People who eat a lot of onions, garlic and other alliums have a much lower risk of several types of cancer than those who avoid the pungent herbs, new research shows.
Italian researchers used data from several Italian and Swiss cancer studies to look at the relationship between onion and garlic consumption and cancer at several body sites, including the mouth, larynx, esophagus, colon, breast, ovary, and kidneys, the online edition of health magazine WebMD said.
Researchers Carlotta Galeone, of the Istituto di Ricerche Farmocologiche "Mario Negri" in Milan, and colleagues found that moderate consumption of onions appeared to reduce the risk of colorectal (cancer of the colon and rectum), laryngeal (cancer of the short passageway just below the neck) and ovarian cancers.
Overall, consumption of onions ranged from 0-14 portions per week among cancer patients and 0-22 portions per week among those without cancer.
Garlic use was also lower among people with cancer, except for those with cancer of the breast, ovary, or prostate. They say the health benefits of onion and garlic have been touted for centuries, but few studies have been able to prove the benefits.
The protective effect was even greater among those who ate the most onions compared to those who ate the least. People who ate onions the most also had a lower risk of oral and esophageal cancers than those who ate the least.
Moderate use of garlic was also associated with a lower risk of colorectal and renal cell (a type of kidney cancer) cancers, they said.
Again, the anticancer effect increased with more garlic they ate. People who ate the most garlic had a lower risk of all cancers except breast and prostate cancers, which are mainly associated with hormonal and reproductive issues, write the researchers in the American Journal of Clinical Nutrition.
Researchers say onion and garlic consumption could simply be a marker for a healthier lifestyle and a diet high in a variety of potentially cancer-fighting herbs and vegetables.
However, the protective effect of onions and garlic against cancer remained significant even when they controlled for total vegetable intake.