(By Dr. Paul Nanna)
The heart starts beating at about the eighth week of pregnancy, and continues to do so throughout an individual’s life. The heart cannot afford to fail in its function of pumping blood to the whole body. In performing this function, the heart also ensures that adequate blood is pumped into itself.
The arteries that pump blood to the heart are known as the coronary arteries. Blockage or narrowing of these vessels can lead to what is known as coronary heart disease. As this narrowing increases, a left-sided chest pain, known as angina, will set in, due to a reduction in blood, oxygen and nutrient supply to the heart.
Total blockage of a coronary artery that supplies a section of the heart causes death of that portion of the heart, giving rise to what is known as heart attack. The commonest cause of narrowing of the coronary artery is artherosclerosis. Artherosclerosis is the buildup of cholesterol and fatty deposits, known as plaques, on the inner wall of the artery.
There are certain risk factors associated with coronary heart disease and they include: dehydration, family history, excessive alcohol consumption, smoking, stress, lack of exercise, hyperlipidemia and obesity.
More than a risk factor, long-standing dehydration can be considered a cause of artherosclerosis. In my article on the management of hypertension, I explained how dehydration causes the brain to send signals to the liver to begin to produce more cholesterol, which come into use when the body goes into a rationing mode as a result of dehydration.
In a state of dehydration, water is redistributed from the muscles, bones and joints to the brain, heart, lungs, liver and kidneys – the five vital organs in the body. Cholesterol will have to be deposited between the cells in the walls of the capillaries, to take over the usual adhesive function of water between the cells. Cholesterol, being impermeable to water, drastically reduces the passage of water out of the blood in the capillaries into the muscles. These cholesterol deposits initially found between the cells will eventually begin to grow into the lumen of the capillaries, where they join together to form plaques. At this time also, the blood level of cholesterol is very high and such hypercholesterolemia can easily be managed by increasing one’s daily consumption of water and sustaining it there.
Principles of prevention
There are fundamental principles to observe in preventing coronary heart disease.
The first principle is to drink sufficient water on a daily basis. I will not belabour this principle because I believe that a lot of the readers of this column now practise it.
Next is exercise. The heart benefits a lot through regular exercise. Through exercise, the heart becomes strengthened and the resting pressure at which the heart pumps blood is reduced, translating into a lower blood pressure. Moreover, cholesterol and blood sugar levels are reduced, thus preventing heart disease. Exercise also helps to create new capillaries for supply of blood and opens up blocked ones. This will further cause a reduction of the blood pressure and eliminate the risk of heart disease.
Added to the above is diet. What you eat plays a very significant role in ensuring the good health of the heart. To begin with, whatever you eat must not be excessive. Do not overeat. You will have to eat more of some food, reduce some and avoid others entirely, to keep your heart healthy throughout your life. To keep your heart healthy, you have to eat more of the low-calorie, nutrient-rich foods like fresh, raw vegetables and fruits. They are rich sources of vitamins, minerals, fibre and substances that directly prevent heart disease. Whole grains, like whole wheat and oats, brown rice, barley and ground flaxseed, are also high in fibre, minerals and vitamins.
Also recommended to keep the heart healthy are low-fat proteins found in foods like skimmed milk, low-fat yoghurt, egg white and cold water fish, such as tuna and salmon. Others are skinless poultry, legumes (kidney and black beans, lentils, soybeans), tofu and lean meat.
Still on diet, to ensure that the heart is healthy, high-calorie, high-sodium foods like fast foods, processed and refined foods should be avoided. These include white flour products, such as white bread and cakes, pastries, pasta etc; white sugar, table salt and white rice. Others are unhealthy fats like saturated, hydrogenated and trans fats, such as is in margarine, butter, shortening etc.
Finally, as part of the principles of preventing coronary heart disease, you need to take different varieties of the food that you are allowed to take. These may include things that you have not been used to eating. Doing this ensures that your heart gets all that it needs to stay healthy from different sources and also makes eating less boring for you.