Red or white?
Red meat in culinary terminology refers to meat which is red-colored when raw, as contrasted with white meat. Beef, pork, lamb are considered "red" while chicken and rabbit are invariably considered "white".
Red meat is one of the richest sources of iron and complete protein. It also contains levels of creatine, minerals such as zinc and phosphorus, and vitamins such as niacin, vitamin B12, thiamin and riboflavin. Red meat is the richest source of Alpha Lipoic Acid, a powerful antioxidant.
However, regular consumption of red meat presents several health risks, largely due to the saturated fat content. including a notable increase in cancer risk, e.g. breast cancer, stomach cancer, bladder cancer, and cardiovascular diseases. Regular consumption of red meat has also been linked to bone loss, type 2 diabetes, hypertension and arthritis.
The healthy eating pyramid recommends that red meat be consumed sparingly.
Meat form intensive chicken farm
Consumption of white meat has risen dramatically over the past few decades, driven by the availability of cheap, mass-produced chicken. However, the recent exposure of conditions in intensive chicken farm questions the value of chicken meat produced from such poor conditions.
The majority of poultry are farmed intensively in battery cages or overcrowded chicken sheds, mutilated and unable to express their natural behaviours. chickens are made to grow super-fast through a combination of genetics, high-protein feed and often growth-promoting chemicals. Their hearts, lungs and bones struggle to keep pace: the skeleton of a 6-week old bird now carries the equivalent weight of a 12-week old bird. As a result, millions of chickens suffer crippling legs or succumb to heart failure.
Animal disease and its impact on meat
Various animal diseases such as foot and mouth disease, bovine spongiform encephalopathy (BSE), and avian influenza (birds flu) cast doubts on beef and chicken.
The pig is not an exception, being the carrier of various helminths, like roundworm, pinworm, hookworm, etc. One of the most dangerous and common is Taenia solium, a type of tapeworm. Tapeworms may transplant to human intestines as well by consuming untreated or uncooked pork.
Eat well, and prosper
Based on the above considerations, I personally think that lamb is the best meat of the four.
Lamb is fairly fatty, and, unlike pork, the fat is not entirely edible - it is more like tallow. This contributes to the high price of lamb, because by the time the lamb is trimmed of its fat and other nonedible parts, the resulting meat is only about 40% of its weight.
Some people are turned off by the smell of lamb, but what they are smelling is burning lamb fat, which does have a very "lamby" odor - for these people I recommend leaner cuts that have been well trimmed.