A. Tammy Scott, PhD, an assistant professor in Tufts’ Friedman School who specializes in neuropsychology and dementia research, cautions, “Check with your doctor before starting to take new dietary supplements. If they’ve passed the expiration date, you should toss them regardless.”
Soy lecithin is a common food additive, used as an emulsifier, so you’re probably already getting lots of it in the processed and packaged foods you buy. Despite many enthusiastic posts on the Internet, scientific evidence of its benefits for the brain and nervous system is scant. Most research on soy lecithin dates from the 1980s, when some findings in rats actually suggested it might have negative effects.