Memory and Diet – What You Eat Can Affect Your Memory

People with diabetes may have memory lapses after eating a high-fat meal, according to a recent report in the journal Nutrition Research. It’s known that people with low HDL-cholesterol levels (the ‘good’ cholesterol) have an increased risk of memory loss over time. Investigating this phenomenon further, Canadian researchers examined the effects of antioxidant supplements on this phenomenon.

Sixteen adults with type 2 diabetes, of average age 64, were fed a high-fat meal, the same test meal with vitamins C (1000 mg) and E (800 IU) tablets, or just water, on 3 separate occasions. At 1 and 1¾ hours after the meal a battery of mental tests were administered, which included measures of delayed verbal memory.

The high-fat meal alone resulted in poorer performance after 1¾ hours on delayed verbal recall and working memory, compared with just water. Taking the antioxidant vitamins together with the high-fat meal resulted in memory test results that were the same as after water intake. These results suggest that oxidative stress is a component of the fatty meal-induced memory decline.

There’s a study from Indonesia, funded by the UK Alzheimer’s Research Trust, which has possibly relevant findings. A high consumption of tofu or other soy products can increase the risk of memory loss. This effect is particularly so in the over-68s.

This finding is hard to explain. Soy products are rich in micronutrients called phytoestrogens (which are not unlike estrogens); these are considered the likely cause of the relationship between soy consumption and memory loss. Previous studies have linked estrogen treatment to an almost doubled risk of dementia in people over 65.

There is no risk, apparently, in moderate consumption of tofu. And it seems that tempeh, a fermented soy product, is associated with improved memory; maybe this is because it contains plenty of folate. Clearly, in this as in other cases, far more research is needed.