In the fight against cancer, there is a surprising tool in the arsenal: the food we eat. That’s because some nutrients in food have been found to play a role in preventing cancer, and it’s relevant because the World Cancer Research Fund reports that 30 to 50 percent of cancer cases are preventable, putting a focus on stopping cancer from developing in the first place.Lycopene

Xiang-Dong Wang, a senior scientist and associate director of the Jean Mayer USDA Human Research Center on Aging at Tufts, studies how food can help prevent cancer development, particularly lung, liver, and colon cancer.

Although the rate of most cancers is dropping, there is increasing concern about the rise in both incidence and death rate of liver cancer in the United States, partially due to the parallel rise in nonalcoholic fatty liver disease, obesity, and diabetes.

One food of interest is tomatoes and tomato products rich in lycopene, a naturally occurring pigment that gives many fruits and vegetables their reddish hue.

In a research study recently published in the journal Cancer Prevention Research, Wang’s Nutrition and Cancer Biology lab examined the cancer preventive effects of tomatoes as a whole food rich in lycopene. In infancy, mice were infected with a liver carcinogen and then fed an unhealthy high fat diet, akin to a Western diet, with or without tomato powder containing lycopene.

Researchers then evaluated how well the tomato powder protected mice against inflammation and cancer. In humans, the equivalent supplementation amounts to eating two to three tomatoes a day or a serving of tomato sauce over pasta.
What do we know about lycopene?

The richest source of lycopene is from tomatoes. Other foods, including guava, watermelon, grapefruit, papaya, and sweet red pepper also contain lycopene, but in much lower concentrations compared to tomatoes. Eating tomatoes and tomato products such as tomato sauce rich in lycopene is associated with a lower risk of cardiovascular disease, osteoporosis, diabetes, and certain cancers, including prostate, lung, breast, and colon cancer.

Although these associations come from observational studies, many laboratory studies have demonstrated that lycopene is a strong antioxidant, anti-inflammatory and anti-cancer agent.

How can we maximize the benefits of lycopene?

Consuming whole foods, like tomatoes and processed tomatoes from sauces, tomato paste, canned whole tomato products, ketchup and juice, provides the best source of lycopene. Cooking tomatoes and adding a small amount of fat, like olive oil, can help improve lycopene absorption.