Tweaking & optimizing

Posted on Fri, 11 August 2006 by Mel Green

I was attracted to Precision Nutrition by John Berardi’s discussion at his website of insulin resistance & insulin sensitivity. In my own research on insulin resistance, prediabetes, & Type 2 diabetes, I learned a few months back about how fat loss (not just “weight loss”), muscle-building, & healthy diet are important to increasing insulin sensitivity. In consequence, I overhauled my diet & got off my sedentary butt to get more exercise: dancing, weights, walking, biking. I’ve lost 18 pounds this way since late December, but probably even more in fat, as I have also become somewhat more compact & muscular. All of this can be read about in this blog.

But I’ve still got some ways to go.

Thus, on a search to improve my exercise program, I was glad to get an email from Tom Venuto (whose Burn the Fat, Feed the Muscle has been an important guide for me) pointing me in the direction of Craig Ballantyne’s Turbulence Training program. Ballantyne’s TT blog in turn referred me to John Berardi’s website, & thus to Precision Nutrition: which seems the ideal program for tweaking & optimizing my diet for increased & healthy fat loss & insulin sensitivity.

So I’m entering another stage of my progress toward insulin sensitivity & restored health. My plan from here on out, once we settle down from the Moving Hell we’ve been in (moving from one apartment to another), I will:

  1. Join the gym a few blocks away
  2. Commence the Turbulence Training program
  3. Commence tweaking & optimizing my nutrition with the Precision Nutrition program

This blog has been scant on direct feedback measurements except for daily counts of steps (or their equivalent) in the workplace “Start Walking” program I’ve been engaged in. As I begin to implement the TT & PN programs, I plan to include more detail about what I’m eating & what my workouts are like, as well as feedback stats such as body fat percentage, scale weight, & — since I’m insulin resistant & prediabetic — blood glucose measurements. (I’d measure blood insulin too, but unfortunately there are no simple fingerprick tests for that!)

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A little experiment in interval training

Posted on Wed, 9 August 2006 by Mel Green

Over the past couple of weeks I’ve been in the midst of moving hell, which has caused my regular exercise to suffer somewhat. Though not as badly as I’d feared — it’s amazing how much walking one does just carrying boxes from one apartment to the car, & from the car into the other apartment. And if lifting all those boxes full of books (we have lots of them) isn’t resistance training, I don’t know what is. And so I still went down a couple of pounds over that time.

But now I seem to be seeing results from an experiment that I tried Monday & tried again yesterday. My experiment involved what’s called interval training, which (as I wrote three weeks ago) is a way of doing cardio (aerobic) exercise in which you alternate a brief period of really fast, intense exercise with a “recovery” period of doing the same exercise at a slower rate. For example, after first warming up: run as fast & hard as you can (on the street or a treadmill) for 30 seconds so that your heart rate is up really fast, then slow down to a more moderate running pace for a minute or two… & repeat this three or four times. I got interested in interval training because from Craig Ballantyne as well as other sources I’ve heard a lot about it being probably better for burning off fat than moderate-level aerobic exercise for the same or even longer duration.

My experiment was with walking. Monday morning I got off at an early bus stop, which I often do to get more exercise. The walk from that bus stop to my workplace takes about 20 minutes. During the walk, three times I really intensified how fast I was walking for about a minute each time. I was wearing a heart rate monitor, & was able to get my heart rate up to about 80 percent of my maximum heart rate capacity. When I slowed down during the “recovery” periods, I was still at about 65 percent of maximum.

I tried it again yesterday on my way home — again, getting off at an early bus stop. Wasn’t wearing a heart rate monitor this time, but I could feel my legs burn during the one-minute fast walking periods. Again, three fast times at one minute each, slowing down in between.

This morning my scale said I was about 1.5 pounds less. It seems to be verified by the better scale at work too. Not ready to claim that loss quite yet… but it certainly gave me pause.

No, not pause: rather, desire to keep it up. Now that we’ve got the worst of the move over, I will be joining a gym where there are stationary bikes & other things I can use to help me with the interval workouts. (Not to mention resistance training.)

One more tool toward fat loss & increased insulin sensitivity.

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Anabolism, catabolism, & insulin: The definitions I go by

Posted on Wed, 9 August 2006 by Mel Green

I just want to provide some basic definitions to illustrate the terms that I’m using & how I understand them, & to try to state my basic understandings as clearly as I know how to.

Anabolism: The phase of metabolism in which simple substances are synthesized into the complex materials of living tissue.

Catabolism: The metabolic breakdown of complex molecules into simpler ones, often resulting in a release of energy.

