New studies indicating a low-fat diet does
not reduce the risk of cancer and calcium supplements
do little to prevent broken bones are unlikely to change
consumers' habits and may only add to confusion about
the link between diet and health.
In the last year, researchers have released a series
of medical studies that fly in the face of conventional
wisdom, which holds that weight loss, nutritional supplements
and diets low in fat and calories help fight disease and
prolong life.
But three studies in the Journal
of the American Medical Association published earlier
this month showed that women who ate less fat and more
fruits and vegetables did not reduce their risk of cancer
or heart disease. And theNew England
Journal of Medicine found that calcium and vitamin
D supplements were unlikely to prevent broken bones in
women as they age.
The research comes on the heels of statistics published
last year that questioned the U.S. government's assertion
that obesity causes nearly as many deaths as smoking.
The studies prompted headlines suggesting consumers would
take the news as carte blanche to eat as they please,
but experts said that was unlikely.
"Consumers are used to the fact that there are often
multiple medical studies coming out that often have conflicting
findings," said Michael Allenson, a principal at food
industry consulting firm Technomic. "Until they see a
greater consistency ... they are likely not to make a
change."
Consistency, however, appears to be a long way off as
theories about diet and health are constantly changing.
In the last two decades, fats and carbohydrates have alternately
been praised and demonized by health experts. Most recently,
fear of carbohydrates like pasta and bread led to a boom
in low-carb, high-protein diets in 2004 that quickly vanished.
The headline-grabbing studies against a background of
diet trends like low-carb, low-sugar and low-fat forces
consumers to sift through masses of conflicting as well
as confusing information and ultimately draw their own
conclusions.
"The public gets information in little, fragmented pieces
through the news," said Dr. Walter Willett, a nutrition
professor at Harvard University's School of Public Health.
"If that's really all they are getting, it is extraordinarily
difficult to make some sense out of what's there."
Adding to the confusion, according to some, is that while
some consumers take their long-term health into consideration
when eating, those concerns are typically outweighed by
a preoccupation with saving time and money.
"The real problem with health is that there is no immediate
payback," said Harry Balzer, vice president with The NPD
Group, which tracks consumer eating trends. "If I have
low-fat milk today, what do I get? Did it save me time,
did it save me money? The feedback is going to get to
you 40 years from now."
In addition, Allenson said, consumers usually go on diets
so they can lose weight, not so they can prevent disease.
"That's not the only reason why people go on diets or
eat low-fat foods," Allenson said. "A lot of people are
looking to lose weight because they do feel better about
themselves."
In the meantime, while researchers duke it out over the
long-term benefits of diet and exercise, experts said
consumers can rest assured that the conventional wisdom
about maintaining a healthy weight and eating a balanced
diet is more likely to help than hurt.
"What we know about diets hasn't changed. It still makes
sense to eat lots of fruits and vegetables, balance calories
from other foods, and keep calories under control," said
Marion Nestle, a nutrition professor at New York University.
"That, however, does not make front-page news."
