Q: I eat red meat, mostly mutton and beef, at least four to five times a week. Is this healthy for me?

KS, Calcutta.

Red meat has plenty of good quality protein but it also contains a large amount of fat, mostly in the form of saturated fatty acids. It is this high saturated-fat content that makes red meat unhealthy. Furthermore, processing of meat involves addition of chemicals, and its cooking can result in production of various other chemicals. Both these types of chemicals can be detrimental to our health. Finally, the protein in the red meat after being digested is absorbed into the blood and metabolised by the body. The by-products of this protein metabolism can also have adverse health implications. Let’s explore deeper:

• The high saturated-fat content of red meat increases the blood cholesterol levels, including the bad LDL variety that clog up the arteries causing heart attacks and cerebral strokes. This clogging is further aided by the high iron content of meat. Iron acts as an oxidant — oxidising the cholesterol. Oxidised cholesterol gets more easily deposited inside our arteries compared to non-oxidised cholesterol.

• Meat contains the fatty acid ‘arachidonic acid’. This helps our body produce more of the pro-inflammatory, hormone-like chemicals called prostaglandins, which have the potential of aggravating inflammatory illnesses like arthritis, asthma, etc. (Using garlic, ginger and onions to cook meat can reduce this inflammatory response as these foods have anti-inflammatory properties.)

• Meat, when cooked at high temperature, like in frying, grilling, barbecueing (tandoori) or pressure cooking, produces heterocyclic aromatic amines (HAA) — chemicals that can cause cancer, particularly pancreatic cancer. This effect can be made worse if vegetable oils like sunflower oil or corn oil is used to cook the meat. Low-temperature cooking of meat, like stewing, boiling or microwaving, does not produce HAAs.

• Sodium nitrite used as a preservative in cured meats, such as bacon, salami, ham, etc., can get converted in the body into nitrosamines — chemicals that can again cause cancer, especially in the stomach and pancreas. Vitamin C can block the formation of nitrosamines in the body.

• Metabolic breakdown of protein in red meat produces a toxic amino acid called homocysteine. This can injure and damage the inner lining of the arteries, predisposing them to atherosclerosis and clogging and leading to heart attacks. Homocysteine levels are also elevated by lack of exercise, smoking and excessive coffee consumption. Its increase in the blood can be prevented by intake of folic acid — found in abundance in green leafy vegetables — as also by the intake of vitamins B6 and B12.

Recommendation: Eat red meat no more than twice a month. Cook it at low temperature using oils like olive, rapeseed, mustard or groundnut. Avoid cured meats. Eat plenty of green leafy vegetables and fruits. Substitute red meat with fish and chicken.