I was asked to give my thoughts on 'resveratrol' and if I would recommend people to take this as a supplement. After reviewing recent studies, here are my thoughts on it.
For starters, what is it?
They are 'polyphenol compounds' (micro-nutrients) found in certain plants and can have antioxidant properties.
It can very easily be purchased online and can be found in most high-street health or alternative medicine shops in tablet or loose powder form. Potency levels ranging from 500mg to 1000mg and price tags range too.
It can be found naturally in foods such as black grapes, dark chocolate, plums, blueberries, peanuts and red wine.
So, are there any benefits to taking it?
1. Resveratrol could have a positive effect on reducing fasting glucose, and insulin resistance in people with type 2 diabetes. Buuuut, we don't know the effect on people without type 2 diabetes
2. A high dose of resveratrol consumption (higher than or exceeding 150 mg per day) could reduce systolic blood pressure.
This is the top number of a blood pressure reading and measures the force your heart exerts on the walls of your arteries each time it beats. Significant changes in diastolic blood pressure (the bottom number) could not be seen.
3. Studies using rodents with chemically induced Parkinson’s Disease found that resveratrol can have a ‘neuro-protective’ mechanism. These included raising the level of dopamine and its bi-products, improving the antioxidant levels and control the levels of proteins linked with causing motor symptoms in Parkinson’s Disease.
4. Resveratrol’s potentially 'strong antioxidant properties' have been commented on in a lot of the papers. This antioxidant is able to stabilise free radicals.
Free-radicals are bi-products from natural processes that occur in the body or enter the body from outside sources such as exposure to X-rays, ozone, cigarette smoking, air pollutants, and industrial chemicals.
Resveratol could prevent this free-radicals from causing damage to cells in the body
5. Resveratrol’s antioxidant properties also make it anti-inflammatory with a number of studies suggesting that resveratrol can control anti-inflammatory proteins and prevent unwanted inflammation.
Inflammation in response to injury or infection is a vital part of our body's immune system defence.
Too much inflammation especially in an area where there isn't injury or infection can cause aches and can get very painful.
Although there some promising and exciting research on resveratrol, it is important to note that there is not enough good quality research using humans as participant for the findings to be taken as fact.
We don’t know if the effects of ingesting resveratrol orally is because of resveratrol or because of its bi-products as it is broken down by gut bacteria
We are not clear on the ‘optimum’ dose to take to create a desired health response
Although no side effects have been documented from taking it in the short term, long term intake has been associated with nausea, vomiting and diarrhoea in healthy participants and liver dysfunction in patients with non-alcoholic fatty liver disease.
There is not enough research on the long-term effects and side-effects on participants with chronic health conditions such as cancer, Parkinson’s disease or heart failure.
Eating a well-balanced diet and including a variety of fruits and vegetables (aiming for at least 5 portions a day) is the best way and should be the first approach to increasing anti-oxidant intake for healthy adults.
Liu, K., Zhou, R., Wang, B. and Mi, M.-T. (2014). Effect of resveratrol on glucose control and insulin sensitivity: a meta-analysis of 11 randomized controlled trials. The American Journal of Clinical Nutrition, 99(6), pp.1510–1519.
Liu, Y., Ma, W., Zhang, P., He, S. and Huang, D. (2015). Effect of resveratrol on blood pressure: A meta-analysis of randomized controlled trials. Clinical Nutrition, 34(1), pp.27–34.
Su, C.-F., Jiang, L., Zhang, X.-W., Iyaswamy, A. and Li, M. (2021). Resveratrol in Rodent Models of Parkinson’s Disease: A Systematic Review of Experimental Studies. Frontiers in Pharmacology, 12.
Delpino, F.M., Figueiredo, L.M., Caputo, E.L., Mintem, G.C. and Gigante, D.P. (2021). What is the effect of resveratrol on obesity? A systematic review and meta-analysis. Clinical Nutrition ESPEN, 41, pp.59–67.
Salehi, B., Mishra, A., Nigam, M., Sener, B., Kilic, M., Sharifi-Rad, M., Fokou, P., Martins, N. and Sharifi-Rad, J. (2018). Resveratrol: A Double-Edged Sword in Health Benefits. Biomedicines, [online] 6(3), p.91. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6164842/#B46-biomedicines-06-00091.