diet and exercise reduce diabetes)
Prevention: The Diet
people still believe that eating too much sugar causes diabetes.
This misconception arises because diabetes is diagnosed by measuring
blood sugar (glucose). But dietary sugar is only part of the
picture. According to two recent Harvard studies, a diet rich
in certain high-carbohydrate foodsthose low in fiber and
with a high glycemic index (see below)increases the risk
of Type 2 diabetes, at least in those
predisposed to it.
study tracked 65,000 female nurses (age 40 to 65); the other
followed 43,000 male health professionals. Over the course of
six years, a total of 1,438 developed diabetes. Men and women
whose diet had a high glycemic index and low fiber content more
than doubled their chance of developing diabetes. Foods that
seemed to pose the greatest risk were white bread, white rice,
potatoes, and sugary soft drinks. In contrast, whole-grain breads
and cereals (rich in fiber and with a lower glycemic index)
appeared to reduce the risk of diabetes. Fruits and vegetables
didn't seem to have an effect, good or bad.
researchers suggested that excessive amounts of carbohydrate-rich
foods with a high glycemic index put pressure on the pancreas
to produce more of the hormone insulin, which stimulates the
body's cells to take in and store glucose. Over time, the body
may become resistant to insulin. In such insulin-resistant people,
the cells become less and less sensitive to insulin. This is
characteristic of Type 2 diabetes. Of course, not everyone on
such a low-fiber, high-starch diet develops diabetes. There
seems to be a genetic predisposition to diabetes, which may
be exacerbated by this kind of diet. Without these dietary factors,
the men and women in these two studies might have developed
diabetes later in life, or perhaps not at all.
is probably the leading risk factor for Type 2 diabetes. Family
history of the disease, advancing age, and lack of exercise
are other important factors.
study also found that the mineral magnesium has a protective
effect against diabetes. A few studies have suggested that this
mineral improves insulin sensitivity. But since whole grains
are rich in magnesium, it's hard to say whether the proposed
benefit is due to something else in the grain (notably its fiber)
or the mineral.
Bottom line: A diabetes-prevention diet, if there is one, is
the same low-fat, high-fiber, semi-vegetarian diet that is known
to lower the risk of heart disease and cancer. The Harvard studies
simply underline the importance of choosing whole-grain products,
as opposed to highly refined, low-fiber grain products such
as white bread, in order to help control blood sugar. Such a
diet helps in weight control. It also provides the vitamins,
minerals, and other nutrients you need to help prevent chronic
diseases, including, perhaps, diabetes.
The glycemic index indicates how fast a high-carbohydrate
food is digested into glucose and how much it causes blood
glucose to rise. The index doesn't depend merely on whether
the carbohydrates are simple (sugars) or complex (starches).
Many factors come into play, including the amount of fiber
and fat in the food, how refined the food is, how fast the
food is digested, whether it was cooked, and what else is
eaten with it. Table sugar and honey have a high glycemic
index (meaning they have a strong effect on blood sugar).
But so do raisins, corn, potatoes, carrots, white bread,
instant rice, and most refined cereals. Though sweet, apples
and peaches, as well as beans, grapefruit, and peanuts,
have a low glycemic index. Pasta gets a middle rating, as
does oatmeal. There is no reason
to avoid foods with a high glycemic indexmany are
very nutritious. Even people predisposed to diabetes, or
with the disease, can eat these foods in moderation.
info on glycemic index
on Diabetes Prevention
Reference Source 89, 98