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Appetite For Construction
Dec 5 2003

By Dr. John M Berardi, Ph.D.
First published at www.t-mag.com.

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Massive Eating Special Edition

The following is a collection of questions related to JB's Massive Eating series.

Q: I’m a long-time follower of P+F:P+C [protein + fats:protein + carbs]. The results are amazing, but I have several questions. First, since fat is absorbed in the lymphatic system vs. the circulatory system, why is it bad to have elevated levels of insulin in the blood?

A: Fat digestion and absorption is complex. First, dietary triacylglcerols (3 fatty acids+1 glycerol), due to their hydrophobic (water fearing) structure, are emulsified by a number of compounds in the GI tract and digested by lingual lipase and pancreatic lipase.

While digestion begins in the stomach, it's finished in the small intestine where diacylglycerols (2 fatty acids+1 glycerol), monoacylglycerols (1 fatty acid+1 glycerol), and free fatty acids are formed and join with bile salts to form micelles. These micelles are now hydrophilic (water loving) and can interact with the intestinal cells in order promote lipid absorption.

Once absorbed into the cells, longer fatty acids are rounded up to again form triacylglycerols and these triacylglycerols are processed, form chylomicrons/lipoproteins, and are sent into the lymphatic system. But shortly after absorption into the lymphatic system, the fats reach the portal blood (blood that circulates to the liver).

Interestingly, while the longer fatty acids go through this route, the shorter fatty acids go right into the blood stream. Therefore, some fats go straight to the bloodstream, others get there a little more slowly. The peak level of fat in the blood usually occurs between 30 minutes to 3 hours after a fatty meal (that's a wide range based on the type of fat and the amount of fat ingested).

So I see your point—fat appearance is slower than insulin appearance. But remember, glucose is up right after the meal and back down to baseline at about the 2 hour mark. Insulin response is a bit protracted and is elevated above baseline for at least 3 hours after a meal. But the appearance of both in the blood are slowed by the presence of fat in the meal.

So, knowing that fat appearance can be peaking (on average) 1-2 hours after ingestion, you can see that there will be a decent overlap in the time courses of appearance of fats, glucose, and insulin in the blood when a significant amount of carbs and fat are ingested together. Add to this the fact that carbohydrate and fat ingestion seems to lead to a synergistic increase in insulin response, and we're talking about some kickin' insulin.

Therefore, you get the duo I suggested you avoid (C+F+insulin kickin' in the blood), a combo that's probably a no-no for optimal body composition.

Q: Why isn’t ingesting fructose + fat a good idea since fructose doesn’t trigger insulin release and is transported via blood to the liver?

A: First, if you've followed my writing since my "Massive Eating" article was published (way back in March of 2001), you'll know that I don’t even suggest that anyone should follow massive eating year-round. Rather, it's a good strategy for, what some might call, "clean bulking" (i.e. eating good food while trying to pack on lean mass while minimizing fat mass).

So be careful with the "why can't we..." questions. And be careful not to extrapolate too broadly about massive eating's utility...it was designed for the unique situation where a hard training weight lifter wants to gain quality lean mass with minimal fat mass.

With that said, I don't think fructose is a big problem at all. After all, it's slowly absorbed (because it goes to the liver first and requires a longer processing time) and doesn't cause a BIG insulin release (there is an insulin response though). Therefore, a piece of fruit with a P+F meal is probably okay (just like some veggies with a P+F meal is also okay).

However, remember that you rarely ever eat just fructose (unless you're drinking high fructose corn syrup and this, my friend, does produce an insulin response): fruit has other carbohydrates as well.

Q: I hate to ask, but is there any scientific evidence to support eating P+C or P+F? I need some ammo so I can argue with some of my nutrition-student friends.

A: There is no direct scientific evidence that minimizing your fat intake while eating a P+C meal OR minimizing your carb intake while eating a P+F meal will help you gain lean mass while minimizing fat mass gain. NONE!

But there is no evidence refuting it, either. And for those who'd like to point out the overweight women study, I'll head you off at the pass. Yes, there was one study showing that this idea didn't work in overweight women on a calorie-restricted diet. Uh, what does that mean? We can't really make a good comparison between that situation and one in which individuals are training hard, consuming a hypercaloric diet, and trying to gain mass, can we?

This time, there's no omniscient scientist around to tell us the right answer. So, with the lack of evidence either way, people have to decide whether the strategy has merit or not, based on the theory. Or they could just look around at the thousands of people that have tried the ideas out and see what they've experienced.

Quick question...just because there is a lack of evidence in either direction, does that mean the idea can't work? I'll let you figure that out yourself. But first, a hint...before Newton had his apple, where was gravity?

While the Massive Eating plan isn't perfect (no human attempt at manipulating physiology is), I believe it provides a functional way to consume an abundant amount of micronutrient dense, glycogen-replenishing carbohydrates and metabolism altering, hormone-stimulating fats, and muscle-building proteins while simultaneously preventing excessive hyperinsulinemia and excessive fat gain.

