Is a glass of red wine a day good for heart health?

While consensus has emerged in recent years that no amount of alcohol is good for health, the suggestion that a glass or two of red wine a day is beneficial persists. A recent study by Irish and US scientists suggests that the flavonoid content of red wine can protect older people against fragility and poor mental health. The study reported attributes the benefits to the presence of flavonoids – organic compounds made by plants, that are also present in other food and drink.1

‘A glass (of red wine) a day as part of a diet high in plant rich foods is likely to be good for healthy ageing, but our results suggest a variety of flavonoids are important,’ said Prof Aidín Cassidy of the School of Biological Sciences at Queen’s University Belfast (QUB).

Study participants with the highest ‘flavodiet’ scores – who had higher intakes of red wine, tea, apples, blueberries and oranges – were found to have lower risk of age-related poor health.

But do the flavonoids in red wine cancel out the other potentially life-limiting impacts of consuming alcohol of any type or hue?

In terms of overall health, a systematic analysis for the Global Burden of Disease study 2016 confirmed that alcohol use appears to be the seventh leading risk factor for death globally, leading to millions of people dying annually and resulting in three times more healthy years of life lost than all illicit drug use.2

There is general consensus that binge-drinking, drinking during pregnancy, and heavy drinking are bad for you, but what about light or ‘moderate’ drinking?

Any alcohol consumption leads to detoxification in the body to acetic acid. This leads to the formation of a toxic intermediate, acetaldehyde, that is a known carcinogen and may explain the increased risk of several different cancers, including breast and colorectal – even among light drinkers who only have up to one alcoholic drink a day.3

There is clear evidence that alcohol is addictive and carcinogenic but what about its impact on heart health? In How Not to Age (2023), Dr Michael Gregor discusses this in some detail.

Alcohol does give a boost to HDL cholesterol, but high HDL throughout a lifetime doesn’t appear to lower heart disease risk.4

Added to that, early evidence of atherosclerosis, like the thickening of the carotid arteries, seems to be lowest in those who completely abstain from alcohol.5

Studies of coronary calcium scores show that in general, the lower the alcohol consumption, the lower the risk.6 Alcohol pushes up blood pressure a bit too, which would be expected to raise, not lower cardiac risk.

So where did we get the idea that light or moderate alcohol consumption was good for us? This came from the much-cited J-curve.7

In large populations, followed over time, in general the more people consumed alcohol, the higher their risk of dying prematurely. However, those with the lowest risk, those who tended to live the longest, were not the abstainersc, but those who consumed a few drinks a week.

The mortality versus level of alcohol consumption curve, therefore resembled the letter J, rather than being a straight diagonal line up like upwards.

The ‘sick quitter’ effect arises from the misclassification of former drinkers as lifelong abstainers. The same effect is seen in studies of smokers and non-smokers that include those who quit smoking as non-smokers.

Dr Gregor suggests ‘it’s not that abstention led to poor health but that poor health led to abstention’.

When researchers controlled for the error of misclassifying lifelong abstainers, the J-shaped curve disappeared. The linear relationship between alcohol consumption and both illness and mortality was restored, with no protection at low levels of consumption.8

But what about red wine and all those healthy flavonoids?

A study over two decades of older adults found that any apparent mortality benefits to drinking moderate amounts of red wine seemed to disappear when differences in sociodemographic variables were accounted for.9

‘The grape polyphenols in red wine have antioxidant properties when tested in isolation,’ Dr Gregor says, ‘but alcohol acts as a pro-oxidant, increasing markers of oxidative damage within hours of consumption.’

So, which wins out when you drink them together in wine? Red wine has short-term anti-oxidative effects, but over a period of weeks, consumption of wine, whether white or red, does not reduce markers of oxidative damage – unless the alcohol is removed.10

The study found that even when sugar is added to zero alcohol wine to make the calorie count similar to regular red wine, a month of red wine consumption results in more oxidative damage than the same red wine that has the alcohol removed.

Similarly, non-alcoholic red wine lowers blood pressure but regular red wine does not.11 Does this meant that drinking zero alcohol wine is best – to get the benefits of the polyphenols without the oxidative damaging effects of the alcohol?

A snack of red wine with cheese and crackers causes five times more triglycerides to spill into the blood stream than the same snack with water. Similarly, zero alcohol wine does not cause fat to spill into the blood stream.12 Wine – both red and white – also raises inflammatory markers by 56 per cent (red) and 62 per cent (white)- much higher than sugary drinks (11 per cent).13

The evidence suggests that this inflammatory response could explain how zero alcohol wine improved artery function, while red wine made things worse.14

The most recent advice from the WHO in 2023 is succinct – ‘no level of alcohol consumption is safe for our health,’ Regional Advisor for Alcohol, Illicit Drugs and Prison Health, Dr Carina Ferreira-Borges stated.

“We cannot not talk about a safe level of alcohol use. It doesn’t matter how much you drink, the risk to the drinker’s health starts from the first drop of any alcoholic beverage.”

Just to be clear these studies include all forms of alcohol carrying significant health risks: including red wine, white wine, rosé, spirits and any combination of the above.

The World Heart Federation as well as the Irish Heart Foundation are very clear in their view that alcohol of any form or hue is not good for heart health.

As we come closer to the implementation of alcohol labelling in May 2026, there is mounting pressure from the alcohol industry to delay the implementation. One of the tactics that is being used is to cast doubt on the clear evidence around alcohol and ill-health. The ongoing confusion regarding wine and heart health is an important part of that picture.

If you have got into the habit of a relaxing glass of red wine or two most evenings and have convinced yourself that it is supporting your heart health, there is now robust evidence to suggest that this is not the case.

The best thing we can do for our heart health is to keep alcohol consumption of any kind to a minimum.

Author
Dr Catherine Conlon is a public health doctorand former director of human health and nutrition, safefood.

References:

1. 1. 1. https://doi.org/10.1016/j.ajcnut.2025.02.010
      2. https://pubmed.ncbi.nlm.nih.gov/30146330/
      3. https://pubmed.ncbi.nlm.nih.gov/25422909/
      4. https://pubmed.ncbi.nlm.nih.gov/22607825/
      5. https://pubmed.ncbi.nlm.nih.gov/28525540/
      6. https://pubmed.ncbi.nlm.nih.gov/15718478/
      7. https://pubmed.ncbi.nlm.nih.gov/28818200/
      8. https://pubmed.ncbi.nlm.nih.gov/26997174/
      9. https://pubmed.ncbi.nlm.nih.gov/24588326/
      10. https://pubmed.ncbi.nlm.nih.gov/11295361/
      11. https://pubmed.ncbi.nlm.nih.gov/22955728/
      12. https://pubmed.ncbi.nlm.nih.gov/15530916/
      13. https://pubmed.ncbi.nlm.nih.gov/15015143/
      14. https://pubmed.ncbi.nlm.nih.gov/15585989/