Tofu hasn't had the best rap sheet—it is continuously lambasted for tasting too bland and for being used to make unpalatable faux meat products. Additionally, while it is often seen as a health food, it has also been attacked for posing certain health risks. The latest risks come from a new study suggesting that high consumption of certain soy products, including tofu, may increase risk of dementia, particularly for people over 65.

Researchers say that phytoestrogens—micronutrients in soy products that mimic the function of the estrogen hormone—could be to blame. While phytoestrogens may help protect the brains of younger and middle-aged people, their tendency to promote cell growth may have a negative effect on aging brains. Increased levels of estrogen may also promote cell damage caused by free radicals.

Alternatively, the study found out that eating tempeh, a fermented soy product, actually improved memory, perhaps because it contains high levels of folate, known to reduce the risk of dementia.