Both of my sources for these definitions (through the clickable links) are worth looking at, because they include dictionary definitions from several sources, as well as Wikipedia articles which explain in more depth.

Basically, anabolism means taking simpler stuff & using it to build more complex stuff within the body: amino acids into protein into muscle, blood glucose into adipose tissue (body fat), etc. Catabolism does the opposite: it breaks larger, more complex molecules into simpler stuff, usually with a release of energy, for example, burning off fat through exercise or going on a low-calorie starvation diet that leads to the loss of lean muscle mass.

Insulin is anabolic in these ways:

  1. Insulin tranfers blood glucose to the liver & to muscle cells to either be burned for energy, or to be synthesized (that is, built into) glycogen. Glycogen is “animal carbohydrate” which can be burnt (catabolized) when quick energy is needed for exercise or an emergency. Insulin is anabolic because it helps build glycogen.

    [Edit: I misstated that. Actually, glycogen itself isn’t burnt for energy. Rather, it’s converted back into glucose (a conversion stimulated by the catabolic hormone glucagon) & the resulting glucose can then be burnt for energy.]

  2. Insulin transfers excess blood glucose, that is more than the body needs for its immediate energy requirements or for replenishment of its glycogen stores, to fat cells for storage as adipose (fat) tissue. Insulin is anabolic because it helps build body fat.
  3. Insulin transfers amino acids in the blood for uptake by the muscle cells to be synthesized into proteins for muscle growth. Insulin is anabolic because it helps build muscle.

(See more about insulin from Answers.com.)

There are other hormones which are catabolic, such as cortisol & glucagon, which specialize in breaking down muscle proteins, glycogen, etc. Cortisol, for example, is a stress hormone that (amongst other things) breaks down muscle proteins, which will lead to an increase of glucose in the blood. Insulin then goes to work to take care of the glucose, & if (as in point 2 above) that’s more glucose than you need for energy or glycogen replenishment, insulin will exercise its anabolic function with respect to body fat by dumping that insulin into your fat muscles.

In a healthy person, all these hormones & more act in balance with each other to keep you healthy. But if something is thrown out of whack, your hormones will still keep doing the jobs they were made to do even if doing their jobs might mess you up even further.

That’s what happens with insulin resistance. It’s not insulin itself that is the problem, but the insulin resistance that comes from eating too many carbohydrates, especially highly refined carbs that are digested quickly. By eating too many carbs, you put your body into a chronic state of too high blood sugar. High blood glucose leads to high insulin levels, because the insulin is trying to take care of all that sugar. You become insulin resistant, high insulin levels in your blood becomes chronic, all that excess blood sugar gets dumped as fat, & as you get fatter you also get more & more unhealthy & begin the progression to diabetes, cancer, heart disease, etc. Not only are the natural, healthy functions of insulin thrown off, but so are the functions of the other hormones & systems in the body.

Unless you do something to change your situation.

Let me put it very clearly: my view is that insulin resistance & chronic high insulin levels are very bad things. That’s why I have been working my butt off to increase my insulin sensitivity.

A healthy body is insulin sensitive, & so needs relatively little insulin to take care of the jobs that insulin was made to do, including shuttling blood glucose & amino acids to the places where they’re needed to keep on building & maintaining a healthy body. That includes shuttling amino acids to where they’re needed — in the muscles — & participating in the anabolic process of muscle-building.

In the body that is unhealthy because of insulin resistance, more & more insulin is required to do the job, not because insulin isn’t doing its job, but almost always because the body’s owner is making its job very hard for it by eating too much lousy food, not getting enough sleep, not getting enough exercise, & making other bad lifestyle choices. Probably insulin & the other hormones are all having problems doing their job exactly right because of the challenges the bad lifestyle choices are putting to them. Your entire metabolic system goes out of whack, out of balance.

Finally, about insulin’s anabolic role in building muscle: I learned of this just last week at John Berardi’s website, & have researched it quite a bit since, & based on scientific articles, medical dictionary definitions, & some of the sources I’ve cited in this message I believe that Berardi is right. But Berardi does not say, nor do I, that high insulin levels are a good way to take advantage of this fact. His approach (as mine) is not to increase insulin levels, but on the contrary: to increase insulin sensitivity so that less insulin is necessary to do the job & do it right.

I learned doing research that there are a lot of bodybuilders who actually take insulin shots in order to take advantage of insulin’s anabolic properties re: muscle. This is a stupid & dangerous thing to do. Because of course insulin is also anabolic with respect to body fat, not to mention that high insulin levels leads to insulin resistance. So these abusers of insulin are actually making themselves less healthy. Needless to say, Berardi recommends against this idiotic kind of supplementation.

