that insulin levels sufficiently drop, which allows fat mobilization to resume.

Calling what we do “insulin control” focuses on the problem and implies the solution. It also grounds the diet/lifestyle to its fundamental science while avoiding the pitfalls of bias-loaded words. Starting an argument from “insulin control” gets me to low-carb, to fasting, to evolution, to metabolic syndrome, to higher-fat consumption, to more natural/less process foods. Why bother with the varying brands when it’s all about insulin control!

Further reading:

  • Go here to get started on some fantastic quotes on insulin, sugar, glucose, etc. If you’re not already practicing a low-carbohydrate lifestyle, read up.
  • Art De Vany wrote a reasoned response to the contention that the Paleo / “EF Way of eating” (See how muddled that is!?) was a fad diet. His most excellent point was that the current American diet is much more a fad having been around for merely decades relative to the stacked millennia of two million years (Tyranny of Present fallacy).
  • In mentioning Johnson’s UpDayDownDay diet, Patri Friedman notes how excellent it is that such a variation of research is occurring surrounding caloric restriction. What I wonder: is caloric restriction / fasting an emerging diet trend? I plan on doing a tiny blog on this later. Stay tuned.
  • While I was writing this entry, the IF life published a diagram that lays out how to stay on track for weight loss. It’s a useful, informative and simple diagram. And what will you note in the middlemost bubble? Control insulin!
PermalinkPermalink Friday June 13 at 09:13:15 pm, by Justin — 1 comment »

Improve your Health via Hormesis - Stress Out.

As alluded to previously, injecting small doses of stress into an otherwise harmonious existence can improve your health. This phenomenon is called hormesis. Here’s a googled definition of hormesis:

A dose response phenomenon whereby a substance that in a high dose inhibits (or is toxic to) a biological process, in a much smaller dose will stimulate (or protect) that same process.

Toxic substances stress us. Stephan explained it nicely over at Whole Health Source:

Hormesis … increases resistance to other, more intense or chronic stressors. It can increase resistance to a variety of stresses, not only the one to which you are exposed.

Hormesis is a powerful, non-obvious-yet-evolutionarily-intuitive idea — I can improve my health by intentionally introducing some stress into my otherwise pampered, stress-free life. And here are a few applications:

  • High-intensity exercise. I lump in here anything that briefly elevates my heart-rate and requires my body to do a significant amount of work. Weight-lifting, sprinting and kettlebell drills readily come to mind.
  • Fasting / Intermittent Fasting. Going without food is quite possibly the easiest path to the benefits of hormesis. Shameless self-promotion: on fasting (application and benefits) and more recently on caloric restriction / resveratrol and the potential for slowing aging.
  • Drinking alcohol. We’ve heard this before — drinking one to two alcoholic beverages a day may benefit cardiovascular health. It seems that the benefit of drinking alcohol is from its hormetic effect.
  • Smoking tobacco. First, I gleaned this application from Arthur De Vany. Dr. DeVany applies it via cigars. I see no reason it could not also be applied via a pipe or some type of snuff or chew. I personally enjoy the occassional cigar or alternatively, will smoke a pipe. One thing to note: inhaling might eliminate the hormetic benefit of tobacco use by taking it from a mild dose to a heavy dose. I simply don’t know.
  • Cold showers. I snagged this one from Richard Nikoley. I then reread the idea from Art and then Stephan, who says it helps fire up “non-shivering thermogenesis”. If you want to read more about activating cold via hormesis, check out what a DeVany reader sent in on the subject of brief exposure to cold.
  • Radiation. I mention this only for completeness, but small exposure to radiation is a tactic to increase resistance to larger doses of radiation later (Surprise, its controversial). I don’t know of any way for normal folks to apply radiation hormesis.

