The
two major reasons people try to avoid eating fat are that they think
fat promotes heart disease and that it makes them fat. Actually, eating
fat does not make people fat, and I’ll tell you why in this
chapter. I’ll discuss the complex relationship between fat and
heart disease in subsequent chapters. It seems intuitive that eating
fat might make you fat, since it is more dense in calories than other
nutrients. However, it is important to remember that these calories
are equal. If you eat 9 calories from carbohydrate you will get just
as much energy as if you eat 9 calories from fat! Your body weight
will be the same whether you eat a low fat diet or a high fat diet,
as long as you consume the same number of calories on either diet.
SO
WHY DO PEOPLE THINK THAT LOW FAT DIETS WILL HELP THEM LOSE WEIGHT?
When people start out on low fat diets, they tend to eat fewer calories,
and may lose weight over the first 2 weeks or so. This might be because
people making an effort to avoid high fat foods fill up on low calorie
foods such as vegetables and grains, and eat fewer calories overall.
A low fat diet can also result in consuming fewer calories over a
week or two if people are tricked, and don’t know that the foods
they are being offered are low in fat and calories, and they choose
servings based on past experience. The opposite is true also; people
can be tricked into eating more calories than usual if they are secretly
fed high calorie foods.
Quite a few studies have tried to show that
this sort of phenomenon can be taken advantage of in real life to
get people to eat fewer calories for long periods of time, and to
achieve long term weight loss. And some studies have shown that during
the first few months that people are given a low fat diet, they may
lose up to about 5 pounds. However, there are also many studies showing
that people don’t lose even 5 pounds on a low fat diet!
Even
for those people who can use a low fat diet to lose a few pounds,
there is a problem with this strategy. The body eventually figures
out what is going on. It adjusts to the lower caloric density of the
foods, the number of calories consumed goes back to normal, and the
body manages to get back to its usual weight. The unfortunate subjects
of these low fat diet studies have usually suffered in vain. Several
studies of a year or so duration have shown that it doesn’t
make much difference whether you eat a diet with the usual 35% of
calories from fat, or drastically reduce calories from fat to 30%,
to 20%, or even to 17%! After a year on low fat diets, together with
lots of advice and counseling and support, subjects generally weigh
about the same as controls who have been left to themselves. By 1
to 2 years on a low fat diet, the lucky ones will weigh at best about
5 pounds less than when they started. More typically, they will be
back to their starting weights.
Other
topics in chapter 1:
WHY
AREN’T REDUCED FAT FOODS A GOOD WAY TO EAT FEWER CALORIES?
THE AMOUNT OF FAT IN THE AMERICAN DIET IS NOT THE REASON SO MANY AMERICANS
ARE OVERWEIGHT!
WHY ARE SUCH DIFFERENT KINDS OF DIETS TOUTED AS BEING THE BEST?
IF WE CAN’T BLAME OBESITY ON FAT IN OUR DIET, WHAT CAN WE BLAME
IT ON?