These are the definitions I’m using, & the understandings I have at the present moment, which are subject to modification as I increase my understanding.

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Water is wet, & insulin is anabolic

Posted on Wed, 9 August 2006 by Mel Green

So who cares?

Apparently at least one person, who continues to find what I’ve learned about the anabolic role of insulin with respect to muscle to be downright objectionable.

And thus I came back to my computer after the weekend to find a couple more posts registering this person’s objections, not to mention her mischaracterizations of John Berardi & of what I wrote about his approach.

A definition of insulin from The American Heritage® Stedman’s Medical Dictionary, 2nd Edition (2004):

insulin: 1. A polypeptide hormone that is secreted by the islets of Langerhans, helps regulate the metabolism of carbohydrates and fats, especially the conversion of glucose to glycogen, and promotes protein synthesis and the formation and storage of neutral lipids.

Promoting protein synthesis is anabolic. So is “the formation and storage of neutral lipids.”

The same dictionary gives the definition of catabolism as follows:

catabolism: the metabolic breakdown of complex molecules into simpler ones, often resulting in a release of energy.

But it’s not good or healthy to have too much insulin in your blood. No indeed, nor did I ever suggest that it was. Too much insulin leads to insulin resistance & promotes obesity, because of course insulin is anabolic with respect to adipose tissue (body fat) too.

But I was surprised when insulin’s anabolic properties became such a bone of contention on the Insulin Resistance list: when I first mentioned insulin as anabolic for protein (muscle) as well as fat, I thought I was just discussing a fact well known to science & medicine that I hadn’t known before. Having someone insist that, no — contrary to what is said by science or medicine or numerous research reports in medical journals available for anyone’s persusal at PubMed — insulin is “catabolic,” has been rather like to having someone insist that no, water is in fact not wet.

The source that I happened to learn from about insulin as a muscle-promoting hormone happened to be that of someone who specializes particularly in nutrition for athletes — John Berardi, Ph.D. in exercise biology & nutrient biochemistry. His credentials can be read here. He’s far from ignorant when it comes to matters of nutrition; on the contrary, he consults to or actually designs nutritional programs for numerous athletic teams & individual athletes (as well as lots of sedentary individuals) because what he says works.

I’m not an athlete, just a 47-year-old insulin resistant woman who’s been working her butt off to throw off my sedentary ways & become fit & healthy. But his approach has some lessons for me. Maybe it does for other insuiln resistant people, too.

On insulin, by another writer at Berardi’s site:

The waters get muddy when we introduce insulin. Insulin is an anabolic hormone, but it’s one that, if chronically elevated, can lead to diabetes, obesity, and heart disease. Therefore, not surprisingly, with insulin we need to perfect the balancing act; just enough to be anabolic but not enough to cause disease. Therefore insulin concentrations should be relatively low. Now, to clarify, I use the term relative when discussing hormones because it is beyond the scope of this essay to get into the details of what these levels should be for individuals of every age or gender. I am speaking in general terms, when I say that for the most part, the levels in healthy individuals should show this pattern.

Human Growth Hormone – relatively high
Testosterone – relatively high
Cortisol – relatively low
Insulin – relatively low

— “The Anabolic Imperative” by George Parigian

[Note: for women, testoserone levels will be lots lower. Part of the reason women can’t build the kind of muscle mass that Arnold Schwarzenegger or Lou Ferrigno can.]

Insulin in & of itself is not the problem: insulin resistance is. Berardi didn’t say different, I didn’t say different. Ever. What is new to me in Berardi’s approach is that he claims that by proper nutritional timing — which macronutrients (protein, carbs, fats) that you eat when, — you can minimize insulin’s storage of fat (one part of its role as an anabolic hormone) while taking advantage of its anabolic properties re: muscle — i.e., when amino acids are in the blood after eating protein, which is another event inducing insulin secretion. This is why I brought this up: not because I think that “too much insulin” is somehow suddenly magically good for us insulin resistant people, but because this approach, based on a more complete picture of what insulin actually does in the body, leads to some dietary strategies that minimize or reduce fat storage while at the same time maintaining or even (with exercise) increasing lean muscle mass: one avenue towards improving insulin sensitivity.

Note also that when this person challenged my initial post last week about insulin’s role in muscle anabolism, I quoted from four scientific studies — studies published in medical & scientific journals, most of which are peer-reviewed by other scientists before publication, to be sure they aren’t full of nonsense — & the scientists who authored those articles also, every single one of them, said that insulin is anabolic (for muscle as well as body fat). I could have quoted from many more. If anyone wants to look them up for themselves, go to PubMed & search on the terms “protein insulin amino muscle.”

