polyphenols

Do Muscadine Polyphenols Reduce Skin Aging?

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What Does This Study Mean For You?

Author: Dr. Stephen Chaney 

Red WineNormally, I don’t discuss results from pilot studies. I wait until larger studies have been published in peer reviewed journals. But I thought this study might be of interest to you.

Polyphenols from muscadine grapes and muscadine wine have been reported to reduce cellular aging. So, scientists from the University of Florida decided to do a pilot study asking whether muscadine polyphenols in the diet might improve signs of an aging skin. They reported their results in a poster (L Christman and L Gu, Dealcoholized Muscadine Wine Improved Skin Health, Reduced Oxidative Stress, and Inflammation in Women in a Randomized Controlled Trial, July 24, 2023) presented at the American Society for Nutrition’s NUTRITION 2023 meeting.

They enrolled 17 healthy women ages 40-67 to participate in a randomized, single-blinded, placebo controlled, cross-over study. Simply put, that means:

  • The study started with a 7-day “run-in period” in which their diet was standardized.
  • Then they were asked to drink 10 ounces/day of dealcoholized muscadine wine or a placebo drink for 6 weeks. Since participants did not know which beverage they were given, this is the “single-blind” part of the experimental design.
  • This was followed by a 21-day “wash-out” period to allow muscadine polyphenols to be flushed out of their system.
  • They then were switched to the opposite beverage for an additional 6 weeks. This was the “cross-over” portion of the experimental design.

Their skin conditions and blood markers of inflammation and oxidative stress were measured at the start (baseline) and end of each 6-week portion of the study.

When compared to both baseline and placebo, the dealcoholized muscadine wine significantly improved:

  • Skin elasticity, which prevents the skin from sagging as it ages.
  • Retention of moisture at the skin surface, which indicates the skin is providing a more effective barrier against aging.
  • Skin smoothness.
  • Blood glutathione peroxidase activity, a measure of antioxidant protection.

The authors concluded, “This randomized controlled trial demonstrated that consumption of polyphenol-rich dealcoholized muscadine wine improved skin conditions associated with aging. This is likely due to decreases in inflammation and oxidative stress.”

What Does This Study Mean For You?

Questioning WomanAs for what this study means for you, I have two words, “Stay tuned”.

On the plus side, while muscadine polyphenols have been shown to reduce markers of skin aging when applied to the skin, this is the first study to suggest those same benefits may be seen from the inside out – i.e., from dietary muscadine polyphenols.

On the minus side, this is a pilot study. Pilot studies are meant to test hypotheses to see whether there is enough evidence to justify larger studies. In the words of the authors, “…repeating this study with a larger and more diverse group of people would help to confirm and strengthen the findings going forward.”

So, stay tuned. When the results of larger studies have been published in peer-reviewed scientific journals, I will give you an update.

The Bottom Line 

Scientists at the University of Florida recently did a pilot study to see whether muscadine polyphenols in the diet might improve signs of an aging skin. When compared to a placebo, dealcoholized muscadine wine significantly improved skin elasticity, moisture retention, and smoothness. It also increased blood glutathione peroxidase activity, a measure of antioxidant protection.

The authors concluded, “This randomized controlled trial demonstrated that consumption of polyphenol-rich dealcoholized muscadine wine improved skin conditions associated with aging. This is likely due to decreases in inflammation and oxidative stress.”

On the plus side, while muscadine polyphenols have been shown to reduce markers of skin aging when applied to the skin, this is the first study to suggest those same benefits may be seen from the inside out – i.e., from dietary muscadine polyphenols.

On the minus side, this is a pilot study. Pilot studies are meant to test hypotheses to see whether there is enough evidence to justify larger studies. In the words of the authors, “…repeating this study with a larger and more diverse group of people would help to confirm and strengthen the findings going forward.”

So, stay tuned. When the results of larger studies have been published in peer-reviewed scientific journals, I will give you an update.

For more information on this study read the article above.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease.