The above are fairly non-controversial ways to practice “stressing out", and thereby benefit from hormesis (Excepting radiation hormesis). However, I wonder if there are other things one could do. Here are some alternative hormetic possibilities:

  • Get less sleep. Maybe periodically cut back on your sleep by 30%. I’ve occasionally experienced increased alertness on less sleep. However, the positive effect wears off in time. Prolonged lack of sleep also weakens your immune system, which doesn’t sound too beneficial.
  • Binge on fruit. Assuming you are a low-carber, eating a lot of fruit at one time should result in a sizeable insulin response. If you aren’t on a low-carbohydrate diet, binging on fruit won’t do much to acutely stress your body.
  • Get some sun. Beneficial for Vitamin D purposes, seems like this would also make sense for potential hormetic effects.
  • Expose your kids to allergens. Didn’t know for sure where to put this one and I don’t have kids. However, I’ve read that exposing your kids to cats may reduce the risk of allergies and asthma. Is the benefit here hormesis? Also, is there a risk in overprotecting your kids from germs?

If you have any other ideas for unconventional applications of hormesis, I would love to hear them.

Finally, let’s remember that high doses of toxic substances can impair your health or even kill you. High doses of stress are likewise unhealthy. Therefore, may I present one last list of bad ways to stress out:

  • Over-training (And also, potentially, endurance exercise). Not allowing your body to recover from exercise is a recipe for disaster. Endurance activities like running marathons (or jogging long-distances) might also be harmful (Art De Vany thinks so). I speculate that endurance activities may be safe so long as they are using fat oxidation for energy (See endurance athlete Mark Twight’s write-up on fat). This would necessarily require a lower intensity for most all of us who don’t train to exercise for hours on end — an effort probably no more intense than walking or leisurely riding a bike.
  • Stressing about work, money, family, relationships, career, or the meaning of life. We’ve all done this. However, can you imagine our evolutionary ancestors experiencing existential angst? I can’t. Food availability, yes. Finding shelter, sure. Avoiding predators, certainly. I’m no expert on meditation or any other specific methods for stress reduction. When I get stressed out about life for too long, I just try and step back and see the big picture and/or let go. It helps.
  • Cut back on the caffeine. This is a tough one for me. I drink a good bit of coffee on a daily basis. Caffeine might have hormetic benefits — but I doubt they occur if you’re a chronic user like me.

Anything I missed? If so, please let me know.

Parting thoughts: introduce some “stress” to your life and improve your health. A cold shower followed-up by a 24-hour fast is an easy way to get started. Finish off the fast with some hill sprints. Practice hormesis. If you can consciously control the stressors in your life, you just might live longer.

PermalinkPermalink Wednesday June 11 at 01:45:30 am, by Justin — 1 comment »

Caloric Restriction, Red Wine, and Aging

First, a summary:

  • The physiological stress resulting from caloric restriction may extend your life. It could accomplish this by switching resources from reproduction to self-preservation. Alternatively (or additionally), it might accomplish this by helping downregulate insulin, thereby reducing the diseases associated with metabolic syndrome.
  • Resveratrol (Via red wine, for now) might also slow aging via some SIRT-1 mechanism or by somehow signaling to the body that stressful times lay ahead.
  • The stress from exercise3 might slow aging by activating physiological mechanisms of tissue self-preservation, as well.
  • And finally, I can chalk another one up for intermittent fasting, which personal experience says is the easiest way to practice caloric restriction.

The Details

My brother sent me a NYTimes article that talks about resveratrol, a molecule found in red wine, and its possible link to slowing aging. Resveratrol may thwart aging by spurring the production of sirtuins a.k.a. SIRT1 in humans. Per the Times:

[T]he door has now been opened to drugs that exploit an ancient biological survival mechanism, that of switching the body’s resources from fertility to tissue maintenance. The improved tissue maintenance seems to extend life by cutting down on the degenerative diseases of aging.

The reflex can be prompted by a faminelike diet, known as caloric restriction, which extends the life of laboratory rodents by up to 30 percent but is far too hard for most people to keep to and in any case has not been proven to work in humans [See Footnote 1 for discussion on this last sentence].

