That is according to a study published online ahead of print on the website of the Journal of Clinical Endocrinology and Metabolism (JCEM) earlier this week.
The researchers wanted to see the effect of eating a diet rich in tomato (and therefore lycopene) on biomarkers of obesity. They also looked into the effect of eating a diet rich in soy.
But why I hear you say? Well, lycopene is a potent antioxidant and has been shown to inhibit breast cancer cells and to suppress cellular proliferation. Soy, makes up a large part of the Asian diet and they tend to have less cases of breast cancer compared to America. Also it has been suggested the phytonutrients isoflavones found in soy could contribute the risk of developing breast cancer (paradoxically in either a positive or negative way). Perhaps, not surprisingly, the results thus far have been mixed.
The participants in the trial had a 10 week diet containing increased tomato followed by a short wash out period and then a 10 week soy based diet. The tomato diet caused an increase in the level of adiponectin, a biomarker of obesity (lower in obese people). The soy based diet lead to a decrease.
If it really is the lycopene that is responsible for this effect I wonder if a diet rich in watermelon would have the same effect? Or perhaps Gac fruit?