Red meat

For other uses, see Red meat (disambiguation).

Thinly sliced raw beef

File:Aufgeschnittenes Filet vom Rind April 2013.JPG

Roast beef

Commonly, especially in gastronomy, red meat is red when raw and not pale in color when cooked, in contrast to white meat, which is pale in color before and after cooking. This definition only refers to flesh from mammals or fowl.

In nutritional science, red meat is defined as any meat that has more myoglobin than white meat, white meat being defined as non-dark meat from chicken (excluding leg or thigh), or fish. Some meat, like pork, for example, is red meat using the nutritional definition, and white meat using the common definition.

Definition

Concentration of myoglobin by percentage of mass

Name	Myoglobin	USDA Category
Chicken Breast	0.005%	White Meat
Chicken Thigh	0.18 - 0.20%	Dark Meat
Turkey Thigh	0.25 - 0.30%	Dark Meat
Pork	0.10 - 0.30%	Red Meat
Veal	0.10 - 0.30%	Red Meat
Beef	0.40 - 1.00%	Red Meat
Old beef	1.50 - 2.00%	Red Meat

According to the USDA, all meats obtained from mammals (regardless of cut or age) are red meats because they contain more myoglobin than white meat chicken or fish.

The culinary definition has many rules and exceptions. Generally meat from mammals (for example cattle, horse meat, bull meat) and meat from hunting (wild boars, deer, pigeons, partridges, quail and pheasant) excluding fish and insects are considered red meat. Although poultry is usually considered white, duck and goose are red. For some animals the culinary definition of red meat differs by cut, and sometimes by the age of the animal is when it was slaughtered. Pork is considered red if the animal is adult, but white if young (e.g. suckling pig) the same applies to young lamb, and veal. Game is sometimes put in a separate category altogether. (French: viandes noires — "dark meats".)

Although the USDA classifies pork as a red meat, given nutritional concerns, meat producers are eager to have their products considered "white", so the United States National Pork Board has positioned their product as "Pork. The Other White Meat", potentially using the confusion over the gastronomic and nutritional definition of red meat to imply that it is a safer product.

Nutrition

Red meat contains large amounts of iron, creatine, minerals such as zinc and phosphorus, and B-vitamins: (niacin, vitamin B₁₂, thiamin and riboflavin). Red meat is the richest source of lipoic acid, a powerful antioxidant.

Red meat contains small amounts of vitamin D. The liver contains much higher quantities than other parts of the animal.

USDA recommendations

The 1992 edition of the USDA food guide pyramid has been criticized for not distinguishing between red meat and other types of meat. The 2005 edition, MyPyramid, was confusing but the accompanying website stated that "fish, nuts, and seeds contain healthy oils, so choose these foods frequently instead of meat or poultry" and for people who wanted to eat meat, it recommended lean or low-fat red meat and poultry.

In 2011, the USDA launched MyPlate, which didn't distinguish between kinds of meat, but did recommend eating at least 8 oz of fish each week.

Healthy Eating Plate

In 2011, the Harvard School of Public Health launched the Healthy Eating Plate to better communicate with the public and to make different recommendations than the USDA, which has to contend with lobbying from many quarters. The Healthy Eating Plate encourages consumers to limit red meat and avoid processed meat, and to instead choose fish, poultry, beans or nuts. Its website says: "Eating a lot of red meat and processed meat has been linked to increased risk of heart disease, diabetes, and colon cancer. So it’s best to avoid processed meat, and to limit red meat to no more than twice a week. Switching to fish, chicken, nuts, or beans in place of red meat and processed meat can improve cholesterol levels and can lower the risk of heart disease and diabetes.

Human health

See also: Beef § Health concerns

Red meat is not a uniform product; its health effects can vary based on fat content, processing and preparation. Processed red meat is strongly linked to higher mortality, mainly due to cardiovascular diseases and cancer. There is some evidence too that the consumption of unprocessed red meat may have negative health effects in humans.

