Biology Dictates Diet Success
Low-Glycemic-Load Diet Best for High-Insulin Secretors
WebMD News Archive
No ‘One Size Fits All’ Weight Loss Diet continued...
Low-glycemic-load diets are often called "slow-carb" diets. The idea
of these diets is to avoid starchy and/or sugary carbohydrates -- such as white
potatoes or white rice -- and to eat lots of fruits, nonstarchy vegetables,
legumes, and whole grains.
It's an offshoot of high-fiber diets that cut cholesterol and heart disease
risk, says David J.A. Jenkins, MD, PhD, DSc, director of the clinical nutrition
and risk factor modification center at St. Michael's Hospital, Toronto, and
professor of nutritional sciences at the University of Toronto.
"Many of the things we use in our high-fiber diet -- such as barley,
oats, and psyllium -- have significantly lower glycemic indices than their
low-fiber counterparts," Jenkins tells WebMD. "The sticky parts of
fiber keep your blood sugar down and your cholesterol down. Two birds are hit
with one stone."
Studies of the low-glycemic-load diet get mixed results. The new study
offers an explanation, says Stephen Cook, MD, assistant professor of pediatrics
at the University of Rochester, N.Y. And the findings may explain why a diet
that works at one stage of life does not work later in life.
"We know insulin sensitivity changes over time," Cook tells WebMD.
"People in their 20s and 30s are much more sensitive than older people. So
in looking at this data, I think it is important to keep in mind the fact that
adults go through different developmental stages, just as children do."
Cook says there's still no good clinical test for insulin secretion. But
Fernstrom suggests that the current three-hour glucose challenge test could be
adapted to a 30-minute version acceptable to most patients.
"If the prediction made in this study holds out with further study, this
could be a very useful tool," Fernstrom says. "This study shows that
everybody who is fat does not have problems with glucose and insulin, but some
do. So maybe we can identify a subgroup of people where we can say, 'This kind
of diet could work really well for you.'"