URBANA, Ill., March 3 (UPI) -- Eating broccoli three to five times per week has been shown in experiments to reduce the risk for liver cancer, in addition to reducing damage to the liver that increases risk for cancer, according to new research with mice.
Researchers at the University of Illinois found eating broccoli a few times a week can counter the development of fat in the liver, which causes it to malfunction and increases the risk for liver cancer.
The vegetable is known to reduce the risk for other types of cancer, including breast, prostate and colon, so researchers were less surprised by its link to decreased risk for cancer than its effects on diseased livers.
The researchers said they worked specifically with mice that were not genetically predisposed to obesity, opting instead for rodents that became obese because of diet and activity. Their reasoning was most people are not genetically likely to become obese, focusing instead on the effects of the Western diet that has led to three-quarters of Americans being overweight or obese.
"There are actually two ways of getting fatty liver: one, by eating a high-fat, high-sugar diet and the other by drinking too much alcohol," Elizabeth Jeffery, a professor of nutrition at the University of Illinois, said in a press release. "In this case, it is called non-alcoholic fatty liver, because we didn't use the alcohol. And it is something that is becoming prevalent among Americans. This disease means you are no longer controlling the amount of fat that is accumulating in your liver."
For the study, published in the Journal of Nutrition, the researchers gave four groups of mice either a control diet with or without broccoli or a "Western diet" high in lard and sucrose with or without broccoli.
The researchers report that mice on the Western diet had more cancer nodules and larger nodules in their livers, but when broccoli was added to their diets the number of nodules decreased. Additionally, the researchers said the Western diet increased fat retained in the liver, but with broccoli added to their diets, the rodents livers increased the their output of lipids.
Jeffery said the mice did not lose weight when broccoli was added to their diets, but their livers got healthier. This, she said, suggests adding the vegetable to meals can make people healthier.
"I think it's very difficult, particularly given the choices in fast food restaurants, for everybody to eat a lower fat diet," Jeffery said. "But more and more now you can get broccoli almost everywhere you go. Most restaurants will offer broccoli, and it's really a good idea to have it with your meal."