Apr. 10, 2001 (Environmental News Network) - If dietary fat were a cartoon villain, it would probably be portrayed as a towering, virtually unstoppable monster. But is it a villain of our own creation?
For years, North Americans have waged a war on fat in our food. Guided by
government recommendations, media stories and popular diets, we've been
conscientiously watching our fat consumption. A low-fat diet, we have been
told, is the cornerstone to a healthy heart and body.
As a result, since the mid-1980s the words "low fat" and "fat free" began
to appear on just about every food product imaginable. An entire industry
developed around producing low-fat snack foods, and consumers have gobbled
them up in the hope of losing weight and improving health.
At the same time, more men and women have been dragging themselves to the
gym to burn off extra fat, while others have turned to surgery and drugs in
attempts to lose weight and appear younger and healthier. It's a booming
business.
Just last week, researchers writing in the journal Science reported that
they've bred mice with a gene removed, a procedure that appears to inhibit the
accumulation of body fat. The researchers say they hope to produce a drug that
would suppress the gene in humans, enabling people to eat more without gaining
weight.
Obesity is indeed a huge problem in North America. It shortens lives,
increases the likelihood of illnesses such as diabetes and heart disease, and
creates a terrible burden on health care -- an annual price tag of $110
billion in the United States alone, according to the Harvard School of Public
Health.
On the surface, it appears we're winning the war on fat. Dietary fat
consumption has actually dropped from more than 40 percent of our total
calories 30 years ago to 34 percent today.
So why aren't we getting thinner? Obesity rates in the United States
remained relatively constant between 1960 and 1980. But since then, as dietary
fat consumption has decreased, obesity rates have jumped from 14 percent to
more than 22 percent.
Today, more than half of all Americans are now considered overweight, and
Canadians aren't far behind. Meanwhile, the incidence of heart disease, which
a low-fat diet was originally thought to reduce, has yet to drop.
In fact, according to an article in last week's Science, there is
actually very little scientific basis for our demonization of dietary fat.
Decades of research and hundreds of millions of dollars have failed to prove
that eating less fat will make us live longer. Recent data on heart disease
trends in Europe suggest that eating fresh vegetables year-round is more
important to health than is the amount of fat we eat. Even saturated fat,
often regarded as the worst culprit in heart disease, has beneficial and
negative health effects.
One of the reasons why our reduced fat diets are not reducing obesity is
that we haven't been eating less overall, just less fat. Instead, we've
switched to highly processed, carbohydrate-rich foods which could actually be
making things worse because they can induce a hormonal change that stimulates
hunger and promotes overeating.
A sedentary lifestyle punctuated by weekly workouts at the gym may not be
the best way to reduce obesity either. A study published last week in the
journal Nature found that the best way to increase metabolic rate (the rate at
which our bodies burn calories) is through frequent, moderate levels of
exercise such as walking, rather than less frequent bouts of intense exercise.
Oh, and those genetically engineered, gluttonous mice? Although they
appear normal, researchers caution that they also run a consistently higher
body temperature, which may not be healthy for them in the long term. In other
words, there appears to be no quick fix to our weight woes. And there doesn't
appear to be a clear-cut villain, either.