Whereas the Times article focuses on resveratrol, summarily dismissing caloric restriction, a 2006 article from The Economist does the opposite, going into more detail on the impact of caloric restriction on human aging and a recent study on the matter:

[E]vidence has been accumulating since the 1930s that calorie restriction … extends lifespan and delays the onset of age-related diseases in rats, dogs, fish and monkeys. …

Amid the hype, it is easy to forget that no one has until now shown that calorie restriction works in humans. That omission, however, changed this month, with the publication of the initial results of the first systematic investigation into the matter. This study, known as CALERIE2 (Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy), was sponsored by America’s National Institutes of Health. …

CALERIE suggests the [advantages of caloric restriction] are real. For example, those on restricted diets had lower insulin resistance … and lower levels of low-density lipoprotein [LDL] cholesterol. They showed drops in body temperature and blood-insulin levels?both phenomena that have been seen in long-lived, calorie-restricted animals. They also suffered less oxidative damage to their DNA.

The Economist article goes on to talk about resveratrol and even exercise:

Resveratrol is produced when a vine is under stress?for example, due to dehydration or over-exposure to sunshine. According to Dr Sinclair’s theory, which he calls xenohormesis, animals rely on such botanical stress signals to give them extra information about their own environments, in the same way that the alarm calls of one species warn others of danger. If bad things are happening to plants, he surmises, that is a reason for pre-emptive animal action. Animal bodies thus react to molecules such as resveratrol by activating their own defence mechanisms. These, in turn, protect their cells from stress-related damage.

Xenohormesis is a variation of a more general theory, hormesis … A good example of hormesis is exercise. In theory, this should damage cells because it increases oxygen uptake, and oxidative stress is bad for things like DNA. Of course, exercise is not actually bad for cells?and the reason is that the body activates defence mechanisms which overcompensate for the stress the exercise creates, producing beneficial effects. So, while chronic stress is always bad for you[3], a short period of mild stress followed by a period of recovery can be good.

More on hormesis here.

So what’s the common denominator between exercise, resveratrol, and caloric restriction? Stress. The introduction of acute stress may switch the body’s resources from reproduction to self-preservation4. From an evolutionary perspective, this makes sense. If a band of human beings were facing environmental hardship, such as a famine, their bodies would need to self-preserve until times more suitable for the ultimate biological imperative, reproduction.

Beyond acute stress causing self-preservation and thereby slowing aging, there may be another angle here: insulin. Caloric restriction will reduce insulin loads on the body as entering a fasted state will require the body to switch from glucose-burning (Insulin upregulated) to fat-burning (Insulin downregulated). As I’ve blogged before, chronically high insulin (via diets high in carbohydrates) in the blood is positively correlated to metabolic syndrome or Syndrome X. The connection to slowed aging and lower insulin levels could just be the other side of the same coin, but if nothing else, it’s more support for incorporating some amount of caloric restriction in your life.

Footnotes:

1 I’ve got a question out to the author, Nicholas Wade, as to his last claim regarding caloric restriction and its impact (or lack thereof) on humans. I’m fairly certain that Wade means that the life-extending impact of caloric restriction has yet to be proven for humans, even though the CALERIE study mentioned above would contradict such a claim.

I take serious issue with Wade’s ambiguity here. Most of his article is about resveratrol and sirtuins and their potential link to slowing aging in humans. He goes into detail about a pharmaceutical company that is working on producing a drug that might induce the same effects. That’s fine, but why slam the door on an alternative (caloric restriction) that might slow aging for free? Is it because it’s “far too hard for most people"? How did he determine that?

Update 2008-06-13: Received a response to my email to Nicholas Wade. From part of my email:

Or do you mean that sufficient testing on caloric restriction’s impact on human aging has not occurred, thereby the theory remains unproven?

He indicated that the above interpretation was the one he intended. I will let him know about the CALERIE study.

2 Here is the official CALERIE website.

3 Perhaps therein lies some support for the claim that endurance training is unhealthy as it puts a chronic load of stress on the body.

4 Not surprisingly, Art De Vany mentions as much in passing here:

I practice intermittent caloric deprivation. This is a known enhancer of the immune system. This is pure evolutionary reasoning. During deprivation, the system reallocates resources from reproduction to repair and maintenance. The immune system is part of that adaptation.

