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Alcohol consumption has been a controversial topic in the health and wellness community for years. While some studies have suggested that moderate alcohol consumption can have health benefits, others have found a strong association between alcohol consumption and all-cause mortality. A recent systematic review and meta-analysis of 107 cohort studies conducted between 1980 and 2021 sheds new light on this topic and provides valuable insights into the association between alcohol intake and mortality, particularly in relation to longevity and healthspan.

The history of human alcohol consumption dates back far longer than controversy regarding its effect on longevity. Indeed, alcohol was sometimes the only safe liquid to drink when clean drinking water was a rarity. Alcohol consumption can be dated to the Neolithic period, around 10,000 BCE. Archaeological evidence suggests that humans in the Middle East and China were fermenting beverages from ingredients like grapes, rice, and honey during this time. The earliest evidence of a specific alcoholic beverage is a 9,000-year-old Chinese fermented beverage made from rice, honey, and fruit. Other ancient fermented beverages include mead made from honey and wine made from grapes. The consumption of alcoholic beverages has been an important part of human culture for thousands of years.

Sumeria, located in modern-day Iraq, was one of the earliest civilisations in the world, and its people were known for their advancements in agriculture, metallurgy, and writing.

Sumerians were skilled brewers and consumed beer on a daily basis. They brewed their beer from barley, which was a staple crop in the region. The beer was made by baking barley bread, crumbling it, and then soaking it in water. The mixture was then left to ferment, with the natural yeast present in the air causing the liquid to turn into beer.

Beer was an important part of Sumerian culture, and it was consumed during religious ceremonies, as well as in everyday life. The Sumerians even had a goddess of beer, named Ninkasi, who was worshipped for her ability to provide them with the drink.

Alcohol consumption has been around for thousands of years. I have always thought it odd that something that has endured for so long could be dangerous in moderation. The objective of this recent study was to investigate the association between alcohol use and all-cause mortality. It also had another objective. To find out how sources of bias may change results. Sources of bias include, “former drinker bias” where previous drinkers are lumped together with lifelong abstainers. The data sources were a systematic search of PubMed and Web of Science, which identified studies published between January 1980 and July 2021. Cohort studies were identified by systematic review to facilitate comparisons of studies with and without some degree of controls for biases affecting distinctions between abstainers and drinkers.

The study identified 107 studies of alcohol use and all-cause mortality published from 1980 to July 2021, with 4,838,825 participants and 425,564 deaths available for analysis. Mixed linear regression models were used to model relative risks, first pooled for all studies and then stratified by cohort median age (<56 vs ≥56 years) and sex (male vs female). The data were analyzed from September 2021 to August 2022.

The study found that higher amounts of alcohol consumption were associated with an increased risk of all-cause mortality. This finding was statistically significant, indicating that excessive alcohol consumption can have serious health consequences. The study also revealed that there was a reduction in the all-cause mortality rate among occasional drinkers compared with nondrinkers, but this finding was not statistically significant. This finding confirms a J-shaped risk. That is, there is a protective association at low amounts of alcohol and increasing risk at higher amounts. Interestingly, J-shaped curves appear a lot in longevity. Particularly in relation to exercise and longevity. 

The results of the study were then further analysed based on sex, and it was found that females had an increased risk of all-cause mortality at lower levels of alcohol consumption. This is an important finding as it highlights the need to consider sex-specific recommendations for alcohol consumption to promote longevity and healthspan.

The study also compared its results with those of previous meta-analyses and found that the risk estimates may have been affected by the number and quality of studies available at the time, especially those for women and younger cohorts. This highlights how important it is to continue to conduct high-quality studies on the association between alcohol use and mortality to better understand its effects on longevity and healthspan.

This updated systematic review and meta-analysis provides the best current evidence that daily low or moderate alcohol intake is not significantly associated with all-cause mortality risk, while the increased risk is evident at higher consumption levels, starting at lower levels for women than men. The study suggests that drinking more than 25 g, or 3 UK units, of alcohol per day or more is associated with an increased risk of mortality. 3 units are just over a pint of 4% beer or a small glass of wine. This is a critical finding for improving longevity and healthspan given that excessive alcohol consumption can lead to numerous health problems, including liver disease, cancer, and cardiovascular disease. In the context of human history, the study findings make sense when it is considered that for most of human history beer had a low alcohol content. 

Dr J Hugh Coyne 

Private GP 

Parsons Green, Fulham