When talking about food with anti-cancer properties, many studies name tomatoes among the top recommendations for its richness in lycopene compound. A new French-US study looked into the perfect recipes that provide the human body with the maximum benefit.
In the study, which was published in the Molecular Nutrition & Food Research journal, the researchers found that some of the anti-cancer benefits of tomatoes, specifically those from a compound called lycopene, could disappear when they are eaten with iron-rich foods like meats, whole grains, and legumes.
Researchers analyzed the blood and digestive fluid of a small group of French medical students after they consumed either a tomato extract-based shake with iron or one without iron. Lycopene levels in digestive fluid and in the blood were significantly lower when the study subjects drank the liquid meal mixed with an iron supplement.
Iron is essential in the diet, performing such critical functions as allowing our bodies to produce energy and get rid of waste. But it's also a nutrient that is known to monkey with other cellular-level processes.
"We know that if you mix iron with certain compounds it will destroy them, but we didn't know if it would impair potentially beneficial carotenoids, like lycopene, found in fruits and vegetables," wrote lead author, Rachel Kopec, an assistant professor of human nutrition at Ohio State in a report published on the university's website.
Carotenoids are plant pigments with antioxidant properties responsible for many bright red, yellow and orange pigments found in fruits and vegetables. These include lycopene, which is found in abundance in tomatoes and also colors watermelon and pink grapefruit.
Scientists have identified several potential anti-cancer benefits of lycopene, including in prostate, lung and skin cancers.
The study didn't determine what is happening that is changing the uptake of lycopene, but Kopec said: "It could be that the meal with iron oxidizes the lycopene, creating different compounds. It's also possible that iron interrupts the nice emulsified mix of tomato and fats that is critical for cells to absorb the lycopene."
Researchers continue to work to better understand lycopene's role in fighting cancer and the importance of its interplay with other compounds and nutrients.