PermalinkPermalink Thursday June 05 at 06:35:00 pm, by Justin — Leave a comment »

Better Health via Intermittent Fasting and a Low-Carb Diet

I’ve been on a low-carb diet now for about two-and-a-half months. This has consisted of eliminating all breads, potatoes, and starchy foods from my diet (Regarding fruit, I pass on bananas with only the occasional apple while still eating berries and other colorful fruits). Furthermore, it has involved intermittent fasting. Through this diet and with minimal exercise, I have reduced my body fat percentage from around 20% to around 10% representing a loss of some 15+ lbs of fat and the gain of a handful of pounds of lean tissue (Weight change from approx. 182 to 168).

This weight loss was the easiest, most satisfying change in my health and body composition I’ve ever experienced.

As this post is extensive, here is the general breakdown:

  • Intro and Intermittent Fasting
  • Low-carb diet
  • Implementation and Conclusion
  • Additional Reading
  • Footnotes

Here are the details:

Intermittent Fasting

Yes, you read correctly, I used the “f word": fasting. And I can read your mind:

  • What? You starved yourself?
  • Is that for religious reasons?
  • Yeah, that’s called anorexia!

No, no and no. And if I missed any others, no to them, too.

I first got turned onto Intermittent Fasting (IF) via Richard Nikoley over at Free the Animal who had been practicing Art Devaney’s evofitness sans fasting for about a year. Upon trying IF, Richard immediately noticed results in the form of both significant weight loss as well as change in appetite.

Richard’s successes seemed interesting enough from a distance (Fasting? Fascinating but not for me!), but what catalyzed a personal trial in IF and low-carb came after watching a lecture1 by science writer Gary Taubes, author of Good Calories, Bad Calories ("GCBC").

The big takeaway from the referenced lecture was that insulin, not overeating or under-exercising, is the chief culprit in why people become fat. Since eating carbohydrates causes the pancreas to secrete insulin, there is a direct correlation between carbohydrate consumption and insulin secretion. Ipso facto, the argument is made that eating carbs makes you fatGCBC.

Could it really be that simple? Dieting and working out had failed to reduce my weight effectively — it certainly seemed like something else was affecting my weight. Richard’s success and Taubes’ conclusion sufficiently piqued my interest. Admittedly without knowing all the data, I chose to do an IF, low-carb experiement.

What exactly is intermittent fasting? Intermittent fasting is choosing not to eat for a set period of time, which unlike your daily sleeping fast, is a sustained break from regularly occurring feeding. Translated into some bright line rules, I’d define an intermittent fast as going at least sixteen hours without eating (call that a “short” fast) or going for as long as 30 - 36 hours or three meals ("long fast"). As defined here, a fast requires there be no dietary caloric load on your body.

Fasting for longer than 36 hours likely will not only result in diminishing marginal returns, but it could also start messing with your metabolism. Most obviously, all fasts must be broken by eating.

Completing one to two long fasts per week so long as they are separated by eating a few meals can result in some drastic health benefits while causing no harmful effects on metabolism so long as you are completing some form of regular high-intensity exercise2.

What happens when you fast? Some interesting biological things, apparently. For one, the body moves to mobilize fat stores from the adipose tissue (the fat under your skin) to consume the fat as energy. It accomplishes this fat mobilization as a natural extension of reducing insulin concentrations in the blood as well as an increase in fat mobilizing hormones such as adrenaline, noradrenaline and growth hormone. Interestingly enough, growth hormone is also released to conserve protein from catabolism. Protecting the proteins in your body during a fast is important because your body needs its lean tissues to survive (be they muscle or organ).

A benefit of fasting (for your mind) is that it alters your perspective on eating. At the end of a 30 hour fast, you want to eat something good for your body. You don’t want to gnosh on some french fries, slam a sugary soft drink and eat a bowl of ice cream. Even more, via abstaining from food even when it is available for consumption, you are putting your mind in control of your behavior. Taking back a bit of control over your life is an empowering feeling that leads to improved self-image and confidence.

Biologically, whether fasted or fed, your body is going to take measures to maintain adequate energy flows to demanding muscles and organs. Your body gets this energy from dietary sources or from storage within the body. The key here is that your body is always working to strike an appropriate balance (homeostasis) given the current demands. Were it not managing this process, both eating too much or eating too little would result in your untimely demise!

