For some time we already knew that broccoli protects against various types of cancers, but now scientists have also added liver cancer to that list. Lever cancer is linked to obesity and broccoli reduces the absorption of fat in the liver.
Previous studies showed the health benefits of broccoli and the protective effects of the vegetable against breast cancer, prostate cancer and colorectal cancer. Researcher Elizabeth Jeffery of the University of Illinois wanted to study the protective effects of the vegetable for the liver, something which had not yet been done.
In order to do this, Jeffery observed the typical western eating pattern with a menu of saturated fats and added sugars. The consumption of these is, just like having a lot of body fat, linked to non-alcoholic fatty liver disease (NAFLD). This affliction can lead to liver cirrhosis, liver cancer or liver cell carcinoma, a rare but very deadline type of cancer. "We felt that liver cancer had to be researched", says Jeffery, "especially regarding the current obesity epidemic in the United States. It is known that obesity increases the risk of liver cancer, especially for men. In case of obesity, there is five times as much risk of developing liver cancer."
Western diet for mice
The researchers did tests with four groups of mice, in which some mice received a control diet, while others received a "western diet", which represents the diet which many people eat nowadays. Some mice also received broccoli, while others didn't. "We mainly wanted to study mice with obesity, not by a genetic predisposition, but because they followed a diet with a high fat and sugar percentage, as is the case for many westerners nowadays."
In the mice which followed a western diet, the researchers perceived an increase of the amount and growth of cancer cells in their liver. As broccoli was added to the diet, the number of cancer cells decreased. The growth of the present cells remained the same.
The researchers concluded that broccoli reduces the absorption of fat in the liver. The mice which ate broccoli had a liver which was more balanced and they were generally more healthy. "It's not easy for everyone to eat less fatty foods, especially when you regard the large number of fast food restaurants nowadays", says Jeffery. "However, broccoli is available nearly everywhere as a side dish and it's a good idea to amply add this vegetable to your diet." Earlier studies showed that eating broccoli three to five times a week offers the best protection. The best way is to chop broccoli and eat it raw or to steam it lightly.
This study was published in the Journal of Nutrition.