Most people are familiar with the symptoms of Alzheimer’s and know that it affects short-term memory, and in the later stages even long-term memory goes. It also results in a loss of cognitive functions involved in language, recognising people, judging distances, and often culminates in dramatic changes in personality.
In 2011, 48,182 New Zealanders had dementia, an increase of more than 18% in three years, and this trend is expected to continue over the coming decades. Alzheimer’s is not the only form of dementia, but accounts for around two thirds of cases. In the US there are 5.4 million Alzheimer’s sufferers.
It’s still not really known what triggers Alzheimer’s Disease, but it’s likely a combination of factors, including age, genetics and environmental factors. It is understood to be brought on by abnormal proteins in the brain that lead to swelling and cause brain cells to die, as well as being associated with a decrease in certain essential chemicals, but medical science has so far only been able to alleviate the symptoms. And yet the growing body of research on resveratrol as a treatment is cause for excitement.
Two recent studies on the effects of resveratrol on Alzheimer’s patients
Two studies in the US, led by Dr. R Scott Turner, shed some light on the mechanisms of Alzheimer’s. The first trial, published in September 2015 in Neurology, was a one-year study of 119 patients with mild to moderate Alzheimer’s. Half took resveratrol and the other half took a placebo. It had already been established that resveratrol activates sirtuin proteins, which are thought to stimulate mitochondrial function, and are responsible for caloric restriction (restricting the intake of dietary calories), thereby reducing age-related diseases. One thing revealed by the study was that the brains of the resveratrol-takers actually shrank slightly (a good thing in this case), which scientists put down to a reduction in the inflammation observed with Alzheimer’s.
Alzheimer’s patients exhibit a build-up of harmful amyloid-beta proteins in the brain. The first study also indicated that those who received resveratrol showed higher levels of this protein outside the brain (in cerebrospinal fluid samples), than those that took the placebo. It is normally present in the body, only causing problems when it builds up in the brain. This study indicated that resveratrol redresses the balance, with more of the protein circulating in the body and less in the brain.
The findings of second study were revealed at the Alzheimer’s Association International Conference in Toronto July 27 2016. In this trial, 19 patients took resveratrol and 19 a placebo. A particular protein molecule, MMP-9, decreased markedly in the test group but not in the placebo group.
High levels of this protein can cause a breakdown of the blood-brain barrier, allowing dangerous proteins and other neurotoxins in. The resveratrol seemed to actually restore the blood-brain barrier, with a 50% decrease of MMP-9 in test subjects. The study also indicated that resveratrol stimulates the brain’s natural immune response to eliminate neurotoxic proteins.
Diet versus supplements
Resveratrol is a naturally-occurring polyphenol in certain plants, protecting the plant from damage from the sun and microorganisms. Resveratrol can be included in your diet, occurring in blueberries, raspberries, red wine (grape skins), dark chocolate (cocoa), pomegranates, soy, peanuts and itadori tea (also known as knotweed, an ingredient in Res-V Plus and Res-V Ultimate). However, the tiny levels present in these foods mean it’s hard to eat enough to get the effects, and the health risks of excess alcohol and sugar outweigh the benefits of bingeing on, say, wine and chocolate! The small amounts of naturally-occurring resveratrol in your food are also processed and eliminated by the liver too quickly to be effective. A supplement with concentrated amounts of resveratrol is the most effective, especially when combined with other ingredients which make it easier for your body to absorb.
Other health benefits
A number of other health benefits have been associated with resveratrol, including protecting skin from UV (as it does in plants), ‘anti-aging’ effects on mitochondria, fighting cancer and obesity and reducing insulin resistance. According to a review of studies on cancer prevention, “Resveratrol is known to have potent anti-inflammatory and anti-oxidant effects and to inhibit…the growth of a variety of cancer cells.” It has been shown to strengthen the function of mitochondria, which exist in almost every cell in the body and are responsible for energy production, regulation of cell growth, as well as insulin resistance. Resveratrol’s effect on mitochondria explains its “anti-aging action that can prevent/delay the development of age-related diseases in the cardiovascular system and other organs”, according to one study.
One objective of the trials was to observe side-effects of high doses of resveratrol. While some of the participants experienced nausea, diarrhoea and slight weight gain or weight loss, no other side effects were noted. A third trial is planned, to deepen the understanding of both Alzheimer’s and resveratrol, and to answer some of the questions raised by the first two studies.