We know that over-eating can cause health problems. But what are its
exact implications? Is it too much fat that is causing the increasing weight
problem in our country, or are too many calories the problem regardless
of whether they come from fat?
For some time, we have known that calories are more concentrated in
fat than other food sources. Studies in recent years have also noted that
calories from fat seem to be more easily converted to body fat than calories
from other sources. Studies in which participants increased exercise in
equal amounts, and were allowed to eat as much food as they wanted, found
that those given access solely to low-fat foods lost more weight than subjects
who ate an average diet. Participants only given high-fat foods lost no
weight.
What is not always publicized about such findings is that a low-fat
diet based largely on whole grains, vegetables and fruits contains much
more bulk and tends to be more filling than higher-fat diets. Therefore,
people with free access to low-fat foods tend to not only eat less fat,
but they also tend to consume fewer calories. This relationship between
calories and fat was seen in another recent study that found when calories
were reduced by the same amount, people on low-fat diets didn't lose any
more weight than those on high-fat diets.
These studies seem to suggest that it doesn't matter what you eat, as
long as you control calories. This may be harder to do than you would think.
Research suggests that certain substances in high-fat foods can actually
cause you to overeat.
Subjects in an experiment were given appetizers before lunch that were
equal in portion size and calories. While one day's appetizer was mainly
carbohydrate with a little fat and no alcohol, the second day's starter
was mainly fat with some alcohol and very little carbohydrate. After eating
the appetizer, the participants could eat as much lunch and dinner as they
wanted. Those who ate the high-fat and alcohol appetizer consumed almost
200 calories more at lunch. Even though you might expect that those who
ate more at lunch would compensate by eating less at dinner, the two groups
ate essentially the same number of calories at dinner, giving the high-fat
and alcohol group a higher calorie intake for the day.
So, not only do high-fat foods have more calories in smaller portions,
this experiment suggests that they (at least in conjunction with alcohol)
can also lead to even greater caloric intake by interfering with the body's
normal food control mechanisms. In studies when too many calories are eaten
as carbohydrates, subjects tend to eat less later to compensate; when excess
calories are eaten as fat, however, subjects seem less likely to limit
subsequent food intake.
Because all the information is not in, the question of fat versus calories
is not a simple one. An excess of either fat or calories will promote weight
gain and raise cancer risk. Therefore, a healthy diet should include both.
By eating fat-free foods in moderation, as well as foods that have fewer
calories but still have fat, you can follow the dietary guidelines recommended
by experts like the American Institute for Cancer Research to maintain
a healthy weight and lower cancer risk.
For a free brochure on calories, exercise and cancer risk, send a self-addressed,
stamped envelope to AICR, Dept. TLE, Washington, DC 20069.
