Red Wine and Tea: Good for You?

Good news for red wine and tea drinkers—your favorite beverages may help control after-meal spikes in your blood glucose levels.


Researchers at the University of Massachusetts, Amherst, have published a study that looked at the effects of two types of wine and four types of tea on the activity of an enzyme, alpha-glucosidase. In the human body, alpha-glucosidase regulates the absorption of glucose by the small intestine, and blocking its action can help reduce the spike in blood glucose levels that can occur in people with diabetes after meals. (In fact, a class of drugs called alpha-glucosidase inhibitors, including Precose [acarbose] and Glyset [miglitol], does just that.)

In their study, which was published on April 3 in the Journal of Food Biochemistry, the researchers tested the effects of red wine and white wine on alpha-glucosidase in test tubes. They found that red wine inhibited the enzyme’s activity by almost 100%, while white wine inhibited it by about 20%. They also tested black, oolong, white, and green teas, and found that black tea inhibited alpha-glucosidase the most of the teas, followed by white tea and oolong tea. What’s more, neither wine nor tea affected another enzyme, pancreatic alpha-amylase, which breaks down starch. Some of the drugs that block alpha-glucosidase action can also block alpha-amylase, which can lead to uncomfortable side effects such as bloating, flatulence, and diarrhea.

The researchers believe that the helpful effects of red wine and tea are related to their high antioxidant content; in particular, to a type of antioxidant called polyphenolics, which are found in many plant-based foods. Polyphenolics may play a role in blocking alpha-glucosidase and slowing the absorption of glucose into the bloodstream. They may also fight oxidative stress in other parts of the body, helping to protect the body from diabetes complications, such as heart disease.

While this study took place in a laboratory and didn’t involve any human subjects, the researchers conclude that it should inspire further study of the use of wine and tea in managing Type 2 diabetes. They also point out that it highlights “the importance of an antioxidant-rich diet as part of an overall management strategy.”

For a more in-depth explanation of how antioxidants work in the body, please see the article “Antioxidants: Should You Supplement?”

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  • Corinne

    I’d wait for new research to finish which debunks that lame “French paradox” idea. Doctors and anyone who likes your money will say drinking is great “in moderation.” But try to find studies that didn’t make money for the funding corporation, because evidence does exist that low to moderate alcohol consumption adversely affects bodily processes, especially hormonal and neurological function. There are several cases in all age groups of my family of remarkable improvement in health and mental alacrity after giving up alcohol. It started with my aunt who’s research into cancer survival rates prompted her to swear off alcohol for good. She survived. Who can say whether it helped, but even if you’re healthy, please find your own information about alcohol affects, don’t be a lemming, or believe what media sources and doctors make money to tell you! Be Well!

  • rememberthecoop

    I thought alcohol and metformin (Glucophage) is a deadly combination? What are we teaching people, that it’s OK for diabetics to drink alcohol? In addition, many diabetics suffer from fatty liver and alcohol is a toxin to the liver and will cause further complications.

  • Shirley

    I agree with the person who believes that Alcohol and Metformin don’t mix. I had to give up my nightly glass of wine with dinner for that exact reason. Plus the blood sugar spike that occur in Diabetic bodies only adds to probable complications. I would forego wine or other spirits for the sake of a healthy liver, kidneys and blood vessels. We won’t even include the effects on one’s high blood pressure and HTN meds. Diabetics.

  • Philbur

    I do 2 beers a day everyday. Helps my cholesterol and has never hurt my glucose. I would do red wine for the above mentioned results, but I do not enjoy wine. Alcohol fits in just fine with diabetes. As with everything, just be aware of how it works with your own treatment. YMMV

  • C.Longa

    I take 500 mg. of metformin as well as two glasses of red wine or beer during dinner and it keeps my glucose well under control (A1c of 6.5 or less after 5 years of type 2). My doctor said it’s okay to take not more than two bottles of beer or glasses of wine. Anything more will be harmful.

  • Steve Parker, M.D.

