What is cholesterol?
Cholesterol is not all bad. It is a wax-like fatty substance (called lipids) made by the liver to assist in the process of digestion, the secretion of hormones, the production of vitamin D, and the production of healthy cells. It aids the inefficient function of the brain and other organs of the body. The body produces all the cholesterol it needs. It can move in the blood only with the aid of proteins (called lipoproteins), as well as stored in the cells too.
However, too much fat in the diet can raise the body’s cholesterol levels, and it gradually begins to stick to the walls of the arteries and blood vessels, causing plaque to build up, thereby narrowing and hardening them (called atherosclerosis), leading to restricted blood flow and blockage. This puts pressure on the heart to pump blood harder and can lead to extreme risk of angina, coronary heart disease, stroke, heart attack, carotid heart disease, peripheral arterial disease, among other health risks.
There are 3 types of lipoproteins which are a combination of fats and proteins:
- HDL or high density cholesterol: it is the ‘good’ cholesterol and carries cholesterol from the body’s organs back to the liver.
- LDL cholesterol or low density cholesterol: it is the ‘bad’ cholesterol and high levels of LDL indicate the risk of plaque- build up in the arteries.
- VLDL or very low density cholesterol: it carries triglycerides in the blood. High levels of VLDL are also bad and contribute to plaque build-up in the arteries.
Around 30% of the urban population and 20% of the rural population in India have high cholesterol levels or hypercholesterolemia.
Causes & Risk factors
- Heredity: The tendency for high cholesterol levels can be inherited and runs in families (called familial hypercholesterolemia or FH).
- Unhealthy high-fat diet: All cholesterol sourced from food comes from animal products.A diet rich in saturated fats and trans fats (too much intake of butter, ghee, dairy products, meats, chocolate, fast food, deep fried and processed foods) not only leads to high LDL levels, weight gain but also poor nutrition over all.
- Sedentary lifestyle and low physical activity: Lack of enough exercise and long hours of sitting lowers HDL levels.
- Obesity: Being overweight leads to excessive deposition of fat in the body’s cells and raises cholesterol levels.
- Smoking: Smoking lowers HDL levels in the body and raises the LDL levels, especially among women.
- Alcohol: Excessive drinking raises cholesterol and triglyceride levels.
- Ethnicity: Some races are more prone to higher cholesterol levels (e.g. African Americans).
- Age: Cholesterol levels begin to build up as one grows older. Even young adults and teenagers can have raised cholesterol levels, which can lead to heart diseases by the time they reach middle age.
- Post-menopausal women have shown a tendency to have lower HDL levels and higher LDL levels.
- Certain medicines: Certain medicines can also raise LDL levels (e.g. medicines for cancer treatment, hypertension, diabetes, HIV/AIDS, and medicines like diuretics, beta-blockers, anti-convulsants, corticosteroids and growth hormones, etc.).
- Those suffering from diseases such as diabetes, kidney disease, Lupus, hypothyroidism, HIV/AIDS and cancer may have poor and unhealthy cholesterol levels.
A blood test (called lipid profile) is the only way to measure cholesterol levels, as there are no outward symptoms.
Fasting for 9-12 hours is required to prepare for this test to get accurate results.
A sample of blood is drawn from a vein in the inside elbow area of the arm.
The lipid profile test measures the following levels in the blood:
- Total cholesterol
- HDL-LDL ratio
Recommended cholesterol levels as per age
Doctors recommend that screening for cholesterol should begin early, by the age of 9-11 years, and be repeated every 5 years. For people above 20 years, screening is a must every 1-2 years.
Given below are optimal cholesterol levels by age:
Optimal levels for men & women below 19 years:
Total cholesterol: >170 mg/dL
Optimal levels for men & women over 20 years of age:
Total cholesterol: 125-200 mg/dL
HDL: < 45 mg/dL
LDL: > 100 mg/dL (for women it should be > 50 mg/dL)
Preventive steps to tackle hypercholesterolemia
- Balanced, low fat diet with plenty of fresh green vegetables, fruits and multigrains.
- Physical exercise for at least 30-45 minutes per day.
- Lose the extra weight, if overweight or obese.
- Quit smoking.
- Cut down on mental stress.
- People with other co-existing diseases like high blood pressure and/or diabetes may additionally need medication to keep cholesterol levels under control.