“Onion cancer treatment” is a common claim spread on the internet. Due to many beneficial compounds in the vegetable many claims are attributed to it. However, the question is there any research confirming cancer fighting properties of this vegetable? Keep reading this article to discover what several recent studies have found on onion and cancer prevention.
Onion is widely cultivated and eaten as vegetable. It is distinct for its strong flavor and odor in addition to its health benefits. The bulb has been harvested and eaten as a vegetable almost worldwide from ancient time. In fact, it is said onion was considered as the food of the gods by the ancient Egyptians. This is both a vegetable and precious condiment which has many medicinal properties.
There are nearly 900 varieties of onions, among them shallot, which is used to flavor salads and raw vegetables, and go into the making of sauces, broths, or accompany meat dishes. It has a flavor greater than that of the onion.
Nutritional and Medicinal Properties of Onion
As garlic, in the same category, onion has the properties to increase the physiological pH and dissolve uric acid (whose accumulation can cause gout disease which affects the joints, and decreases the renal functions) in the body. In addition, the vegetable has been found to have anticancer properties in fighting many forms of malignant tumors: colon cancer, prostate cancer, breast cancer, and others.
The different varieties of onions are rich in various polyphenols, known antioxidants. The shallot has the most total polyphenols, while the yellow onion has the highest rate of flavonoids (11 times more than the white onion). The red onion, however, is rich in anthocyanins as well as in quercetin, a polyphenol considered as one of the most powerful antioxidant. Among these polyphenols, onions contain tannins, known for their beneficial effects on the function of the body including the urinary system and on the prostate gland.
Onion and Cancer Prevention
Several prospective epidemiological studies have shown that a high consumption of fruits and vegetables decreased the risk of cardiovascular disease, certain cancers and other chronic diseases. More specifically, studies indicate that consumption of vegetables in the allium family (onions, garlic, chives, green onion, leeks) may have a preventive effect against cancers of the stomach and intestine. Until now, data are insufficient to establish a link with other types of cancers.
In addition, onions contain, among others, trace elements, multiple B vitamins, sulfur and potassium.
Selenium. Like broccoli and garlic, onion has the ability to accumulate selenium from the soil, and provides it to the body when consumed. While it is difficult to quantify its benefits, studies show selenium, in its natural form, helps in the prevention of many cancers: thyroid cancer, prostate cancer, as well as cancers of the esophagus, stomach, liver and bladder.
Manganese. Onion is a great source of manganese for women, given the need is greater in men. Manganese acts as a cofactor of several enzymes that facilitate a dozen different metabolic processes. The mineral also helps prevent damage caused by free radicals. Some small studies have shown that manganese deficiency has been associated with cancer.
Vitamin B6. Onion is an ideal source of vitamin B6. Also called pyridoxine, vitamin B6 is part of coenzyme involved in the metabolism of proteins and fatty acids and the production of neurotransmitters (messengers in the nerve impulses). It also collaborates in the production of red blood cells and allows them to carry more oxygen. Pyridoxine is also necessary for the transformation of glycogen into glucose and contributes to the proper functioning of the immune system. Finally, this vitamin plays a role in the formation of certain components of nerve cells. One of the main roles of Vitamin B6 in fighting against cancer is the fact it strengthens the immune system.
Vitamin C. Onion is a source of vitamin C. The role of vitamin C in the body goes beyond its antioxidant properties; it also contributes to healthy bones, cartilage, teeth and gums. In addition, it protects against infections, promotes the absorption of iron from plants and accelerates healing. High-dose vitamin C has been studied as a cancer treatment since the 1970s, according to the National Cancer Institute. Laboratory studies have shown that high doses of vitamin C may slow the growth and spread of prostate, pancreatic, liver, colon, larynx, ovary, oral cavity and pharynx, and other types of cancer cells.
Sulfur. Onions, as well as garlic, shallots, and leeks, contain various organosulfur compounds. Among many functions of sulfur includes transport of oxygen across cell membranes. Healthy cells need oxygen for cellular regeneration in humans, whereas cancerous cells need lack of oxygen to grow and proliferate. Research has shown organosulfur compounds from onions have powerful anti-cancer properties against many types of malignant tumors.
“Onion Cancer Treatment”
Onion may act at different stages of cancer development. Indeed, studies show that extracts of the vegetable can inhibit the mutation process that triggers cancerous formation. They also decrease proliferation of cancerous cells even after diagnosis. These results come from studies in vitro and in animals. However, the compounds concerned and the specific mechanisms of action require more research to better identify. In addition, the vegetable only cannot be considered or used as a therapy. That is, it is not wise to take seriously this “onion cancer treatment” claim and not seek real therapy to fight the disease in case you have been diagnosed with cancer.
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