I’m done debating whether insulin is anabolic. Just as I wouldn’t waste my breath debating someone on the question of whether water is wet.

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Insulin index

Posted on Sat, 5 August 2006 by Mel Green

One problem with David Mendosa’s article about the insulin index, which I referenced yesterday, is that the insulin index table he gives doesn’t tell you very much about the foods contained in it. For example, as a correspondent pointed out to me, is the “beef” listed there ground beef with 25 percent fat? or is it a nice, lean sirloin tip steak with only 3 percent fat?

Luckily, I was able to find the original study that Mendosa was writing about: “An insulin index of foods: the insulin demand generated by 1000-kJ portions of common foods” by SH Holt, JC Miller and P Petocz, American Journal of Clinical Nutrition, Vol 66, 1264-1276 (1997).

The full article is much more specific than Mendosa’s “popularization” of it on the foods used & exactly how they were prepared. For example, what Mendosa listed simply as beef is revealed in the full study to be:

Food: Beef steak

Variety, manufacturer, or place of purchase: Lean topside beef fillets bought in bulk from supermarket, trimmed and stored frozen

Preparation: Grilled the day before serving, cut into standard bite-sized pieces, and stored at 4° C overnight; reheated in microwave oven for 2 mm immediately before serving [Table 1, page 1265]

The nutritional composition of the beef, according to Table 2 (page 1267), was 7.7 grams of fat & 42.0 grams of protein (0.0 carb), in a 158 gram serving. (All the foods were tested in 1000-kilojoule servings.) The white fish used in the study (ling fish fillets) was even leaner: 1.0 grams of fat & 56.3 grams of protein (0.0 carb). The other protein-rich foods chosen (cheese, eggs, lentils, baked beans) all had more fat & at least some carb (esp. the lentils & beans).

That kind of detail is given for all the foods tested in the study, & the article gives a very full methodology of how the study was conducted, who the test subjects were, etc. Their analysis included comparing the insulin score with the glucose score that they also calculated based on the test subjects’ blood glucose. (Not the same as glycemic index, but also measuring the test subjects’ glycemic response to the test foods).

Things I found most significant:

Overall, glucose and insulin scores were highly correlated…. However, protein-rich foods and bakery products (rich in fat and refined carbohydrate) elicited insulin responses that were disproportionately higher than their glycemic responses. [from the abstract]

*

[C]arbohydrate is not the only stimulus for insulin secretion. Protein-rich foods or the addition of protein to a carbohydrate-rich meal can stimulate a modest rise in insulin secretion without increasing blood glucose concentrations, particularly in subjects with diabetes (20-22). Similarly, adding a large amount of fat to a carbohydrate-rich meal increases insulin secretion even though plasma glucose responses are reduced (23, 24). [page 1266]

The numbers in parentheses are references to other scientific studies — i.e., these facts weren’t newly discovered in this study, but were already known. The second fact, about adding fat to a carb-rich meal, is pretty relevant to that well-known phenomenon of the glycemic index where sugar-rich junk food ends up having a low GI because it’s also got a lot of fat in it. The fat makes the GI low, but it doesn’t lower the insulin response.

The high-protein foods except the baked beans (which had a lot of carbohydrate) all had among the lower insulin scores of the foods tested, most of which in other categories had a lot of carbs in them. But just like the abstract says, the insulin response to the high protein foods was a lot higher than you’d think if you think that insulin is only provoked by carbs or fat. This is especially apparent with the lean beef & the white fish.

Yes: protein provokes insulin response even without sugar or starch or significant fat being present, and “fish, beef, cheese, and eggs still had larger insulin responses per gram than did many of the foods consisting predominantly of carbohydrate” (page 1275).

The important Western staples, bread and potato, were among the most insulinogenic [provoking insulin excretion] foods. Similarly, the highly refined bakery products and snack foods induced substantially more insulin secretion per kilojoule or per gram of food than did the other test foods. In contrast, pasta, oatmeal porridge, and All-Bran cereal produced relatively low insulin responses, despite their high carbohydrate contents. [page 1273]

No big surprise about the bread & potato. Very interesting about the pasta, oatmeal, & All-Bran, especially since I eat steel-cut oats almost every day for breakfast.

