Heather Little-White, Contributor

Onions play a role in flavouring your foods, but beyond that they provide several nutritional and therapeutic benefits to the body. Onions have moderate amounts of protein, fat, fibre and good amounts of calcium, phosphorus and potassium. Even the stalk is edible, and it contains good amounts of carotene and iron.

The age-old practice of onions in soup, raw, roasted or cooked into a syrup, is still commonly used to cure the common cold. As a relative of garlic, onion has been cultivated for more than 6,000 years and has been used to cure many ailments. Onions have been used to treat infections in particular and as a diuretic to reduce blood pressure, aid congestion, as a heart tonic and as an aphrodisiac.

Heart healthy

Onions can boost your good high-density lipoproteins (HDLs) blood cholesterol by an average of 30 per cent. The effectiveness of onions in treating disease or maintaining good health is because of their therapeutic compounds. Dr Victor Gurewich of Tufts University discovered that raw, strong onions had a positive effect on his heart patients. A typical therapeutic course includes half a medium-size onion and freshly squeezed orange course. This is enough to raise the good cholesterol in the body.

It is raw onions that present the greatest capacity to heal; cooking reduces or destroys the potency. However, cooked onions are good for the cardiovascular system in other ways. Onions act as an anticoagulant and boost the body's blood-clotting system, heightening the blood's tendency to dissolve clots and prevent blood cells from sticking together to form clots. Where dietary fat had pushed up blood cholesterol, onions bring the cholesterol levels back down.

Blood pressure

Onion eaters show better signs of cardiovascular health. An extensive survey in India indicated that onion and garlic lovers had better profiles of blood constituents - cholesterol, triglycerides and HDLs compared to persons who ate very little onion and garlic. The best blood was found among persons eating about three to four cups of raw onions each week. Researchers believe that even a cup of raw onions per week will keep the blood in better shape and prevent heart disease. Onions also lowers blood pressure through a compound known as prostaglandin.

In addition to boosting cardiovascular health, there several other benefits to be gained by eating onions:

Diabetics will be happy to learn that onions were used to treat diabetes in ancient times because of blood sugar reducers found in onions. Indian researchers found that onion extracts reduced blood-sugar levels of humans after they had been given glucose. Pharmacists in Egypt are working on an experiment with rabbits aimed at isolating a compound, diphenylamine, from onions to lower blood sugar.

Urinary disorders: Onions are beneficial in the treatment of urinary disorders. Treat a burning sensation while passing urine by boiling 100 grams of onion in 600ml of water. Consume when the volume reduces to half. If onion and sugar mixture is taken, it gives good relief for retaining urine.

Antibiotic: Louis Pasteur gave the nod of approval to onion as an antibiotic. Onion and its essences are known for the antibacterial properties which can kill a range of disease-causing bacteria, including E. coli and Salmonella. It is recommended that chewing raw onions for three to eight minutes to sterilise the lining of the mouth.

Tuberculosis: The potency of onions has killed strains of tuberculosis.

Colds and coughs: It is suggested that eating raw onions might have a curative effect on sore throat resulting from a cold. Onions are known as a good remedy for colds and coughs, as they induce the stomach to release substances in the throat and lungs to break up mucus congestion. Onions have formed the base of some expectorants which push mucus through the lungs to the throat where it is coughed up. Onions help with bad coughs and bronchitis.

Cancer: Sulphur compounds present in onion will help to prevent the growth of cancer cells. Researchers at the M.D. Anderson Hospital and Tumor Institute isolated polysulfide in onions as blocking enzymes needed to activate potent cancer-causing substances. The Harvard School of Dentistry also found that onion extract placed on cultures of oral cancer cells in animals significantly inhibited or destroyed the growth of cancer cells. The National Cancer Institute in the United States is exploring the use of sulphides as a cancer chemo-preventative agent.

Piles: Onions are also used in the treatment of anaemia, bleeding piles and teeth disorders.

Headaches: Crushed raw onion can be applied on the forehead to get relief from headaches.

Onion is a versatile kitchen herb that adds spice to the foods you prepare as well as providing nutritional and therapeutic benefits.

Heather Little-White, PhD, is a nutrition and lifestyle consultant in Kingston. Send comments to editor@gleanerjm.com or fax 922-6223.