The ability of our bodies to regulate energy during times of feast or famine is evolutionary engineering. It is reasonable to posit that homo sapiens have only recently lived in such abundance that they could expect to eat food throughout the day, three times a day or more. Go back 50,000 years and you’ve still got mostly the same genetic footprint for human beings, but an entirely different supply of food. These were times when “foraging for food” meant more than a run to the pantry. In other words, our genetics have been engineered to allow us to go without food for longer than ten hours without resulting in our bodies failing. For a tidbit more on the evolutionary aspects of intermittent fasting, see footnote 7.

The bottom line: by reducing insulin in the body and up-regulating fat mobilizing and protein-protecting hormones, IF naturally turns your body into a fat burning machine. During a fast, your body will use whatever energy necessary, which will be similar to the amount of energy required were you eating normally. Over a long fast, if your body requires 2,500 calories, you could expect the majority of that energy to come from fat stores. Thus, the combination of IF with exericse is an effective way to reduce fat stores and work towards a leaner body composition.

Now, the astute reader asks, “Couldn’t you switch your body to being a fat burning machine by cutting out carbohydrates from your diet? If you only ate fat and protein, your body would have to burn the fat for energy, right?”

Good question!

Low-carbohydrate diet

And the answer is, of course, yes! The metabolic pathways while on a fast are the same processes when on a low-carbohydrate dietGCBC (Also see Eades here). This is because in both states (fat/protein-fed or fasted) your body is going to rely on free fatty acids as its main source of energy. Does it really matter that the fat comes from dietary sources or from your cells? Apparently, not3.

If you want to know a ton more about this, and I reiterate this in the footnotes, pick up Gary Taubes’ Good Calories, Bad Calories, an exhaustive book about the science and history of the low-fat-is-healthy hypothesis, the varying research studies behind low-fat diets, the research behind low-carbohydrate diets, obesity, diabetes, insulin, caloric restriction, exercising to lose weight, metabolic syndrome, some biochemistry and more. GCBC is a fascinating and eye-opening read.

As noted before, Taubes concludes that insulin is uniquely fattening. And again, since insulin is released after eating carbohydrates, carbohydrates are fattening.

Insulin is a hormone produced by your pancreas that regulates blood sugar, or glucose. Glucose comes from carbohydrates either directly or upon digestion. The presence of insulin downregulates fat mobilizing hormones (Human growth hormone, adrenaline, noradrenaline, glucagon, for example). Upon the introduction of insulin into the bloodstream, free fatty acids are driven back into fat cells for storage as they are now deemed unnecessary given the newfound energy. When all this energy leaves your bloodstream, you get hungry! In this manner, consuming carbohydrates not only shuts down fat mobilization but it can even spur hunger.

Furthermore, insulin tells your liver to take glucose and make triglycerides or fat for storage. Even more, if you note the “glyc” in triglycerides — that is for glycerol phosphate which holds the long fat chains together. Guess where your body gets glycerol phosphate? From metabolizing glucose! Thus, not only does the presence of insulin spur hunger and fat manufacturing by the liver, but the glucose facilitates fat creation by providing the molecule necessary to build the fat!

Insulin, by way of carbohydrates, is like the triple threat to being lean. It follows logically that by reducing insulin concentrations in the body, you can curb hunger, stop fat storage, and maintain the fast-induced fat mobilization process discussed earlier.

You reduce insulin concentration by fasting and avoiding carbohydrate-dense foods.

Though it is unnecessary to fast while on a low-carb / carbohydrate restricted diet, fasting speeds things along via caloric restriction overall while still allowing you to eat normal meals when you do eat. Taubes contends that a fast effectively accomplishes the same thing as Atkins’ induction phase, which is a two-week period of eating twenty grams of net carbohydrates a day or less4.

Implementation:

Though this is by no means the way to implement this diet, this is my semi-specific methodology. You must pay attention to your own results and customize a system that works for you.

Fasting: On a day when I plan to start a fast, I eat breakfast and lunch. Then I eat nothing else until dinner the next day. During the fast, I am free to drink water, tea and coffee so long as no creams or sugars are added. Some even say diet soft-drinks are ok but I universally avoid artificial sweeteners. All said, this results in anywhere from a 26 - 30 hour fast.

