I didn’t know anything diet or metabolism or how prehistoric humans ate when I first read BFL. But if I’d only read the book with a more critical eye, I might have questioned its assertions.
Little Meals throughout the Day?
For example, Phillips claims it’s better to eat small, frequent meals throughout the day, or "graze." He has some iffy reasons for doing so.
On p. 44 of Body for Life, Phillips states,
It’s revealing to take a look at the animal kingdom and notice the relationship between creatures’ eating patterns and their body “types.” At one end of the spectrum are animals that load up on large amounts of food at one “meal,” then go for days, weeks or even months without eating at all. Bears are a prime example of this type of infrequent feeder....At the other end of the eating-pattern spectrum are the frequent feeders: animals that eat almost constantly but in far lesser amounts. Horses, buffalo, elk--I call these grazers. Relatively speaking, they have very low body fat and lots of lean muscle. It seems pretty clear that we should graze, not binge, don’t you think?
Phillips is confusing association with causation: he’s saying that frequency of eating affects body fat level. But by using the same reasoning, we could say that the binging bears are omnivores and the grazing horses, buffalo and elk are vegetarians, therefore we should be vegetarians to be lean and muscular. In fact, large cats like lions and cheetahs are lean, muscular animals that gorge themselves after kills. Maybe the fact that bears hybernate has something to do with their binge eating and fat storage?
Phillips again recalls the practices of our ancient ancestors:
If you look at how humans evolved, you’ll see our long-lost relatives were ‘frequent feeders’, not bingers.
He doesn’t cite a source for this (or anything else) in BFL. In contrast, Dr. Loren Cordain, who has had a long career studying our stone-age ancestors, says in The Paleo Diet Newsletter,
The most consistent daily eating pattern that is beginning to emerge from the ethnographic literature in hunter-gatherers is that of a large single meal which was consumed in the late afternoon or evening. A midday meal or lunch was rarely or never consumed and a small breakfast (consisting of the remainders of the previous evening meal) was sometimes eaten.*
This makes more sense: prehistoric humans didn’t have a constant supply of snacks, did they? Phillips says himself on p. 45 of BFL,
[Our ancestors] did not have a consistently abundant supply of food. They were hunters/gatherers and, more recently, farmers, who sometimes had plenty to eat but regularly endured periods of time when there was little or nothing to eat.
I don't know whether it's best to eat frequently or not. I just eat when I'm hungry and stop when I'm full (usually). However, I believe the real reason for frequent meals has nothing to do with our cave-man ancestors, and everything to do with blood sugar levels.
As you probably know, falling blood sugar can make you feel hungry. What causes it to fall? Even in normal people, a high-carbohydrate meal makes blood sugar rise and then fall quickly. Check out this graph showing normal blood sugars:
The blue line shows average blood sugar of the group after eating a high-carb breakfast at 7:30--you can see the spike even in normal people. In people with a metabolic problem, blood sugar can "easily exceed 180" on a high-carb breakfast of "healthy whole grain" oatmeal--an "authorized" food on BFL. At that level (the top edge of the graph), your blood sugar has a long way to fall. When it does, you get hungry, even if you're normal and healthy, and it's time to...eat another meal.
Of course, a BFL meal consists of both lean protein and carbohydrate, which could affect blood sugar levels for the better. But if you are hungry every few hours, that suggests to me that the protein isn't having much effect on your blood sugar level.
Does the small size of the meals make it necessary to eat often? If so, why not save yourself some trouble and just eat three normal size meals a day? I think it's because your blood sugar will go up even further with a double serving of carb at one sitting. And notice that the grazers Phillips lists are all carb-eaters.
Before and after photos are great, and I think it's reasonable to be a little suspicious of an unhealthy looking person giving health advice. (Phillips looks very fit and healthy, BTW.) But it's worth knowing how they got to those after photos. Clearly BFL works in some cases--it worked for me for a few years. However, I believe I could have saved myself a lot of workouts, a whole lot of cooking, and some health problems both niggling and significant (which would have been caused by any high-carb diet, not just BFL) if I had examined the program more closely.
*Copied from the Heart Scan Blog, November 23, 2009, http://heartscanblog.blogspot.com/2009/11/paleo-approach-to-meal-frequency.html