In the many well-funded marketing claims of homeopaths and 'alternative' medicine claims, including a US government program that spends $120 million a year legitimizing treatments that don't work, what can easily get lost is data about what natural treatments do work.

The human brain is tricky but animal models at least provide some initial guidance. A new study presented  at Neuroscience 2013 found that enhanced extracts of spearmint and rosemary improved learning and memory.  The novel antioxidant-based ingredient was made from spearmint extract and two different doses of a similar antioxidant made from rosemary extract on mice that have age-related cognitive decline. 

"We found that these proprietary compounds reduce deficits caused by mild cognitive impairment, which can be a precursor to Alzheimer's disease," said Susan Farr, Ph.D., research professor geriatrics at Saint Louis University School of Medicine. "This probably means eating spearmint and rosemary is good for you. However, our experiments were in an animal model and I don't know how much – or if any amount – of these herbs people would have to consume for learning and memory to improve. In other words, I'm not suggesting that people chew more gum at this point."

Susan Farr, Ph.D., associate professor of geriatrics at Saint Louis
University. Credit: Saint Louis University

Farr found that the higher dose rosemary extract compound was the most powerful in improving memory and learning in three tested behaviors. The lower dose rosemary extract improved memory in two of the behavioral tests, as did the compound made from spearmint extract.

Further, there were signs of reduced oxidative stress, which is considered a hallmark of age-related decline, in the part of the brain that controls learning and memory.

"Our research suggests these extracts made from herbs might have beneficial effects on altering the course of age-associated cognitive decline," Farr said. "It's worth additional study."