However, some protein and fat-rich foods (eggs, beef, fish, lentils, cheese, cake, and doughnuts) induced as much insulin secretion as did some carbohydrate-rich foods (eg, beef was equal to brown rice and fish was equal to grain bread). [pages 1273-1274]

*

Overall, the fiber content did not predict the magnitude of the insulin response. Similar ISs were observed for white and brown pasta, white and brown rice, and white and whole-meal bread. All of these foods are relatively refined compared with their traditional counterparts. Collectively, the findings imply that typical Western diets are likely to be significantly more insulinogenic than more traditional diets based on less refined foods. [page 1274]

In other words, the more refined the diet, the more insulin you’re probably going to have in your blood after eating. (And the more fat you’re likely to store from any excess carbs you’re eating.)

As observed in previous studies, consumption of protein or fat with carbohydrate in creases insulin secretion compared with the insulinogenic effect of these nutrients alone (22, 30-32). This may partly explain the markedly high insulin response to baked beans. Dried hancot beans, which are soaked and boiled, are likely to have a lower IS than commercial baked beans, which are more readily digestible. [page 1275]

Another call for less refined foods. Again, the numbers in parentheses refer to prior scientific studies.

The results confirm that increased insulin secretion does not account for the low glycemic responses produced by low-GI foods such as pasta, porridge, and All-Bran cereal (33). Furthermore, equal-carbohydrate servings of foods do not necessarily stimulate insulin secretion to the same extent. For example, isoenergetic servings of pasta and potatoes both contained ~50g carbohydrate, yet the IS for potatoes was three times greater than that for pasta. [page 1275]

So if you must have pasta, it’s at least a better choice re: insulin secretion than potatoes.

Similarly, porridge and yogurt, and whole-grain bread and baked beans, produced disparate ISs [insulin scores] despite their similar carbohydrate contents. These findings, like others, challenge the scientific basis of carbohydrate exchange tables, which assume that portions of different foods containing 10-15g carbohydrate will have equal physiologic effects and will require equal amounts of exogenous insulin to be metabolized. [page 1275]

So much for carbohydrate exchange tables. So much for the ADA & American Association of Diabetes Educators truisms (falsisms) that “the quality of carbohydrate isn’t important, the quantity does,” which is what my friend Sylvia was told when she was diagnosed with diabetes.

In the end, I think Berardi is right: if you eat, you can’t avoid insulin secretion — & that’s actually that’s a good thing, since insulin is, it turns out, an anabolic hormone for muscle (as well as for fat). But as an insulin resistant person, I can’t have too much or I continue to get less healthy, not to mention gaining more fat.

So I’ve got to keep working to become more insulin sensitive, so that not so much insulin has to be secreted in order to take care of the metabolic functions I need it for.

I think I’ve already done quite a bit in that direction. I think the programs I’ve decided to take up — Turbulence Training & Precision Nutrition — will help me even further along my health road.

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A new Precision Nutrition customer

Posted on Fri, 4 August 2006 by Mel Green

A couple of weeks ago, when I discovered Craig Ballantyne’s Turbulence Training program, I thought that the cardio & weigh training parts of my person program for health were the only parts that needed tweaking. But John Berardi’s website, especially the new stuff it taught me about the real complexity of insulin’s roles in the body, convince me that my nutrition could use some work as well.

So I sent off for his Precision Nutrition program.

(Unlike some of the other stuff I’ve reviewed here, the Precision Nutrition program comes not in the form of e-books, but actually has to be shipped. Books, CDs, DVDs. So it’ll be a week or two before I can start using it, much less review it here. )

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Insulin: An anabolic hormone

Posted on Fri, 4 August 2006 by Mel Green

Someone on my insulin resistance list took extreme exception to my post there yesterday on insulin response (upon which my blog post yesterday, “Insulin response: It ain’t just the carbs” is based).

I’d quoted from “The Anabolic Power of Insulin: An Interview with John Berardi”:

The current rage in health and fitness is to manage the hormone insulin. But few people really understand this temperamental hormone. You see, insulin is an anabolic giant.

My correspondent didn’t see it at all that way. Insulin, she claimed, is the hormone that “stuffs carbohydrates into fat cells,” an action that she deems as catabolic, not anabolic.

Never mind that catabolic means “breaking down,” & that building fat cells or stuffing things into fat cells isn’t breaking down, but building up — i.e., is anabolic, albeit of fat cells, not the muscle we care about. So she got her terminology mixed up: I did understand what she meant.

She is essentially claiming that insulin’s action is entirely geared toward managing our blood glucose — in ways that aren’t very beneficial to the insulin resistant person or any other person who already has too much body fat. Insulin takes those excess carbs we eat — the stuff that goes beyond what we need to give our brains energy, & replenish the glycogen stores in our muscles — & deposits it into our fat cells.

