CDP Journal Club: plants and the brain

We are delighted to have Tim Eschle from the University of Northumbria present at the Centre for Dementia Prevention January Journal Club. We were very interested to hear about Tim’s work in the Brain, Performance and Nutrition research centre (BPNRC) focusing on supplements on the human brain. Please see a summary of his presentation below.

Your research is about plants and the brain. Particularly polyphenols – why are they important?

Polyphenols are a group of phytochemicals (plant chemicals) which are produced in a wide range of edible plants. Although not ‘essential’, polyphenols make up an inevitable part of the human diet and can be commonly found in fruits, vegetables, chocolate, teas and coffee. Interestingly, regular polyphenol consumption has attracted great interest, namely due to increasing evidence from suggesting that polyphenol rich foods can exert beneficial effects on human health. For example, resveratrol, a polyphenol found in red wine, has been observed to improve cardiovascular health; this in part, is attributed to its ability to dilate blood vessels and thus increasing blood flow. As an effective supply of blood is essential to the brain, it has also been tentatively suggested that consuming resveratrol may also help indirectly improve brain function and health. Improvements to blood flow are thought to help protect against brain dysfunction and maybe against even vascular dementias in the long term. In the short term, it is possible the blood flow effects of resveratrol can improve brain functioning. This is based upon the concept that an additional supply of blood will increase the supply of the brain’s essential fuels (oxygen & glucose); helping us work harder and fight mental fatigue. This is thought to be particular useful as we get older as the brain tends to suffer a small reduction in blood flow to a few key areas essential for ‘cognitive functioning’, which may be due to the reduced supply of the brain’s ‘fuel’ and in turn, performance. Therefore, my PhD focused on whether supplementing adults with resveratrol, could increase blood flow to the brain and, as a result, improve mental functioning.

What did you find in your research?

In younger adults, we found that resveratrol was able to increase blood flow but wasn’t able to improve mental functioning. However, this is perhaps expected as young, healthy adults tend to have a very effective supply of blood and an already high cognitive performance. In older adults, we unsurprisingly also found that resveratrol was unable to improve cognitive performance. Despite this, the consumption of polyphenols either in from their native food sources or from over the counter supplements has shown some promising evidence in improving or preserving mental functioning. Research into polyphenols and brain functioning still requires a large amount of clarification and investigation, but it is interesting to consider plants and their metabolites have the ability to interact with human health / functioning.