Q: If at all possible, please explain in detail how P+F is handled in the body.

A: This is a toughie because I don't know exactly what you're asking. However, I'll address what I think you're asking.

As mentioned earlier, the inclusion of fat in a meal, leads to slowed gastric emptying. Therefore, adding fat to a high-protein meal may effectively slow the rate of the protein absorption, creating something analogous to a time-released protein. This would make the P+F meal ideal for bedtime snacks, especially if you choose the appropriate protein source (see "Bedtime Story").

Just don't use this combo during the post workout period. That’s when you want bangin' insulin concentrations and rapid protein absorption.

The other consequence of P+F is glucagon. Since glucagon is a regulatory hormone responsible for providing energy to the tissues, it’s classified as a catabolic hormone. Glucagon stimulates the breakdown of stored glycogen into glucose in skeletal muscle and in the liver; stimulates the breakdown of fats into fatty acids in adipose tissue; maintains the liver's output of glucose from amino acid precursors; and leads to the formation of ketone bodies from fatty-acid precursors in the liver—all catabolic events designed at dipping into your energy reserves to provide fuel.

A protein-only meal increases the release of glucagon (in order to stimulate the liver to produce glucose to normalize blood sugar). Since fat does nothing to directly mitigate the effects of a protein meal on glucagon release while carbohydrates decrease this response, some have speculated that a protein-only meal or a protein-plus-fat meal is a no-no since the glucagon release may promote the manufacture of glucose from all those ingested amino acids.

While this may be true with a high protein diet that also lacks sufficient dietary carbohydrate, I believe that the destruction of amino acids will be minimal if the body has sufficient carbohydrate reserves in the liver. In this case, glucagon will tend to make more of the necessary blood glucose from stored glycogen than from ingested amino acids.

Sure, some of those aminos will be destroyed. But you've gotta’ get your fat in sometime and if you're eating enough protein in your diet, there will be plenty left to keep you growing. Besides, although fat does not necessarily mitigate the glucagon response directly, the fact that fat slows the intestinal transit of the protein indicates that over time, the glucagon response to the same protein meal will be less since there are less amino acids being absorbed per unit time to stimulate glucagon release.

Add to this the fact that glucagon might actually promote some fat loss after P+F meals and we might just be able to make friends with glucagon after all.

Oh yeah, and don't forget that my good friend and colleague Lonnie Lowery has pointed out that fat present in protein meals may help maintain Testosterone levels post-prandially (after eating).

Q: Any new ideas for making Massive Eating more effective?

A: Yep! I've been playing around quite a bit lately with the idea of nutrient timing (i.e. when certain nutrients are fed throughout the day). My PhD dissertation has focused on this topic and therefore, after my immersion in the literature, a few things are clear.

First, the efficiency of glycogen resynthesis is dramatically improved after exercise (duh, nothing new here). But, while this is nothing new, it’s interesting to note that you can probably get most of your depleted muscle glycogen back within the 6 hour post-exercise period, even if you're an endurance athlete depleting away a lot of carbohydrate.

Therefore, with the increased efficiency of glycogen resynthesis during the post-exercise period, it makes sense to feed most of your daily carbohydrate during this time. To further support this idea, new data have been emerging that demonstrate that during the post-exercise period, regardless of what you eat, the body shifts to a fat burning state. In other words, the body burns fat almost exclusively while storing all the carbohydrate it gets.

So if you're following along, it should be clear that you can pack the muscles and liver full of glycogen during the post workout period while burning fat like crazy. For those of you with your thinking caps on, perhaps you should eat all (or, at least, most) of your daily carbohydrate energy during the few hours post workout.

Of late, I've been employing this strategy with fantastic results. What I've been doing with many of my athletes (even endurance athletes) is suggesting that they consume P+F meals throughout the day on non-training days and P+C only during the first few hours post-exercise.

More specifically, their P+F meals come in the form of complete protein (about 30-35% of total dietary energy on workout days) and a mixture of different fats (about 30-35% of total dietary energy on workout days - with the total daily fat breakdown being about 33% saturates, 33% monounsaturates, and 33% polyunsaturates) along side a big helping of vegetables (and/or small amounts of fruit).

Again, these types of meals are consumed all day on non-training days and outside the workout and post workout periods on training days.

The workout and immediate post-workout drinks, of course, consist of sipping a protein and carbohydrate blend. And the one to two (depending on goals, zero to one P+C meal if leaning out and one to two if trying to gain mass or if you're an endurance athlete) post workout meals would also consist of P+C (the amount of carbohydrate should make up the remaining 30-35% of dietary energy).

Therefore, if you're familiar with the original Massive Eating article, you recognize the P+F and P+C strategies; I haven't really altered them. However, what I've done is shift them around throughout the day by recommending P+C meals during the workout drink and throughout the first few hours after the workout (i.e. post-workout drink and 1-2 meals post workout).

Believe it or not, with this system, many of my trainees have actually achieved the ever-elusive goal of simultaneous muscle gain and fat loss.