    Here’s an excerpt from my 2007 book, “The Advanced Mediterranean Diet: Lose Weight, Feel Better, Live Longer”:

    “The ADA recommends limiting alcohol to one drink daily for women, or two drinks daily for men. This low to moderate-level alcohol consumption by diabetics is associated with reduced risk of death from coronary heart disease, and with reduced risk of developing coronary heart disease in the first place. Nevertheless, the ADA does not advocate you start drinking alcohol if you don’t already drink. Nor does the ADA favor one form of alcohol over another. Low level alcohol consumption rarely has a significant effect on blood glucose levels. Low blood sugar levels are, however, at least a theoretical concern if you drink alcohol, especially if you take insulin, a sulfonylurea, a meglitinide, pramlintide, or exetanide. If you drink wine as part of the Advanced Mediterranean Diet, consuming it with food will eliminate the slight chance of low blood sugar. Be aware that the American Association of Clinical Endocrinologists recommends that diabetics avoid or limit the use of alcohol due to unpredictable effects on blood glucose levels.”

    Be sure to check to get your doctor’s blessing before you start drinking alcohol.

    I also recently wrote about the benefits and adverse effects of alcohol at my healthy lifestyle blog:

    -Steve Parker, M.D.

  • Corinne

    To reiterate, please find other sources of information. Most medical professionals get their info from the same place. All respect to doctors and medical professionals, but you all have to admit how hard you dropped the ball on things like the food pyramid and smoking. How many times my grandfather was told by his doctor that a good hearty cigerette after each dinner was just fine. Now he has an oxygen tank. And yet, there were scientists and researchers who very early on were exposing the dangers of recreationally breathing in toxic fumes. Now there are similar studies showing that recreationally consuming poisonous fluids might not be awesome. The studies are not popular because they say things nobody wants to hear. But just like the “free love” of the 60’s, somebody eventually had to point out that fun does not equal wise. I won’t post specific info, because I’m selling nothing. I just want people to be open-minded and not fall into following the crowd, or a medical industry that for generations has been tainted by biased studies and hindered by crooked lawsuits (whatever you pay for malpractice insurance, Steve, I agree that it’s way too much). Again, be well!

  • oyerah

    Your information is helpful for me to understand how to handle my health.

    Thank you.

  • Steve Parker, M.D.

    FYI, I pay $24,000 per year for medical malpractice insurance in Arizona. It’s higher or lower in other states. Doctors either pass the costs on to patients, or go out of business.

  • Kim

    Red wine, great to remain healthy!

  • sukhdev singh

    Can i drink wine ? i m 33 years old and my diabetes value is 227 and 15 days ago it was 500.
    pl. also tell the brand as per indian market

  • jim snell

    great good news.

    Red wine – dry merlot great.
    Alcohol and metformin raises some interesting points.

    For me, sipping glass of red wine no issue.
    hard drink – i enjoy – really gets liver’s attention cutting off gut sugars.

    it also shuts down metformin good points making liver dumps worse and larger. have checked on cgms carefully and fully.

    toxic – don’t know. have been on metformin and some drinking – iam not dead nor have seen bad effects.

    that said i do not drink any hard booze when doses of met up to strength in blood stream.

    best time for me to have a drink – 1 is in am at wakeup when gut empty and system slinking along before met charge loaded. no problems from that.

    i follow mediterranean diet along with some wine and a glass of hard booze.

  • hugo alvarenga guatemala

    ola tuve la oportunidad de viajar a buenos aires argentina y por casualidad vivi en casa de una pareja de esposos de de mas de 70 años, ellos tenian diabetes del tipo 2 desde los 50 años de edad, y bebian vino en todas sus comidas, estaban sanos, cuerdos y felices con niveles de glucosa en mas o menos 150 cada uno !sorpresa! me parece que ningun estudio cientifico va a ser imparcial siempre tienen alguien que paga para inclinar la balanza a sus intereses, creo que la mejor forma de comprobar las cosas es viviendolas, mi esposa es diabetica y toma vino una onza en el almuerzo y talvez otra onza en la cena otra vez !sorpresa! sus niveles de azucar han bajado de 265 a 130 o 150, no digo que sea una medicina, no digo que ella sea alcoholica, lo toma por placer de vida,
    por compartir una noche romantica y sin exceso,
    que esten bien todas las personas del mundo con vino o sin el saludos!!!!!

  • Unbiased wine

    this is one great news!