There remains a great controversy about soy. Is it good for you or not? Should you eat it or not? A few years back, a Honolulu study linked tofu to increased cognitive impairment. Now a study suggests it can speed memory loss.
In the study, researchers followed 719 elderly Indonesians. They found that higher tofu consumption might speed memory loss, while fermented soy or tempeh protects. They also said that fruit protected memory. The researchers controlled for age, sex, education, location, and intake of other foods.
Some studies suggest that estrogen can increase dementia risk in women over 65. Soy is loaded with phytoestrogens, which may be the culprit here. Tempeh has lots of phytoestrogens too. But the fermentation process creates much higher levels of folate, which may protect.
However, theres a good reason to suspect this study. It had one huge weakness.
The tofu products in Indonesia contain small amounts of the deadly toxin formaldehyde as a preservative. Formaldehyde is also known as embalming fluid.
If tofu was as deadly as the pundits say, I should have been demented 10 years ago. I used to eat it several times a week. I admit I dropped off my use to less than once a week, partly because of these concerns, and partly because it is not a raw food. I am not sure what the processing involves. So its not my first choice among the soy products.
But overall, my research on soy still remains positive overall, as you will see in the next Health Note. So I am not urging you to avoid tofu and soy. Just keep it in moderation, like everything in life.
Ref: Dement Geriatr Cogn Disord. 2008 June 27;26.