What is Cholesterol?
Cholesterol is a fatty substance found in the liver, brain, nervous system and blood, and manufactured by all cells but mainly by the liver and intestine. It is essential for the normal daily activities of our cells, as well as for the manufacture of vitamin D and some hormones. The body is able to produce all that it requires even if none is eaten in the diet, but both dietary consumption and fasting reduce the amount made by the body, and consumption of large amounts of animal fat increases the amount.
Cholesterol is not soluble in blood, and so it is carried around the body in the bloodstream as lipoproteins, which are measured in a blood profile called the lipogram:
Serum cholesterol measures the total cholesterol level including that being transported. A high level is called hypercholesterolemia. The level should be less than 5.2mmol/l, but is allowed to rise with age.
Low Density Lipoproteins (LDLs ) carry large amounts of cholesterol from the liver to the cells. If there is too much it will tend to stick to the walls of the blood vessels, resulting in atherosclerosis. Thus raised levels of LDLS are less healthy.
High Density Lipoproteins (HDLs) carry cholesterol back to the liver from the other organs for breakdown and excretion. Thus HDLS are ‘HEALTHY’.
The ideal ratio of HDL:Chol is>25%
Triglycerides are a form of fat being transported in the blood.
What causes a high cholesterol level?
- Genetics-family, ethnic, and racial background.
- Age-levels increase gradually after 20 years of age.
- Hormones-women tend to have better profiles with higher HDL than men until the menopause, when they catch up.
- Diet-excess refined sugars, animal fats, and kilojoules all increase cholesterol levels.
- Being overweight tends to increase LDL and decrease HDL.
- Exercise-lack of activity increases LDL, and vice versa.
- Smoking inhibits the manufacture of substances that break down cholesterol.
- Stress-severe stress causes fat to be released into the bloodstream, increasing triglycerides, LDL and total cholesterol.
- Alcohol-in excess increases LDL and the triglycerides, although limited amounts may raise the HDL.
- Thyroid problems. An over- or underactive thyroid will adversely affect the lipid profile.
- Uncontrolled diabetes will result in raised triglycerides
Does it matter?
While raised serum cholesterol has been shown to increase the incidence of heart disease, it is only a part of the picture. Several other lifestyle factors also need to be taken into account when assessing a person’s risk of heart disease, including family history, gender, weight, exercise habits, smoking habits, and diet. A more complete picture is obtained by looking at the whole lipogram, which includes the HDL, LDL and triglycerides. The ratio of cholesterol to HDL is important with the ideal ratio of HDL: Chol being >25%.
What about children with a raised cholesterol?
While some of these children will have a genetic form of hypercholesterolemia, in recent years the increase in junk food and sugar in children’s’ diets means that many are diet related. If it is genetic, this means that there may be a family history of heart disease occurring in the 30’s, or even 20’s, and the implications are most serious for the parents, as they are at short-term risk; while the child has several years ‘in hand’ to control his lipids, so alerting the parents may be life saving! Thus, any minor with raised cholesterol should consult their GP, who should test the parents, if it has not already been done.
What is the usual treatment?
The medication used will depend on the precise abnormality, as there are different agents for lowering cholesterol, triglycerides, and combined problems.
- Any physical ailments such as hypothyroidism, diabetes and blood pressure should be screened for and controlled.
- weight control and diet change are the first line of attack.
- If the serum cholesterol does not respond to dietary management after 3 months, the client will be evaluated as to the need for cholesterol lowering medication.
- The newest, and most expensive medicines are the ‘Statins’.
- The ‘Fibrates’ are less potent, have a few side effects, and are suitable for children.
- Nicotinic acid is cheap and effective, but can cause flushing; there is a non flush variety available.
- Probucol (Lurselle) is also in common use and is effective.
- Colestyramine (Questran) interferes with bile and fat absorption but is very unpleasant to take.
- The GP will take into account the patient’s age, sex, family history, medical background, and other risk factors such as smoking, exercise, stress levels etc.
If dietary management is successful, where to next?
Once the cholesterol has been successfully reduced to normal by diet, it is up to the patient, to maintain it!
He or she must realise that their previous habits were harmful, and their future health depends on changing those habits. Please see ‘Guidelines for a healthy diet’.
- Red meat should not be eaten more than 2-3 times per week and fish should be eaten at least twice weekly.
- People with raised LDL or low HDL, with a normal cholesterol, should be encouraged to use polyunsaturated fats such as grape seed, olive, peanut or canola oil, to eat plenty of unrefined carbohydrates.
- Regular exercise is an important aspect of a healthy lifestyle.
Why did my cholesterol level go up instead of down?
- If the specimen was taken after a meal, there may be a small rise.
- A high alcohol intake.
- Recent change in hormone therapy e.g. beginning the oral contraceptive pill.
- Gall stones.
- Recent onset of Diabetes, or poor diabetic control.
- Recent onset of certain kinds of kidney disorder.
- An underactive thyroid.
WHAT OTHER TREATMENTS ARE AVAILABLE?
- Nutritional management : Avoid refined sugars in any form. This includes fruit juice, ‘gas ‘cool drinks, sugar, white flour etc. Instead eat beans, lentils and peas and fibre rich fruit and vegetables, which are beneficial, especially oats, and drink water! See the separate advice sheet on a healthy diet. Diet alone may reduce the incidence of atherosclerosis by 50- 70%.
- Exercise regularly: at least 30 minutes fast walking (until you are slightly out of breath) 3 times weekly to begin.
- Increase your intake of Ω3 oils by eating oily fish and nuts, and take 1000mg omega 3 oil supplement daily.
- Limit saturated (animal) fats to less than3% of total calories per day. These are usually the fats that are hard if kept in the fridge. Mono unsaturated fats e.g. grape seed, olive, peanut, and canola oils should make up the highest proportion of the daily fat intake, which should not exceed 30% of our total daily calorie intake, with polyunsaturated fats e.g. Sesame, sunflower, maize and soybean oils less than 10% of the total calories per day. Note that a too low fat intake (less than 10%) lowers the HDL as well as LDL.
- Choline, vitamin B12, biotin, lecithin, and inositol all help prevent accumulation of fat in the liver, and vitamins C and E are useful in preventing deposition of cholesterol, so find a good antioxidant vitamin and mineral supplement , and take lecithin and inositol supplements.
- Chromium raises the HDL level.
- Avoid smoking and drinking alcohol excessively .
- Use filtered coffee instead of percolated. Decaffeinated coffee actually raises the cholesterol due to the stronger beans used in its manufacture.
- TRY TO EAT FOODS THAT GROW IN THE GROUND or LIVE IN WATER, RATHER THAN FOODS THAT HAVE BEEN PROCESSED THROUGH A FACTORY.
- If you are a man, or a woman who is in menopause you should check your iron levels, as elevated levels of iron can cause major oxidative damage in the blood vessels, heart and other organs. Excess iron is also one of the major contributing factors of cancer risk.