I make it a point to do about twenty to thirty minutes of high-intensity exercise about an hour or two prior to breaking my fast (typically some combination of multi-joint weight-lifting like dips, pull-ups, squats, kettlebell exercises, etc.). Whether you do your high-intensity exercise while in a fasted state or not, the exercise must be done! It is not optional.

I break the fast with a nutritious meal with normal-sized portions. In all meals, I avoid or eliminate carb-heavy foods. I avoid bananas and apples and all juices while regularly eating all types of berries, tomatoes and avocados. Nuts are okay though peanuts are not nuts but legumes (I still eat them from time to time though).

As far as portion size, Art DeVany says, and I think this is sound advice, to eat to satisfaction not to fullness.

Breads, potatoes, legumes and candy are off limits. Yes I cheat from time to time. I accept it and don’t allow it to overthrow my broad efforts. I find myself cheating less more and more as my body further detoxifies from the high-glucose, high-insulin addiction. I do not avoid beer or wine though I am always sure to stay hydrated and again, pay attention to your bodies!

For breakfast, I regularly eat a couple eggs (yolk never excluded), bacon or sausage (uncured) and berries. Some say avoid dairy, I do not and have not, regularly consuming cheeses and heavy cream. I do avoid milk and yogurt (can’t find any yogurt without a minimum of 15 gm of sugar). Remember: fat is ok. For me, low-carb did not mean “high protein” — it meant “high fat". We’ve all been programmed to be scared of “high fat” — if you need some guidance in getting over your fear of fats, pick up Taubes’ book.

After breaking a fast, eat at least six meals before doing another fast.

Some notes:

While on any initial fasts, be prepared for some folks to think you are completely insane. If you keep it up, you’ll laugh when you find some of these people trying it out themselves a month later. Also, some people may experience headaches while fasting (particularly women). This is your body struggling with the swithover to fat as energy. Feel free to start with smaller fasts (say sixteen hours) before working up to a longer fast. Again, this is very personal — the nuances of insulin-sensitivity differ from person to person. Do what works for you.

If you try this out, please report any results. Questions? Comment below or email me.

Finally, a disclaimer. I am not a doctor. All of the above is for information purposes only. Any experiments you try on yourself are your own responsibility!

Conclusion:

I feel good practicing IF and a low-carbohydrate diet. The cravings for things like pizza go away faster than you might think. Excluding easy, filler-type foods makes you a smarter, more creative chef.

Via this regime, nay lifestyle, I’ve gotten back down to a body composition level akin to when I was eighteen, something I had long given up as impossible5. And I’ve done it in only a matter of a couple months.

My results being undeniable, I now have my father-in-law, wife, and brother all practicing this diet, something I now see as a way of life6 that I can maintain indefinitely. My sister-in-law and sister are also dabbling with the diet, too.

Additional Reading:

  • Fat: Mark Twight of Gym Jones talks about how endurance athletes run more efficiently on fat than on carbohydrates.
  • Martin Berkhan of Leangains talks about his history starting with when he was clearly overweight, to uber-skinny model, to experimenting with IF and weight lifting. Also read an interview with Martin here.
  • Fast 5 — a free ebook about fasting on a daily basis, not unlike Martin’s regiment in fast duration. A good introduction to IF.
  • Artificial Sweeteners Cause Energy Disregulation: More compelling (to me) than the arguments that artificial sweeteners cause cancer, is the contention that zero calorie sweeteners confuse our bodies, causing disregulation. I’ve avoided artificial sweeteners for the past two and a half months and haven’t missed them a bit. Note: had to link only to the clip I saved as Art has moved that post offline (or out of public view).
  • Big Fat Lie: an article from the UK Telegraph on Taubes. Read it and get the book if your interest is still piqued.
  • Intermittent Fasting: Art Devany is an expert of sorts on the paleo diet (which is low-carb by nature) and evofitness, which is high intensity “power law” training. Here he talks about his approach to IF, which of course, would have fit perfectly with the paleo lifestyle. Art is 70 and looks fantastic. Read his post on mental clarity and fasting. Note: both of these links are dead as Art redesigned his site and took much of the original content offline (unfortunately).
  • Your belly fat could be making you hungrier: A quote from the research:

    The extra fat we carry around our middle could be making us hungrier, so we eat more, which in turn leads to even more belly fat. Dr. Kaiping Yang and his colleagues at the Lawson Health Research Institute affiliated with The University of Western Ontario found abdominal fat tissue can produce a hormone that stimulates fat cell production. The researchers hope this discovery will change in the way we think about and treat abdominal obesity.