It does do that. And up until two days ago, I would’ve agreed with her that that’s all insulin really did.

But I would’ve been wrong. And today, I went to PubMed (something she often advises people to do) to back it up.

Several quotations from abstracts of studies located at PubMed based on a search on the terms “protein insulin amino muscle”:

Insulin induces protein accretion by stimulating protein synthesis and inhibiting proteolysis. However, the mechanisms of regulation of protein metabolism by insulin are complex and still not completely understood…. Finally, although the role of insulin has been doubtful and has long been considered to be minor in ruminants and in avian species, this hormone clearly regulates protein metabolism in both species.

[Tesseraud S, Metayer S, Duchene S, Bigot K, Grizard J, Dupont J. “Regulation of protein metabolism by insulin: Value of different approaches and animal models.” Domest Anim Endocrinol. 2006 Jun 30]

*

Despite being an anabolic hormone in skeletal muscle, insulin’s anti-catabolic mechanism in humans remains controversial with contradictory reports showing either stimulation protein synthesis (PS) or inhibition protein breakdown (PB) by insulin…. In conclusion, using amino-acyl tRNA as the precursor pool, it is demonstrated that in healthy humans in the postabsorptive state, insulin does not stimulate muscle protein synthesis and confirmed that insulin achieves muscle protein anabolism by inhibition of muscle protein breakdown.

[Chow LS, Albright RC, Bigelow ML, Toffolo G, Cobelli C, Nair KS. “Mechanism of Insulin’s Anabolic Effect on Muscle – Measurements of Muscle Protein Synthesis and Breakdown Using Aminoacyl tRNA and Other Surrogate Measures.” Am J Physiol Endocrinol Metab. 2006 May 16]

*

Insulin promotes muscle anabolism, but it is still unclear whether it stimulates muscle protein synthesis in humans. We hypothesized that insulin can increase muscle protein synthesis only if it increases muscle amino acid availability…. In conclusion, physiological hyperinsulinemia [high insulin levels] promotes muscle protein synthesis as long as it concomitantly increases muscle blood flow and amino acid availability.

[Fujita S, Rasmussen BB, Cadenas JG, Grady JJ, Volpi E. “The effect of insulin on human skeletal muscle protein synthesis is modulated by insulin-induced changes in muscle blood flow and amino acid availability.” Am J Physiol Endocrinol Metab. 2006 May 16]

*

A reduced response of older skeletal muscle to anabolic stimuli may contribute to the development of sarcopenia [the degenerative loss of skeletal muscle mass and strength in the aged]. We hypothesized that muscle proteins are resistant to the anabolic action of insulin in the elderly…. In conclusion, skeletal muscle protein synthesis is resistant to the anabolic action of insulin in older subjects, which may be an important contributor to the development of sarcopenia.

[Rasmussen BB, Fujita S, Wolfe RR, Mittendorfer B, Roy M, Rowe VL, Volpi E. “Insulin resistance of muscle protein metabolism in aging.” FASEB J. 2006 Apr;20(6):768-9.]

There are others, but this is enough to confirm that the scientific community assumes, as a matter of course, that insulin plays an anabolic (building up) and anti-catabolic (breaking down) role with regard to muscle. A lot of the research has to do with exactly how it does that, & at least one study (the first one above) concludes that it does by preventing by inhibiting the breakdown of muscle proteins, rather than by stimulating the synthesis of new proteins, at least in some states. (I’m sure other studies will be conducted to try to duplicate or refute those results.)

So it turns out that John Berardi is right: insulin is anabolic with regards to muscle. Whether he’s right in some of his specific recommendations, I don’t know, but I sure feel confirmed in my belief that his stuff is worth checking out further. And in feeling that the whole picture of insulin is a lot more complex than insulin being just “the hormone that stuffs carbohydrates into fat cells.”

I don’t know yet what this means in terms of what insulin resistant people like me should do about it. I aim to find out.

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Insulin response: It ain't just the carbs

Posted on Thu, 3 August 2006 by Mel Green

Someone on my insulin resistance forum asked about insulin response to saturated fats.

But it ain’t just the carbs, ain’t just the saturated fat which elicit the secretion of insulin in our bodies. A study on the insulin demand of different foods — which generated something called the “insulin index” — found that “”protein-rich foods … elicited insulin responses that were disproportionately higher than their glycemic responses.” (More on this from David Mendosa.)

