The nutritional value of meat

Should we eat meat, and in what proportion? Studies of the diets completed by researches on this food.

For lovers of steak and chips, large rumsteack, and other slices of ham and roasts, bad news. Meat is not part of the diet of the 5 blue areas, regions of the world that produce the more centenarians. In these five areas, the diet is the same and the lifestyle too, so there is no doubt that these are the factors of longevity rather than genetics or any other source of youth.

The common factor is a diet rich in vegetables, mostly from their own garden which has the double advantage of organic farming and to bring some exercices.
Another factor is the amount of Omega 3. That comes directly from vegetables, or indirectly from milk or cheese from animals fed with these vegetables rich in O3.

Fat and meat

Fat present in significant proportion in meat, dairy products, are accused to be the cause of diabetes, cardiovascular disease, cancer and other mortality factors.

This is certainly a factor, but it is not so simple. The consumption of sugar in all its forms is probably the factor of overweight and diabetes and these in turn greatly increases the risk of suffering from these ailments.

Meat contains saturated fatty acids. It is a source of cholesterol, but it can be partially counteracted by the Omega 3. They are not a panacea, however, and are not enough to protect you in the case of a carnivorous diet rich in saturated fatty acids.
Other fats, unsaturated such as those found in almonds, walnuts, hazelnuts, dark chocolate, does not increase cholesterol.

So if we know that meat-eating is related to cardiovascular risk, but fatty acids of meat is not enough to explain the resulting mortality. A recent study provides another explanation.

Meat as harmful metabolic factor

Carnitine is a compound synthesized in the liver from lysine and méthonines and also present in large quantities in meat and whose metabolic role is to transport fatty acids into the cells, which contributes to the production of energy.
There are ten times less carnitine in salmon than in beef.

It is used as a dietary supplement and in energy drinks, but a study found that carnitine can be converted by bacteria living in the digestive system into TMAO (trimethylamine oxide). This oxide promotes atherosclerosis and therefore heart risks.
The study is both statistical and experimental. It compared a sample of diet of 2600 patients according to their intake of carnitine, and it also experienced a overdosed carnitine feeding on mice. It was able to verify that the abundance of carnitine increases cholesterol and thus atherosclerosis.
But it also found that among vegetarians, although they consume carnitine in quantity, it is not metabolized to TMAO. The bacterium is present only in carnivores. Meat naturally contains carnitive quantity and it promotes the development of bacteria whose excretions contain this deadly molecule.

The researchers point out that the body does not need a supply of carnitine, he synthesizes it enough itself. The useful contribution of meat is rather in proteins and especially iron. Reducing the consumption of meat, which is recommended, to about 200 grams per week (beside fish and other sources of proteins), therefore requires attention to compensate to iron from other sources.

Référence: Stanley Hazen, Lerner Research Institute and Robert Koeth, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University.