PureInsight | January 6, 2008
My dislike of many starchy carbs like bread, potatoes, rice, pasta, and
breakfast cereals is based on a body of evidence that suggests that the
glut of insulin that the body produces on eating them can speed our
path to conditions such as obesity and type 2 diabetes.
And, despite all this talk about their being good for you, the fact
remains that carbs leave a lot to be desired on the nutrition front,
Individuals often spring to the defense of starchy foods on the basis
that some supposedly healthy populations eat a lot of them, proving
such foods can't be unhealthy. The argument usually goes along the
lines of: "If starchy foods are so bad, how come the
Mediterranean/Chinese/French diet which is full of pasta, rice, and
French bread is so healthy?"
First, I think that we sometimes have a very stereotypical image of
some traditional diets. The French do eat French bread, but most of
their diet is actually made up of quite natural, unprocessed foods. The
same is true of the Italians who, when they eat pasta, actually tend to
eat it as a starter rather than as a main course.
And while the Chinese do eat rice, they eat a lot of other foods too,
including vegetables, fish, and meat. I haven't been able to find any
good data on the overall glycemic index (GI) and glycemic load (GL) of
the diets of these or other nations. If we had some, maybe we'd see
that the stereotypical view we have of their diets is far from accurate.
But even if it's true that these nations do eat a stack of starch and
at the same time enjoy good health and longevity, what this really
tells us may not be obvious. When examining the effects of food on
health, it's important to isolate the factor you want to assess and
keep, wherever possible, everything else the same. One way of doing
this is to look within a population to see what relationships there are
between the diet and the health of the individuals.
The fact is that health and longevity are the products of a number of
different factors, and some of the negative influences involved may be
offset by more positive ones. For instance, perhaps rice does make up a
fair proportion of the Chinese diet, but maybe the Chinese are
generally an active bunch, and this may be helping to protect them
against any damage that rice might otherwise wreak in the body.
The studies that have been done in the area show quite compelling
evidence that we eat a high GI/GL diet at our peril. Just last month,
we saw the publication of two studies, which have linked higher carb
consumption with an increased risk of type 2 diabetes.
Shortly after I had written about these studies on my blog, one
commentator claimed that high GI foods can't be bad for us because the
Japanese eat rice and are healthy. The reality is that such a
simplistic deduction is no more scientific than claiming that because
your grandpa Joe smoked and lived to be 100, smoking cannot be harmful