March 15, 2014 by Ethan Evers
Researchers recently found that flavonoids extracted from onions slowed the rate of colon cancer in mice as effectively as chemotherapy drugs. And while chemo-treated mice suffer from an increase in bad cholesterol, a possible side effect of the drug, onion extract only lowers bad cholesterol in mice.
Onion flavonoids slow down colon tumor growth by 67% in vivo.
In this study, the scientists fed mice a high-fat diet. Fatty foods have been used to cause high blood cholesterol levels (hyperlipidemia), as this is a major risk factor for colon cancer, including in humans.
In addition to fatty foods, one group of mice received flavonoids isolated from onions, the second received a chemotherapy drug, and the third (control) received saline. High doses of onion extract slowed the growth of colon tumors by 67% compared to the control group after three weeks. Chemistry mice also had a slower rate of cancer development, but there were no statistically significant differences compared with high doses of onion extract.
However, there was a significant difference in the side effects experienced by the mice. Chemotherapy drugs are known to have serious side effects. The drug used in this study was no exception – over a hundred possible side effects are known, including coma, temporary blindness, loss of the ability to speak, convulsions, paralysis.
The chemo drug is also known to cause hyperlipidemia (high cholesterol and/or triglycerides) in humans, and this is exactly what happened to mice – their cholesterol levels rose significantly. Onion extract had the opposite effect and significantly reduced cholesterol levels in mice. By as much as 60% compared to the control group.
It’s impressive! And this is not surprising. Onions are known to have the ability to reduce blood fat, and according to a recent study, total cholesterol and atherogenic index in healthy young women as early as two weeks. But how many onions do you need for a positive effect in the fight against cancer? Unfortunately, the authors of the study did not disclose how much of the extract was used.
However, a recent study from Europe provides some clues as to what dosage of onion can produce a significant anti-cancer effect.
Garlic, leeks, green onions, shallots – all these vegetables have been shown to protect against several types of cancer. A recent study in Switzerland and Italy shed light on how much to eat onions. Eating fewer than seven servings of onions per week had minimal impact. However, eating more than seven servings per week (one serving – 80 g) remarkably reduces the risk of developing such types of cancer: mouth and pharynx – by 84%, larynx – by 83%, ovaries – by 73%, prostate – by 71% , intestines – by 56%, kidneys – by 38%, breasts – by 25%.
We see that the healthy, whole foods we eat can have a significant impact on our health and reduce our risk of cancer if we just eat enough of them. Maybe food really is the best medicine.