Hey all, I truly believe high carb diets are passe. Want evidence, want proof? Read this passage from Dr. Sears in the Zone files.
By: Dr. Barry Sears
Next article: Monday, July 6, 1998
Good science predicts the future. If you do A, then invariably B happens. Throw a rock
into the air, and invariably it comes down. Risk factors for heart disease are not quite
as predictable, but they are becoming more predictable. A recent article in the
Journal of the American Medical Association (JAMA 279: 1965-1991 )
confirms that fasting insulin is the best predictor of future heart disease. This was a
prospective study because the participants starting out had no trace of heart disease.
They were followed for many years so that various risk factors could be evaluated in
their ability to predict the future (i.e. who would get a heart attack).
We are told that cholesterol is the villain of heart disease. Yet nearly 50 percent of the
people hospitalized with heart disease in general have normal cholesterol levels. Then
there is good and bad cholesterol. The bad cholesterol known as low-density
lipoproteins (LDL) is considered our newest foe in the battle against heart disease.
That's why everyone in America is being advised to take drugs for the rest of their
lives that lower LDL cholesterol levels.
However, this study shows a very different picture. In predicting the likelihood of a
heart attack, fasting insulin levels were 2.3 times better predictors than LDL
cholesterol levels. In fact, triglycerides were 37 percent better predictors of future
heart disease than LDL cholesterol levels.
Why is this important? The only drug known to medical science that can reduce both
fasting insulin and triglycerides is called the Zone Diet. If good science says that
increased insulin predicts the development of heart disease, then the same science
predicts that lowering insulin will dramatically reduce the development of heart
disease. But that is why I developed the Zone Diet.
Answer to general comments about the Type 2 study
Let me take this opportunity to answer several of the comments received about our
Type 2 diabetic study. First this was a cross-over experiment. The patients were
maintained on the same approximate calories that they had been eating the previous
year on their ADA diets, but now with a different ratio of protein to carbohydrate on
the Zone Diet. A cross-over experiment eliminates any biological differences between
populations and therefore gives a stronger results.
Second, the presented data is only one of three studies we have completed with this
same physician group. Basically, all three studies give almost the identical data.
Third the Zone Diet is about eicosanoid modulation mediated through better insulin
control. This is why EPA and GLA are always included in our research studies since
they are the precursors of eicosanoids.
Fourth, the "increases" in LDL are those associated purely with measurement errors.
LDL is never directly measured. It is a mathematical composite based upon the
measurement of total cholesterol, HDL cholesterol, and triglycerides. For all intents
and purposes, the LDL levels did not change. As shown in my weekly article above,
fasting insulin levels are far better predictors of future development of heart disease
than is LDL cholesterol levels. However, it is well known that decreases in the
triglyceride to HDL cholesterol ratio dramatically alter the size of LDL particles from
small dense atherogenic particles to larger non-atherogenic LDL particles. The change
in the TG/HDL in these subjects indicates that such a transformation of the LDL
particles has taken place.
Fifth, I agree that exercise is an important parameter in lowering LDL levels. We
purposely told these subjects not to drastically change their exercise habits in order
not to confound the study.
Sixth, studies done by Dean Ornish on cardiovascular patients following a strict
vegetarian diet (with intensive exercise and stress reduction) indicate TG/HDL ratio
increases. This has been confirmed by other investigators.
Thanks to everyone on Zone Central and in the Ask the Doctor section of the Zone Files
for their interest and their questions about the study. I read every one of them.