For the assessment, they observed a small group of adults who consumed a tomato extract-based shake with iron and one without it. Researchers then examined the lycopene levels in the subjects’ blood and digestive fluid.
After analyzing the results, they found those who consumed the shake with iron had significantly lower levels of lycopene in their blood and digestive fluid, compared to those who had the shake without iron.
“When people had iron with their meal, we saw almost a twofold drop in lycopene uptake over time,” lead author Rachel Kopec said in a statement.
“This could have potential implications every time a person is consuming something rich in lycopene and iron — say a Bolognese sauce, or an iron-fortified cereal with a side of tomato juice. You’re probably only getting half as much lycopene from this as you would without the iron.”
Although iron helps our bodies produce energy and get rid of waste, its “known to monkey with other cellular-level processes,” the scientists wrote.
While it’s unclear why lycopene levels decline when mixed with iron, researchers hypothesize a meal with iron oxidizes lycopene.
"It’s also possible that iron interrupts the nice emulsified mix of tomato and fats that is critical for cells to absorb the lycopene. It could turn it into a substance like separated salad dressing — oil on top and vinegar on the bottom — that won’t ever mix properly,” Kopec said.
The team now hopes to further their investigations to better understand the relationship between lycopene and cancer, and how it interacts with other compounds.