On Thu, 26 Jun 1997, Gary Jackson wrote:
> Dr MacDougall very kindly posted this reply:
>
> >Great review of the literature. However, every health organization that
> has reviewed the scientific literature has come to the conclusion that
> we should eat less fat and more unrefined carbohydrates in the form of
> starches, vegetables and fruits.
Fallacy of appeal to authority; *petitio principii* (begging the
question). We all know what the health organizations have
concluded. The question is whether their conclusions are
actually supported by the literature that they have reviewed.
> If you look at the world picture it is
> kind of hard to come to the conclusion that high carbohydrate diets make
> you at higher risk of disease and obesity. If carbohydrates were bad for
> people then the Japanese living in Japan on a rice-based diet would be
> fat and sickly.
If we look at the world picture, then we must also wonder why the
French, who exercise little and eat plenty of fat, are *not* fat
and sickly. I can't comment on the Japanese, as I don't really
know much about what they eat, although I question whether
"rice-based" diet is accurate. Does this mean that they get most
of their calories from rice? More than 50 percent? I have read
that they also eat more fish than we in the West tend to do. In
addition, they are a relatively isolated breeding population,
increasing the chances of genetic adaptations that *cannot* be
generalized to human beings in general.
> If high-protein diets, which means meat, egg, and
> dairy products, were so good for us then people who subsist on these
> foods (most Americans) would be the thin and healthy, and vegetarians
> would be fat and sick. In general, the opposite is the case.
But "most American" also consume lots of carbohydrates with their
fats and proteins. Fat-laden starches are common, and it's a
good guess that these cause much of the trouble. French fries,
potato chips, fried rice, pasta with rich sauces, baked goods
impregnated with trans fats.
> Therefore, eating as much as you want (but not more than you
> want) of a healthy low-fat, no-cholesterol diet lowers three important
> risk factors for heart disease--cholesterol, triglycerides and body
> weight.
Total cholesterol is no longer considered a primary risk factor,
but the ration of total to cholesterol is. I wonder how that
McDougall diet affects that ratio?
I have a colleague who has been using a diet like the McDougall
diet for years. He is strict about keeping his fat intake at 10%
of calories. To keep it at this level, he has to eat relatively
little protein, especially animal protein. He eats plenty of
whole-grain products and potatoes, fruits and vegetables. By
means of this diet, he did bring about a 20% decrease in his
total cholesterol, which had been elevated. His HDL levels,
however, have dropped even more sharply, which is a major concern
for both him and his cardiologist. He is a dedicated distance
runner, logging 7 to 10 miles per day but plagued by injuries,
sprains, etc.
> I think the Japanese example is interesting, and I have asked Dr MacDougall
> if their health may be attributed to their relative lack of gluten and
> lactose and the abundance of fish in the diet, rather than the
> macronutrient composition of the food. I also referred him to the Paleo
> Symposium list archives. Has anybody seen the debate with Sears? I have not
> told him that I was posting his replies to this list, but I figure the more
> we can cross reference diet ideas from all quarters, hopefully, the better
> off we shall all be.
I agree. I think it would be *very* interesting to learn whether
a person who has done well with a low-carb diet would also do
well with the McDougall diet.
Todd Moody
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