Now I want to pivot our conversation into talking about alcohol's effect on health and disease, beginning with alcohol's effect on longevity and aging. Let's be clear from the start, harmful use of alcohol is responsible for more than 200 different disease and injury conditions. In 2016, there were 3 million deaths attributed to alcohol, or around 5.3% of all deaths worldwide. Alcohol is also estimated to be responsible for 131 million years of life lost due to premature mortality or years of healthy life loss due to disability and disease. Alcohol's effect on mortality risk is greater than that for tuberculosis, HIV and AIDS, diabetes, hypertension, digestive diseases, road injuries, and violence. Men seem to have a higher alcohol-attributable burden of disease than women.

Furthermore, the risks of alcohol aren't just for older people. Even in adults aged 20 to 39, approximately 13.5% of all deaths are attributable to alcohol. And over 50% of all alcohol-related deaths occur in adults younger than 60. Like all drugs, when misused, alcohol can cause harm. What's more relevant to most people is how a low-risk drinking habit impacts healthspan and lifespan. That's what I'm going to cover now. One extensively adjusted meta-analysis of over 4.8 million participants did not find any significant association between consuming less than 1 to up to 3 drinks per day with all-cause mortality when compared to lifetime nondrinkers.

People consuming 3 to 5 and more than 5 drinks per day, who the study characterized as high-volume and highest-volume drinkers, had a 19 to 35% greater mortality risk than lifetime nondrinkers. However, the risk was different for men and women. Mortality risk was higher in women than in men and increased even among women having 2 or more drinks per day. In men, mortality risk increased at 3 or more drinks per day. Metabolic differences, body composition, and hormonal factors can cause alcohol to have different impacts on men and women. Women generally have lower gastric levels of the enzyme alcohol dehydrogenase, which helps metabolize alcohol. making them more susceptible to alcohol's effects at lower doses compared to men.

This could explain the increased mortality risk in women compared to men. An important advancement from this study was the finding that while low to moderate volume drinking didn't increase mortality risk compared to abstaining, it didn't provide protection either, as has been suggested by previous large-scale studies. So some studies have found a lower life expectancy in so-called low and moderate drinkers. A study involving nearly 600,000 current drinkers has shown that even what many consider low to moderate levels of drinking can significantly decrease life expectancy. For example, individuals consuming about 8 drinks per week might see a reduction in life expectancy by around 6 months by the age of 40, compared to those who drink 4 or fewer drinks per week.

As the number of drinks increases to 15 and then to 26 drinks per week, The reduction in life expectancy becomes more pronounced, potentially decreasing by 1 to 2 years and 4 to 5 years respectively. Similar results are observed for healthspan. The lowest risk is observed at 0 alcoholic drinks per day, but is still non-significant up to 10 standard drinks per week or less than 1 drink per day. But above 1 standard drink per day, there's a steady increase in mortality risk. I think it is safe to say here that there is no amount of alcohol that increases life expectancy, and it appears at least consistent across several studies that up to 4 drinks per week is not associated with a decrease in life expectancy compared to abstaining from alcohol.

A few FoundMyFitness members had questions about the Blue Zones and why in these countries where people tend to have exceptional longevity, moderate alcohol consumption is typically a large part of the culture. So-called Blue Zones are areas of the world that have an unusually high number of people who are the oldest of the old, which typically refers to centenarians or people who are 100 years or older. Okinawa, Japan, Sardinia, the Greek island of Ikaria, Loma Linda, California are 4 Blue Zones that have been identified and well characterized. It does appear that people in these regions, other than the Seventh-day Adventists of Loma Linda, drink alcohol regularly but moderately, about 1 glass of wine per day.

This is important because in addition to the amount of alcohol consumed, the pattern of consumption likely matters. Drinking 1 glass of wine per day is probably different than drinking 7 glasses of wine on Saturday, even if patterns lead to an average of 7 drinks per week. A low to moderate daily dose characterizes the drinking patterns of the Blue Zones. People in these areas also tend to consume wine with meals, which may also be an important factor. For example, men and women in Ikaria drink more alcohol than people living in other parts of Greece, and 75% of Ikarians reported drinking 1 to 2 glasses of red wine daily. The fact that most of the alcohol consumed in the Blue Zones is red wine is probably important to note.

Given that red wine has been speculated to promote healthspan and longevity due to its high content of polyphenols and other bioactive compounds, even though this is somewhat disputed. And we talked about the low levels of polyphenols such as resveratrol in red wine. Among residents of Okinawa, more men and women report moderate daily drinking compared to the general Japanese population. It's also interesting that many long-lived people from the Blue Zones are former smokers, even though few of them are active smokers. This is one explanation for the exceptional longevity of people in the Blue Zones. They might be particularly good at dealing with toxins such as those present in alcohol and cigarettes.

This would indicate that people in the Blue Zones don't live long because of their moderate daily alcohol intake, but in spite of it. Adopting the drinking habits of people in the Blue Zones probably won't allow you to live as long as them, at least not if you don't have the right genes. One gene known as forkhead box O3A, or FOXO3A, has consistently been associated with human longevity. FOXO3A has a protective role against oxidative stress and is involved in apoptosis, DNA repair, immune cell regulation, carcinogenesis, and stem cell maintenance. Having a protective allele of this gene, or the TT genotype, could explain why people in the Blue Zones live longer despite their moderate alcohol consumption.

But some studies fail to find differences in the prevalence of the protective allele of FOXO3A genes among Blue Zone populations like those in Sardinia compared to other Italians and Greeks. I find it hard to believe that longevity in the Blue Zones is because of direct effects of moderate red wine consumption on health. The social aspects that are associated with moderate alcohol consumption with meals may provide an indirect benefit to health and longevity by improving well-being by reducing stress. That is probably really just the extent of it. So to summarize, there's really no evidence that any amount of alcohol has any positive effect on life expectancy or healthspan.

Even levels of alcohol consumed regularly by large portion of the population appear to increase the risk of death and disease. And the risk isn't limited to those in older age. To optimally reduce your health risks, abstaining from alcohol is recommended. But if you choose to drink, a safe amount for most healthy individuals appears to be 1 to 2 drinks per week on average without exceeding 5 drinks per week, as this level of alcohol consumption does not appear to increase mortality risk compared to abstainers. Finally, while the moderate drinking habits characterized of the Blue Zones are associated with longevity, it's probably not due to a direct benefit of alcohol or red wine, but rather the social aspects that are related to this pattern of alcohol consumption.

Examining the association of alcohol intake with mortality can tell us a lot about how alcohol affects life expectancy of the general population, but it's also useful to assess disease-specific mortality rates so that we can make informed decisions about drinking habits in the context of our own unique health conditions and genetic predispositions.