I.e., the glycemic index (GI) value of a given food generally can be used to predict that food’s insulin response — but not always. Protein rich foods that provoke very little glycemic response will nonethless provoke insulin response. This is very relevant to people like me who are insulin resistant… & indeed to any person who’s trying to burn off the fat, since one of insulin’s functions is to take excess blood glucose & store it as fat.

Now, I hadn’t really understood this before. Insulin is involved not only in dealing with carbohydrate metabolism (blood glucose), but also with the metabolism of fats & proteins (amino acids). It plays a crucial role not just in fat deposition, but also in muscle growth.

The current rage in health and fitness is to manage the hormone insulin. But few people really understand this temperamental hormone. You see, insulin is an anabolic giant. It’s the most anabolic hormone because it stuffs nutrients like amino acids and carbs into muscle cells to promote growth. But, while it sounds great, getting aggressive with it can lead to serious fat gain. For instance, here are some basics:Insulin is a hormone released into the blood by an internal organ called the pancreas. Insulin functions in many ways as an anabolic or a storage hormone; in fact it’s been called the most anabolic hormone. When insulin is released into the bloodstream, it acts to shuttle glucose [carbohydrates], amino acids, and blood fats into the cells of the body. “Which cells?” you ask. Well, fat and muscle cells are the important ones in terms of quantity. Now, if these nutrients go predominantly into muscles, then the muscles grow and body fat is managed. If these nutrients go predominantly into fat, then muscle mass is unaffected and body fat is increased.

So obviously if there were a way to send nutrients preferentially into muscle rather than fat, trainees would have more muscle mass and less fat mass. That’s the goal of my recommended training and eating programs – to increase the muscle uptake of nutrients preferentially. Isn’t that the goal of every trainee whether they know it or not?

[from “The Anabolic Power of Insulin: An Interview with John Berardi”]

I just came across John Berardi’s site yesterday, & am still grappling with the new information it provides. I had not understood before that insulin had anabolic (building) effects with muscle in terms of shuttling amino acids around, on top of its work shuttling blood glucose around (to the brain or the muscles for energy, or turning excess blood glucose into body fat).

But based on insulin’s anabolic properties, Berardi (Ph.D. in exercise biology & nutrient biochemistry) suggests that the issue is not to avoid insulin release, per se, but to eat so that insulin is working for you, not against you:

Because insulin is a storage hormone, most people think that since insulin stores nutrients, it should be avoided because it has the potential to store fat. This is a mistake for several reasons. First, there’s no way to avoid insulin in the blood. Whenever you eat food, insulin is released.Secondly, if you theoretically could eliminate insulin, you would abolish all of its anabolic effects and its ability to store energy in the muscle. In fact, type 1 diabetics don’t produce insulin and as a result, if left untreated, they die.

But don’t go the opposite route, either. If blood levels of insulin are always highly elevated, trouble results. Chronic elevation of insulin leads to large amounts of fat gain, risk for cardiovascular disease, and ultimately to type 2 diabetes. This second type of diabetes is characterized by obesity, cardiovascular disease, and the poor ability of the muscle to store nutrients, which leads to muscle wasting and tons of fat storage. This is called insulin resistance.

So my point is that you need insulin, but you must learn how to balance the anabolic effects against the fat storage effects; to trick it into making you muscular while making you lean at the same time. And this is done two major ways; first by increasing insulin sensitivity in the muscle while decreasing insulin sensitivity in the fat cells and, second, by controlling the insulin released during specific times of the day.

[same source]

Which is what the nutritional plans Berardi designs are all about. Anyway, if anyone wants to follow this up further, there’s a source for you.

Another article at the same site is also informative: “Optimizing Insulin Sensitivity and Body Composition Through Diet and Exercise” by Jason Feldman.

Again, this is relevant to anyone who is trying to get rid of that unwanted body fat.

Posted in Fat loss, Insulin resistance | Tagged , , , , , , , , , | Comments Off on Insulin response: It ain't just the carbs

John Berardi on nutrition

Posted on Wed, 2 August 2006 by Mel Green

Since learning about Turbulence Training last week, I’ve been subscribing to TT creator Craig Ballantyne’s Turbulence Training blog. Today that resulted in a nice little nugget — a nugget that led to a pretty rich vein. The nugget was Ballantyne’s offhand suggestion to check out a “nutrition blog” at John Berardi’s website. The vein proved to be all that really is at that website: a fount of articles, fully backed up by research, on good nutrition for muscle building, fat loss, & fitness.

John Berardi holds a Ph.D. in exercise biology & nutrient biochemistry, & works extensively on performance nutrition with various sports teams, Olympic training centers, & individual athletes, particularly in Canada. He’s also worked with a lot of regular people who are just trying to get healthier. He himself has been involved in several sports including powerlifting, bodybuilding, rugby, & track & field.

