The new study, a prospective cohort study published in JAMA Internal Medicine , assessed resveratrol intakes by measuring the concentrations of resveratrol metabolites in the urine, and did not include people taking resveratrol supplements.
According to the findings high urinary resveratrol metabolite concentrations were also not associated with markers of inflammation.
“The story of resveratrol turns out to be another case where you get a lot of hype about health benefits that doesn't stand the test of time,” said study leader Richard Semba, MD, from the Johns Hopkins University School of Medicine. “The thinking was that certain foods are good for you because they contain resveratrol. We didn't find that at all.”
Despite the negative results, Dr Semba added that studies have shown that consumption of red wine, dark chocolate and berries does reduce inflammation in some people and still appears to protect the heart.
“It's just that the benefits, if they are there, must come from other polyphenols or substances found in those foodstuffs,” he said. “These are complex foods, and all we really know from our study is that the benefits are probably not due to resveratrol.”
‘Very little to offer in the way of new or compelling information’
The study has been receiving widespread mainstream media coverage, but James Betz, managing director of Biotivia which produces a resveratrol supplement called Transmax, told us: “As a researcher who has been intimately involved in many collaborations with medical schools, private research organizations, and university scholars over the past ten years I am a bit appalled to see this study receive any attention at all.
“We are well aware of the sirtuin activation, proteonomic, epigenetic, and biochemical effects of Resveratrol at the cellular and extra cellular level. This is not 1994. We not only know that it attenuates the symptomatology of type-2 diabetes and its downstream pathologies, we know to a very great extent how it does this. The same conclusion can now also be stated for resveratrol and cardiovascular disease, and for many solid tumor cancers and at least two variants of leukemia.
“If one bothers to do a quick search on either Google Scholar or Pubmed it becomes immediately evident that, put into context, this small scale, poorly designed, non-placebo controlled, rather casually undertaken study has very little to offer in the way of new or compelling information, nor does it contradict the many thousands of investigations which confirm resveratrol’s health and wellness benefits. .
“This study is actually an investigation of the effects of moderate consumption of a particular variety of red wine. It is by no means an assessment of the effects of the phytoalexin Resveratrol on longevity or health and wellness. The principal fallacy in this study is the researchers claim that the subjects consumed a diet 'rich in resveratrol'.
"It is well known that red wine is not a good source of this compound. The more concentrated varieties, not the ones in fact from the area studied, have on the order of 5mg of Trans-resveratrol per 750cl bottle. The average resveratrol supplement contains 20 times this amount.
"Most clinical and in vitro examinations of resveratrol observe a dose dependent effect. At a dose of 5mg daily, that obtained from consuming an entire bottle of wine the threshold molar concentrations of resveratrol shown to produce its chemoprotective and threaputic benefits could not be attained.”
Resveratrol, a powerful polyphenol and anti-fungal chemical, is often touted as the bioactive compound in grapes and red wine, and has particularly been associated with the so-called 'French Paradox'. The phrase, coined in 1992 by Dr Serge Renaud from Bordeaux University, describes the low incidence of heart disease and obesity among the French, despite their relatively high-fat diet and levels of wine consumption.
Interest in the compound exploded in 2003 when research from David Sinclair and his team from Harvard reported that resveratrol was able to increase the lifespan of yeast cells. The research, published in Nature, was greeted with international media fanfare and ignited flames of hope for an anti-ageing pill.
According to Sinclair’s findings, resveratrol could activate a gene called sirtuin1 (Sirt1 – the yeast equivalent was Sir2), which is also activated during calorie restriction in various species, including monkeys.
Other studies with only resveratrol have reported anti-cancer effects, anti-inflammatory effects, cardiovascular benefits, anti-diabetes potential, energy endurance enhancement, and protection against Alzheimer’s.
On the other hand, data from the Invecchiare in Chianti (InCHIANTI) Study (‘Aging in the Chianti Region’) questioned the polyphenol’s potential health benefits.
The InCHIANTI researchers analyzed data from 783 community-dwelling men and women 65 years or older living in two villages in the Chianti area of Italy. Results showed that there were no differences in the risk of mortality between people with the highest and lowest concentrations of resveratrol metabolites in the urine. Nor were there any associations between resveratrol metabolite concentrations and inflammatory markers, cardiovascular disease or cancer rates.
“In conclusion, this prospective study of nearly 800 older community-dwelling adults shows no association between urinary resveratrol metabolites and longevity,” wrote the researchers. “This study suggests that dietary resveratrol from Western diets in community-dwelling older adults does not have a substantial influence on inflammation, cardiovascular disease, cancer, or longevity.”
'Single entities like resveratrol are seldom the elixirs of longevity'
Commenting on the study, Dr Michael McBurney, PhD, VP Science, Communication & Advocacy – DSM Nutritional Products, told us that resveratrol has been repeatedly demonstrated to have metabolic effects on cellular metabolism.
"However, just as single nutrient interventions do not always change stunting in children, a single dietary ingredient will not always alter life-span," he added. "Nutrients are essential for life and for health. But even single entities like resveratrol are seldom the elixirs of longevity. Lifespan is a complex reflection of diet, exercise and healthy behaviors."
For a more complete review of the study by Dr McBurney, please click HERE .
Source: JAMA Internal Medicine
Published online, doi:10.1001/jamainternmed.2014.1582
“Resveratrol Levels and All-Cause Mortality in Older Community-Dwelling Adults”
Authors: R.D. Semba, L. Ferrucci, B. Bartali, et al.