    More from Devany here. Basically, the fat in your abdomen is the last to go — almost fighting for its own existence towards the bitter end!

  • A Motivation I Haven’t Written About: Richard Nikoley talks about the link between carbohydrates and cancer cells. Apparently, cancer cells have an incredibly difficult time running on anything but glucose and even then, they burn glucose quite inefficiently. For this reason, a low-carb diet may have benefits for people fighting cancer.

There are others which I’ll have to point to in the future.

Footnotes:

GCBC Despite the name indicating the book is about foods and calories (a diet book), Good Calories, Bad Calories is a fantastic read on the history of research on low-fat and low-carb diets, insulin, weight-loss, pre-Westernized cultures and nutrition, cholesterol, cardiovascular disease, cancer (metabolic syndrome or “diseases of civilization") and more. If you want to learn all about these topics, you must pick this book up. If you are skeptical about low-carb diets, I implore you to read GCBC. It is a fascinating read at approximately 450 pages (Note: the book is 600 pages, but 150 of them are references!).

1 Watch Taubes lecture on “Big Fat Lies” on Google video here

2 Defined as low quantity or time, high quality or work completed. Volumes could be written (and have been) on this subject. Bodyweight circuits where exercises are performed back to back (See C8B300 for an example) are one form of this. Tabata intervals are another. A Body For Life style cardio session is also popular where you do 2 minutes at Level 5 intensity, then four sessions of one minute each at levels 6, 7, 8, 9 and end with a minute at level 10 and then a minute of cooldown back at level 6 (This adds up to 20 minutes total: 2 warmup, 16 on the four minute intensity cycle, one at peak intensity, and one at cooldown).

3 Therein possibly also lies the answer to a question that arises regarding low-carb diets compared to non-low-carb caloric restriction diets. Research has shown that low-carb dieters can severely restrict calories, achieve significant weight loss, and not be hungry. Comparatively, non-low-carb calorically restricted diets wreak havoc on the dieters making them cranky and typically resulting in all the weight going back on upon ceasing the diet.

4 Many, many people I’ve talked to about this think I’m doing the Atkins diet. If I am, fine. Honestly, I haven’t read Atkins stuff well enough to say if I’m following his protocol or not. I mention the comparison of a fast and the induction phase as a means to point out the connection between fasting and low-carb diets as well as the benefit that fasting provides in terms of speeding along the process.

5 Having tried the aforeblogged Getting back to fighting weight (Post deprecated) Body for Life program and seen results, but only after untold hours in the gym (probably on the order of 100 hours) and pounding three protein shakes per day in addition to three meals.

6 Fasting twice per week is not something you have to do indefinitely. In fact, its too regular to maintain on a permanent basis. Our bodies should be kept on their toes! Periodically going to only fasting once a month would be an option (Or once every other week). Just be sure to mix it up. My guess is that once you try fasting, you’ll find that going on a periodic fast is something you want to do to clear your mind, body, etc. and/or ward off a cold, get over a weekend of gorging, whatever.

7 This diet conforms readily to the way our bodies seem to be genetically engineered by tens of thousands of years of evolution. Hunter/gatherer man wasn’t looking for french fries and rolls! It has only been in the past ten millennia that carbohydrate-dense, processed foods have been available for consumption. Our bodies simply struggle to cope with such a drastic shift in diet from nuts, berries, leafy greens (all slow-to-metabolize carbohydrates on the glycemic index), and meat to breads, rices, potatoes, and sugar which require immense amounts of insulin to regulate.

PermalinkPermalink Friday May 16 at 12:36:41 pm, by Justin — 7 comments »

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