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Fats and oils are essential elements
in any healthful diet. Fats do more than supply some important nutrients.
They also make foods feel and taste rich and satisfying. They signal the
stomach that enough food has been eaten, giving people the feeling of
satiety that encourages them to stop eating before they overeat. Fats are
found in some foods, notably meats, poultry, fish, cheeses, eggs, and nuts.
The type of fats a food contains may be monounsaturated, polyunsaturated,
or saturated. Each appears to have a different effect on the body.
Monounsaturated Fats
When findings about the Mediterranean
diet were released, it seemed clear that the use of olive oil in those
diets played a role in a generally lower incidence of cardiovascular
disease. Monounsaturated fats have a tendency to lower the levels of
certain types of cholesterol in the blood and raise others. The net result
of this is that diets that rely upon monounsaturated fats, rather than
saturated fats, are likely to encourage low levels of serum cholesterol.
This means that the chances of developing atherosclerosis are reduced.
Nuts and olives, as well as oils made from those foods, contain primarily
monounsaturated oils.
Polyunsaturated Fats
Oils made from corn, safflower, and
rapeseed (canola), and other vegetable sources are referred to as
polyunsaturated. While these oils are still preferred over saturated fats
in a healthful diet, they do not appear to have precisely the same
benefits as monounsaturated fats. Vegetable oils are frequently used to
prepare shortening and margarine. This process, known as hydrogenation,
changes the overall structure of the fat. Instead of pouring at room
temperature, these hydrogenated oils become "plastic", or solid at room
temperature.
Saturated Fats
Saturated fats are found typically in
animal foods including butter, marbling in meats, lard, chicken skin,
bacon, sausages and eggs. The so called "tropical oils" are also saturated
fats. Examples like coconut and palm oils. Saturated fats have been linked
to increase levels of serum cholesterol and an increased risk of
developing cardio-vascular diseases.
Cholesterol
This is a type of fatty acid found in
animal foods. There is a distinction between dietary cholesterol and serum
cholesterol. Dietary cholesterol is that which is found in the foods
themselves. Serum cholesterol is found in your bloodstream. When you have
a blood test done to determine your personal cholesterol levels, the
doctor will review specific components found in the blood, known as
lipoproteins. Low-density lipoproteins (LDL) are associated with an
increased risk of developing arteriosclerosis. High-density lipoproteins (HDL)
appear to reduce the risk, since HDL actually removes LDL from your blood.
Certain individuals are more sensitive
to dietary cholesterol than others. Learning how to reduce the amount of
foods containing cholesterol in your diet is critical if you are one of
those individuals. But, it may not always be enough. Your body produces
cholesterol on its own, whether or not you eat foods containing it.
Plant-based foods, even those high in fats and oils, do not contain
cholesterol. This means that peanut butter, almonds, olives, beans and
sesame seeds are all "cholesterol free".
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