He’s also got a program called <Precision Nutrition, “our complete start-to-finish diet guide designed to get you the body you never thought you could have.” It’s got good reviews based on my web research, & is in use with a variety of athletic teams & trainers. I plan to check into it.

Meanwhile, with all the host of articles on his main website, I’ve found a new source of topnotch nutritional information that’s already adding to my understanding by leaps & bounds. I’ll be reviewing some of that info here as I read through it.

Posted in Nutrition | Tagged , | 1 Comment

Carbohydrates & depression 2

Posted on Thu, 27 July 2006 by Mel Green

I do pretty well avoiding the black hole nowadays. Over the years (I’m now 47) I’ve worked through a lot of the emotional components that stem from my own family background & life history, & although I stay informed, I’ve learned not to follow the news too closely because if I’m not careful it can send me into a tailspin pretty fast. I also tend to take a lot on & to expect myself to be productive in one way or another all the time, so I’ve learned to pull back & not expect so much of myself.

But there have always been physical components to my experience of depression & despair, such as getting enough rest (sleep, as well as vege-out time) & also how I eat. My partner noticed pretty quickly after I started eating low GI & making other dietary changes, which included eating fewer carbohydrates than I used to — now at what I call a moderate carbohydrate level (100-125 grams per day) — that my mood seems more stable. I don’t tend to get as irritable or ill-tempered, or to get depressed.

But — on the few occasions where I have started going into a slide towards the pit, even though there have been issues that were bugging me at the time such as finances (perenially broke since February; thankfully, that will be changing with our move to a new & less expensive apartment this week), every occasion has been marked by having for one reason or another eaten slightly lower amount of carbs.

This isn’t a case of “I’m feeling bad, I need a candy bar or a piece of cake to console myself & raise my serotonin levels” (& also cause a spike in blood sugar, to be followed possibly by a hypoglycemic episode, etc. etc.). Probably serotonin levels have something to do with it: but what I need when I feel that way isn’t a candy bar, but maybe an apple, or half a cup of steel cut oats, each taken with some protein… & mostly simply because I had missed getting enough carb in some meal during the day. Doesn’t happen often anymore, because once I became aware of the problem, I became a lot more careful about meal planning, to stay within the range of carbs per day that works well with me. Eating a sufficient amount of carbs as part of a healthy, balanced diet has become as essential a part of supporting myself against depression & despair as getting enough rest, getting enough relaxation & fun time, & not becoming obsessed with the bad news in the world.

Over the time since I began to change my eating habits (late December), I’ve come to recognize that low carb works well for a significant number of people. It doesn’t work for me, any more than the high carb of SAD (the Standard American Diet) did. SAD sent me on up & down swings (no doubt matching my blood sugar spikes & dips); low carb eating takes me down to places in my mind that are debilitating & sometimes downright dangerous for me.

For me, if I go too low in my daily carb consumption, there’s a kind of sensation I feel throughout my body that’s hard to describe… kind of a zapped-out, leached-out feeling. Whereas if I have too many carbs (even if they’re low glycemic), there’ll be a kind of zinging, frantic feeling. Either of those can presage a trip to the edges of the pit for me, often starting with irritability or an explosion of temper — which can be soon followed by implosion & full-scale entry into the pit, unless I take immediate countermeasures like being by myself in quiet, & getting lots of sleep.

Oh yeah, & getting just a little bit more oatmeal, or an apple, or some other low glycemic carb.

I think when I eat too many carbs, as I routinely did before last December, that cautions about blood glucose swings & short-term stimulants that backfire long-term are well-founded & accurate. But these causations do not fit the circumstance of going into a black hole for the lack of one orange or two Wasa wholegrain crackers in a given meal — even though I ate my eggs, my fish, my carrots & onions & kale & celery, my extra virgin olive oil, my chicken, my walnuts. The fact is, the way I eat now, & have been eating for months, keeps my blood glucose level: there are no wild swings, no rebound effects.

My best guess is that my trips to the edges of the pit have to do with the minimum amount of carbohydrate that my body demands in order to manufacture enough serotonin. Perhaps it has something to do also with how much I exercise, & I’d need less if I exercised less. Or maybe it’s just an individual thing, having to do with blood type, body type, genetics, individual history… who knows.

Regardless, anyone who counsels me — as the low-carber of my acquaintance did — to eat low-carb in order to support myself against depression is flat wrong.

Posted in depression, Nutrition | Tagged , , | 2 Comments