Red meat includes fresh beef, pork, lamb, mutton and veal, as well as processed meats that come from these animal sources. These foods can add value to your diet, as they are rich in protein, iron, B vitamins and zinc. However, their saturated fat and cholesterol content can adversely affect your health, and the manner in which red meat is produced, processed and cooked can also impact your well-being. For these reasons, limiting your intake of this type of meat can improve your overall health and lower your risk of developing disease.
Animal-based dietary fats, such as the ones found in red meat, can contribute to risk factors associated with heart disease and stroke. They add cholesterol and saturated fats to your diet, which can increase the accumulation of a fatty substance called plaque to the walls lining your arteries. In this condition, known as atherosclerosis, your heart works harder to pump blood through the narrowed blood vessels, increasing your chance of heart attack. The fats in red meat can also cause you to put on extra weight, a risk factor for developing high blood pressure, which is also a risk factor for cardiovascular disease.
Red meat can increase your likelihood of developing cancer in several ways. For example, the iron in red meat is contained in a protein called heme, and this protein can easily undergo a chemical change in your gut to form carcinogenic N-nitroso compounds associated with, for instance, colorectal cancer. The fat content of red meat might be a contributing factor in the incidence of estrogen- and progesterone-sensitive breast cancer, and, in addition, hormones used in the production of red meat can exhibit estrogenic activity and might also boost your breast cancer risk.
The greater the amount of red meat you consume, and of processed red meat in particular, the greater your risk can be of developing type 2 diabetes. Processed red meats can contain preservatives such as nitrosoamines that are toxic to the pancreatic cells that produce insulin. In addition, chemical changes to red meat during cooking or processing can lead to insulin resistance in your cells and tissues. Although the relationship between the saturated fats in red meat and type 2 diabetes onset is unclear, the cholesterol content of these foods is associated with an increased risk of developing the disease.
Cooking methods for red meat – and for poultry and fish as well – can affect the health risks associated with consuming animal proteins. Pan-frying at high heat or grilling over an open flame can cause the amino acids, creatine and sugar in red meat to form heterocyclic amines, compounds that can cause gene mutations. Polycyclic aromatic hydrocarbons can form when fats and liquid from red meat drip onto open flames and then adhere to the meat as the flames return to the food surface. Both these chemicals might alter the structure of your DNA and potentially increase your cancer risk. Cooking red meat over low heat and avoiding grilled red meat can help limit your intake of heterocyclic amines and polycyclic aromatic hydrocarbons.