Adopting a tomato-rich diet can help lower breast cancer risk in postmenopausal women, according to a Rutgers University study.

Researchers said that a glass of tomato juice contains the right amounts of the lycopene, an antioxidant that is believed to be responsible for lowering the risk of certain types of cancers of the prostate, lung, and stomach.

Lycopene, the plant chemical, increases Adiponectin levels in the body that typically prevents the disease. Adiponectin, a hormone, is known to regulate fat levels and obesity. According to National Cancer Institute, obesity is considered as the main cause of breast cancer.

 "The advantages of eating plenty of tomatoes and tomato-based products, even for a short period, were clearly evident in our findings," Adana Llanos, PhD, MPH, the study's first author and an Assistant Professor of Epidemiology at Rutgers University, said in a press release.

Women, who detest having tomato juice can still consume the plant chemical by having a bowl of tomato soup, pasta with tomato sauce or a spoonful of ketchup a day.

For the study, the researchers measured hormone levels of 70 women, aged 55 and above, who were asked to follow soy or tomato rich diets for a period of 10 weeks each. All the participants faced heightened risk of developing breast disease as they were either obese or had a close relative with breast cancer.

During the first 10 weeks, women consumed at least 25 milligrams of lycopene a day though various tomato products. In the next 10-week period, they ate at least 40 grams of soy protein daily.

The researchers found that when the women were on tomato rich diet, adiponectin levels increased by nine percent. The levels of hormone were high in thinner women.

"The findings demonstrate the importance of obesity prevention. Consuming a diet rich in tomatoes had a larger impact on hormone levels in women who maintained a healthy weight," Llanos said.

Although the study has found tomatoes to be the best of the antioxidant, it is also present in smaller quantities in guavas, watermelons, apricots, papayas and pink grapefruit.

British experts said that the fact that lycopene can be found in other food products, weakens this study. There is no need for them to stockpile tomatoes.

 "Our diet is made up of lots of different foods and nutrients and many of these affect our risk of cancer, often in combination with one another. Eating any one specific food is unlikely to have a major impact on preventing cancer on its own," Yinka Ebo, of Cancer Research UK, said, Daily Mail UK reports.

"There's no need to start stocking up on tomatoes, women can reduce the risk of breast cancer by maintaining a healthy weight, drinking less alcohol and being physically active."

The finding is published in the Journal of Clinical Endocrinology & Metabolism.