Red meat

According to the International Agency for Research on Cancer, a part of the World Health Organization, red meat is probably carcinogenic to humans, with possible risks for colorectal cancer, pancreatic cancer, and prostate cancer. There is no good evidence that red meat consumption increases breast cancer or prostate cancer risk according to a 2010 study. Red meat itself contains certain factors that, under certain conditions, produce carcinogens like N-nitroso compounds (NOCs).

The consensus on the role of red meat consumption to increased risk of cardiovascular diseases has changed in recent years. Studies that differentiate between processed and fresh red meat have failed to find a link between unprocessed red meat consumption and heart disease. A major Harvard University meta-study in 2010 involving over one million people who ate meat found that only processed meat had an adverse risk in relation to coronary heart disease. The study suggests that the "differences in salt and preservatives, rather than fats, might explain the higher risk of heart disease and diabetes seen with processed meats, but not with unprocessed red meats."

Red meat intake has been associated with an increased risk of type II diabetes. Interventions in which red meat is removed from the diet can lower albuminuria levels. Replacing red meat with a low protein or chicken diet can improve glomerular filtration rate. Other findings have suggested that the association may be due to saturated fat, trans fat and dietary cholesterol, rather than red meat per se. One study estimated that “substitutions of one serving of nuts, low-fat dairy, and whole grains per day for one serving of red meat per day were associated with a 16–35% lower risk of type 2 diabetes”.

Processed meat

Eating processed meat (eg, bacon, ham, hot dogs, sausages) is linked to some cancers according to the International Agency for Research on Cancer of the World Health Organization. Epidemiological studies have found that an increased consumption of processed meat is associated with an increased risk of colorectal cancer. While two studies indicate that the risk associated with processed meat is unrelated to white meat like chicken., IARC's Press Release 240, based on a review of 800 studies over 20 years does not distinguish in this manner, defining processed meat as follows: Processed meat refers to meat that has been transformed through salting, curing, fermentation, smoking, or other processes to enhance flavour or improve preservation. Most processed meats contain pork or beef, but processed meats may also contain other red meats, poultry, offal, or meat by-products such as blood.

Nitrates and nitrites found in processed meat (e.g. bacon, ham, salami, pepperoni, hot dogs, and some sausages) can be converted by our body into nitrosamines that can be carcinogenic, causing mutation in the colorectal cell line, thereby causing tumorigenesis and eventually leading to cancer.

Cooking any meat at high temperature and smoking produces the carcinogens polycyclic aromatic hydrocarbon compounds (PAHs) and heterocyclic amines (HCA). Likely because of these factors, marinating fresh lean red meat and thoroughly cooking the meat at low temperature will reduce the production of carcinogenic compounds and thereby lower the risk of colorectal cancer.

Cancer

The World Cancer Research Fund (WCRF) and American Institute for Cancer Research (AICR) classify red meat consumption as carrying an increased risk of contracting bowel cancer. In the United Kingdom approximately 21% of bowel cancers are associated with red meat consumption. The WCRF recommends limiting intake of red meat to less than 300g (11 oz) cooked weight per week, "very little, if any of which to be processed."

There is suggestive evidence that red meat intake might increase the risk of esophageal, pancreatic, stomach, endometrial, lung, and bladder cancer.

Cardiovascular disease

Some mechanisms that have been suggested for why red meat consumption is a risk factor for cardiovascular disease include: its impact on serum cholesterol, that red meat contains arachidonic acid, heme iron, homocysteine, and its high saturated fat content. Bacteria in the digestive tract of people who eat meat have been found to produce a spike in TMAO when supplied with carnitine (abundant in red meat). TMAO is a metabolite that promotes atherosclerosis, a thickening of the arteries.

Other health issues

Regular consumption of red meat has also been linked to hypertension, and arthritis.

External links

• International Association for Research on Cancer, press release 240, 26. October 2015
• IARC Monographs Q&A
• IARC Monographs Q&A on the carcinogenicity of the consumption of red meat and processed meat.