Breast cancer: eating garlic and onions to reduce the risk?

The health benefits of garlic and onion are regularly highlighted by science. A few years ago, British scientists discovered that a medieval recipe based on garlic, onion, wine, copper and cow bile could overcome the terrible staphylococcus aureus, a superbug resistant to antibiotics. We also know that garlic and onion help fight against diseases such as diabetes, heart problems or colorectal, gastric and prostate cancer. But according to a new study published in the journal Nutrition and Cancerthese foods would also reduce the risk of breast cancer.

To reach these conclusions, researchers from the University of Buffalo (USA) looked at the small American island of Puerto Rico, known for its low rate of breast cancer. They identified 314 women who were diagnosed with the disease between 2008 and 2014 and compared them to 346 volunteers with no history of cancer by asking all the women to answer a questionnaire about their diet. After taking into account factors like age, education, family history, BMI and smoking status, the researchers found an association between moderate and high garlic and onion consumption and cases of breast cancer. .

The researchers wanted to study the population of Puerto Rico because women there consume more onions and garlic than in Europe and the United States, largely due to the popularity of sofrito, a hot sauce made from grated tomatoes. and onions sautéed in olive oil, as well as in bean and rice dishes. What’s more, “Puerto Rico has lower breast cancer rates than the continental United States, making it an important population to study,” says Gauri Desai, an epidemiology student at the School of Health. from the University of Buffalo (USA) and lead author of the study.

A one-of-a-kind study

“We found that among Puerto Ricans, the combined consumption of onion and garlic, as well as sofrito was associated with a reduced risk of breast cancer,” she adds. In detail, those who consumed sofrito more than once a day had a 67% reduction in the risk of breast cancer compared to those who never ate it. “The study of Puerto Rican women who consume a lot of onions and garlic as a sofrito is unique,” she adds, pointing out that it is the total consumption of onions and garlic that makes the difference in breast cancer term.

“There is very little research on breast cancer in Puerto Rico. This study is the result of a collaboration between my colleagues at the University at Buffalo and the University of Puerto Rico to help us understand why the rates are lower there than in the rest of the United States and why they continue to increase while they decrease in the rest of the United States,” concludes Jo Freudenheim, PhD, co-author of the study.

The flavonols and organosulfur compounds in question

Although the latter cannot explain the exact mechanisms involved, the researchers suspect flavonols and organosulfur compounds, very important in garlic and onions, to be responsible for these anti-cancer effects. Garlic contains compounds such as S-allylcysteine, diallyl sulfide and diallyl disulfide, while onions contain alk(en)yl cysteine ​​sulphoxides. “These compounds show anticarcinogenic properties in humans, as well as in experimental animal studies,” says study lead author Lina Mu, who is an associate professor of epidemiology and environmental health at the University at Buffalo. .

These results appear whereas in France the operation Pink October encourages women aged 50 to 74 to take part in an organized screening campaign against breast cancer. With approximately 54,062 new people affected each year in France, breast cancer is the most common female cancer and also the most deadly (11,886 deaths per year). Less than 10% of these diseases occur before the age of 40. The incidence then increases steadily until age 65.