All you need to know about cholesterol

Cholesterol is the one nutrient looked at with great suspicion by common man. Without realising the role of cholesterol in our well being, we often consider it a useless toxic product present in our food. This may be due to excessive highlighting of the ill-effects of cholesterol without mention of its usefulness. Cholesterol is present in small amounts in almost all body tissues and constitutes an important fraction of the blood lipoproteins. It is also required for the production of hormones.

What is cholesterol

The word sterol literally means “solid alcohol.” Since cholesterol was first isolated from gall stones it got this name meaning “solid alcohol from bile.” Cholesterol is a lipid of animal origin. The liver meets body needs of cholesterol regardless of its dietary intake. Low density lipoprotein intake facilitates the synthesis of cholesterol.

Cholesterol concentration is high in the liver, the adrenal, and the white and grey matter of the brain and the peripheral nerves. Cholesterol is a component of cell membranes and furnishes the molecules for the synthesis of provitamin D, adrenocortical hormones like different type steroids, sex hormones, and bile salts. Our body cannot function normally without this lipid compound.

Heredity, diet and obesity are other important factors for high cholesterol. Nothing much can be done about the heredity factor, but a substantial reduction in your blood cholesterol level can be achieved safely through dietary modifications. There are food items that lower cholesterol level and others, which increase serum cholesterol level. A high level of blood cholesterol is a major risk factor of coronary heart disease and artherosclerosis. It also increases in patients with obesity, cirrhosis, gall bladder stones, hypothyroidism, nephrotic syndrome, diabetes and some types of metabolic diseases.

Sources of cholesterol

The sources of cholesterol are:

  1. Endogenous synthesis from acetate by the liver and the intestines particularly the ileum.
  2. Exogenous from food.
Endogenous cholesterol

The endogenous synthesis of cholesterol is partly regulated by the dietary cholesterol intake. Even on cholesterol free diet, the body for its need, cholesterol will be synthesised in the liver. The cholesterol absorption capacity of the intestines is limited to only 300 – 500 mg per day. Cholesterol synthesis is about 1.5 – 2 gm daily, which is about 3 – 6 times that consumed in food.

Rich sources and foods that raise cholesterol

Butter, cheese, cream, egg yolk, kidney, liver, red meat, brain, biscuits, cakes, chocolates and pastries.

Poor sources and foods that lower cholesterol.

Egg white, fish, all unsaturated vegetables oils, skim milk, all vegetables, all fruits, whole meal bread, oats, cereals are poor source of cholesterol.

How does the diet help?

Saturated fatty acids are found to increase blood cholesterol, whereas unsaturated fatty acids are found to decrease it. Cholesterol is found in the body even when the diet contains no cholesterol. Foods that contain cholesterol such as egg yolk, mutton, organ meat, prawns, lobsters etc, and saturated fatty acids are found to increase serum cholesterol levels.

Foods rich in cellulose and pectin, mainly fruits and vegetables, are found to reduce serum cholesterol levels by preventing its absorption from the intestine. Turmeric contains a factor responsible for decreasing serum cholesterol levels. Onions, garlic, and bengal gram are believed to lower serum cholesterol levels but this is controversial. Foods containing soluble fibre such as oat meal, wheat bran, citrus fruits and beans dissolve in water and can flush out cholesterol.

Cholesterol levels

In adults, 150 – 200mg/dl of cholesterol is considered as normal range. The level between 200 – 250 mg/dl of cholesterol is considered suspected or borderline range. Whereas, above 250 mg/dl is considered as high and requires dietary or medical management.

Points to note

  1. Eat a variety of foods.
  2. Avoid too much saturated fat and cholesterol like butter, cheese, cream, egg yolk, kidney, liver, organ meats, red meat, brain, biscuits, cakes, chocolates and pastries.
  3. Eat foods with adequate fibre like all vegetables, all fruits, whole meal bread, oats, and cereals.
  4. Avoid too much sugar.
  5. Avoid too much salt.
  6. If you drink alcohol, do so in moderation.

Cholesterol content of foods

Food contents Cholesterol mg/100gm Food contents Cholesterol mg/100gm
Butter 280 Ghee 310
Cream processed 140 Whole milk fresh 11
Skimmed milk fresh 0.4 Egg hen whole 498
Egg yolk 1330 Egg white 0
Duck 70 Lamb 70
Pork 110 Lamb liver 610
Brain 2000 Heart 150
Kidney 375 Crab 145
Lobster 200 Shrimps 150
Oysters 200 Cod 50
Mackerel 80 Sardine 70
Lard and animal fats 95

Image: Flickr/creativecommons ariztravel