|
Facts
about Fats
Is
fat essential?
Why
too much fat is harmful?
Western Diseases
Different kinds of fats - saturated and unsaturated
Animal
or vegetable fats?
Which Fat
Cholesterol
How to lower your Cholesterol Level
Triglycerides
Fish Fats
Facts
about Fats
Almost
everyone thinks previous generations ate much more fat with breakfasts
of fried eggs and roast dinners followed by apple pie and cream. In
fact, people in most countries today eat more fat than their
predecessors, the major difference being that it is now concealed in
fast foods, processed and take-away items.
(Return)
Is
fat essential?
Babies
begin life drinking breast or formula milks in which 50 per cent of
the kilojoules come from fat. This is important for a baby’s rapid
growth, and, for the first few years of life, dietary fat continues
to be an important source of energy. Gradually the need for fat
however decreases.
Everyone
needs some essential fatty acids. You won’t find these in fatty
meats, pastries, chips or most fried foods. Essential fatty acids are
in many foods without any obvious fat. Rabbit, turkey, chicken, fish,
rolled oats, wheat-germ, egg yolk, nuts, seeds and vegetables are all
sources of the essential fatty acids needed by brain and nerve cells
and to keep the membranes around all body cells healthy. Many
vegetable oils also contain essential fatty acids.
(Return)
Why
too much fat is harmful?
A high fat diet is linked with excess
weight, coronary heart disease and high blood pressure, diabetes,
gallstones and some cancers. At 37 kilojoules/gram, fats have more
than twice as many kilojoules as protein (17 kJ/g) or carbohydrates
(16 kJ/g). Only alcohol, with 29 kJ/g comes close to fat in
kilojoules.
To
damn fat further, researchers have now shown that the body
preferentially uses carbohydrates for energy and more easily converts
fats in food into body fat. High levels of body fat then further
increase the risks for all the conditions listed above.
(Return)
Western
Diseases
In
countries where the diet is low in fat, there is a very small incidence
of “Western diseases”. However, when people migrate, they pick up
the host country’s pattern of disease. When Japanese people move to
the United States, they develop problems associated with a high fat
diet such as heart disease, diabetes, gallstones, and cancers of the
breast and bowel.
Eating
saturated fat can cause the body to make too much cholesterol. This
occurs more in some people than in others.
Excess
dietary fat also increases the load on the heart so it must pump much
harder. This can cause blood pressure to rise. Saturated fats create
the greatest risk for high blood pressure. Saturated fats are also a
risk factor in maturity-onset diabetes. For gallstones, all fats are
a problem. In certain cancers, too much of any kind of fat except for
fish fats, and monounsaturated fat present in olive oil - is a
potential problem.
(Return)
Different
kinds of fats - saturated and unsaturated
"Saturated","monounsaturated" and
"polyunsaturated" refer to the chemical
structure of fats. Foods always contain a mixture of many different
fats but one type usually predominates. For example,
margarine which is labeled ‘polyunsaturated’ may have 45
per cent of its fat in the form of polyunsaturated fat, 35 per cent as
monounsaturated fat and 20 per cent as saturated fat. Even
polyunsaturated margarines thus contribute some saturated fat to the
diet - a point that often escapes notice.
Some
types of fat create more health problems than others. People living in
Mediterranean countries eat a lot of olive oil but have long life
expectancy with low levels of heart disease and cancer. Traditional
Eskimos also had very low levels of heart disease, diabetes or other
health problems, even though their diet was high in fat. Their secret
lay in fish fats. The high content of saturated fats in a typical diet
seems to be responsible for many of our diet-related health problems.
(Return)
Animal
or vegetable fats?
Saturated
fats are not synonymous with animal fats. Some animal fats, such as
those in fish and game meats (like venison) are mainly unsaturated. On
the other hand, many vegetable fats, such as those found in chocolate,
some margarines, coconut and palm kernel oils are highly saturated
fats. When a food product lists ‘vegetable oil’ on its label, the
ingredient is often palm kernel oil -a highly saturated fat.
Some
saturated fats affect blood cholesterol more than others. Claims are
sometimes made that chocolate contains stearic acid. This is a
saturated fat that does not seem to raise cholesterol. However,
chocolate is also one of the richest sources of palmitic acid - a
saturated fat that does indeed raise blood cholesterol levels.
(Return)
|