 ___________________________________________________________________________

My posts and “Health Tips From the Professor” articles carefully avoid claims about any brand of supplement or manufacturer of supplements. However, I am often asked by representatives of supplement companies if they can share them with their customers.

My answer is, “Yes, as long as you share only the article without any additions or alterations. In particular, you should avoid adding any mention of your company or your company’s products. If you were to do that, you could be making what the FTC and FDA consider a “misleading health claim” that could result in legal action against you and the company you represent.

For more detail about FTC regulations for health claims, see this link.

https://www.ftc.gov/business-guidance/resources/health-products-compliance-guidance

 

 

Are Dietary Polyphenols Associated With Longevity?

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Are Polyphenols The Fountain of Youth?

Author: Dr. Stephen Chaney

Merlot Grapes HDRYou’ve probably heard that resveratrol and other polyphenols in red wine can help mice live longer. But what about us? Are dietary polyphenols associated with longevity in humans?

Until recently nobody knew the answer to that question. However, a recent study (Zamora-Ros et al, J. Nutr. 143: 1445-1450, 2013) suggests that polyphenols may just help us live a bit longer.

Of course, the news headlines make it sound like a sure thing, and many of the manufacturers of polyphenol-containing supplements are already citing the study as “proof” that their products will make you live forever.

Polyphenols Are Everywhere:

So, let me give you some background information before I start diving into the study.

  • The term polyphenols includes some names you may recognize, such as flavonoids, isoflavones, anthrocyanidins and resveratrol, and many more that might look like the kind of names you might expect to find on a processed food label.
  • Polyphenols don’t just come from red wine. There are several hundred polyphenols in edible foods. Many fruits, vegetables (including beans like soybeans) and whole grains – the kinds of foods that every expert recommends for a healthy diet – are also great sources of polyphenols.
  • Most polyphenols are excellent antioxidants. Studies suggest that they may also exert antiinflammatory effects and may reduce the risk of heart disease, neurodegenerative disease and cancer. So it is not unreasonable to assume that they might enhance longevity.

An In-Depth Analysis Of The Study:

The study enrolled 807 men and women over the age of 65 (average age = 74, range = 67-81) from the Chianti region of Italy and followed them for 12 years. At the beginning of the study polyphenol intake of the participants was analyzed from a dietary recall form (polyphenol intake based on what they remembered eating) and from a 24 hour urine specimen (actual polyphenol intake).

During the 12 year follow-up, 34% of the participants died. Based on the dietary recall, there was no association between dietary polyphenol intake and mortality. However, based on urinary polyphenol content there was a 30% decrease in mortality for those with the highest dietary polyphenol intake (>650 mg/day) compared to those with the lowest polyphenol intake (<500 mg/day).

Strengths of the Study:

  • This is the very first study to actually investigate the relationship between dietary polyphenols and longevity in a meaningful way. The study was well designed and well executed.
  • The measurement of urinary polyphenol content is a strength of this study. Dietary recalls are often inaccurate. In fact, this study suggests that dietary recalls should probably not be used to estimate dietary polyphenol intake in future studies.

Weaknesses of the Study:

  • This was a first study of its kind, and like any other first study it needs to be confirmed by additional studies.
  • The study only measured associations, not cause and effect. Of course, it would be almost impossible to conduct a double blind, placebo controlled study of this duration – especially if one is using urinary excretion as a measure of polyphenol intake.
  • The study did not report the dietary sources of the polyphenols, although this information was presumably available from the dietary recalls. Because the study was conducted in the Chianti region of Italy it is probably pretty safe to assume that red wine contributed to the polyphenol intake. However, people in that region of Italy also tend to consume diets rich in fruits and vegetables. Hopefully, future studies will help determine whether some polyphenols are more important for longevity than others.

The Bottom Line:

1)     Eat lots of fresh fruits and vegetables. They’ll make you healthier, and you just may live longer.

2)     If you like red wine, drink it in moderation. Just don’t assume that it can substitute for a healthy diet. This study measured total polyphenols, not just red wine polyphenols.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

Health Tips From The Professor