A new study led by the Charles Perkins Centre at the University of Sydney, examined medical data from nearly half a million people and discovered that being overweight or obese significantly increased the harmful effects of alcohol on liver disease and mortality. Published in the European Journal of Clinical Nutrition, the researchers claim this is one of the first and largest studies to look at the relationship between increased adiposity (obesity) and alcohol consumption, in regards to future liver disease.
“People in the overweight or obese range who drank were found to be at greater risk of liver diseases compared with participants within a healthy weight range who consumed alcohol at the same level,” said Professor Emmanuel Stamatakis of the Charles Perkins Centre, senior author of the paper and the director of the research program.
“Even for people who drank within alcohol guidelines, participants classified as obese were at over 50 percent greater risk of liver disease.”
A comprehensive biomedical longitudinal study that included detailed biological, behavioral, and health information from participants across the UK, called UK Biobank, was used by the researchers as their data source.
465,437 people between the ages of 40 and 69 were studied, with medical and health data collected over an average of 10.5 years.
The researchers looked at data on people who were classed as overweight or obese based on their BMI and waist circumference, self-reported alcohol intake based on UK alcohol recommendations, and liver disease incidence and mortality due to liver disease.
The BMI is calculated by taking into account both weight and height. Overweight is defined as a BMI of over 25, while obesity is defined as a BMI of over 30. The WHO categorization guidelines for waist circumference was used by the researchers: normal (80 cm for women, 94 cm for men), overweight (>80 cm for women, >94 cm for men), and obesity (>88 cm for women, >102 cm for men).
A figure termed a hazard ratio was assigned to the degree of risk associated with alcohol consumption in a given group. The greater the number, the greater the risk.
The study stated that the “results for the associations of alcohol consumption and waist circumference with alcoholic fatty liver disease, non-alcoholic fatty liver disease and liver disease mortality were similar. Participants with high waist circumference who reported alcohol consumption above the guidelines had a greater hazard ratio for liver disease incidence (HR 1.59, 95% CI 1.35, 1.87) than normal WC individuals.”
For those who drank more than the amount suggested by the UK alcohol guidelines, compared to within guideline drinkers, they had a 600% increased chance of being diagnosed with alcoholic fatty liver disease (5.83 hazard ratio). Additionally, they had an approximately 700% increased risk of mortality by alcoholic fatty liver disease (6.94 hazard ratio). People who were overweight or obese who drank within or above alcohol standards had a 50 percent higher risk of developing liver disease than people who were normal weight and consumed alcohol at the same levels.
According to lead author Dr Elif Inan-Eroglu, a postdoctoral research fellow at the Charles Perkins Centre, the findings show that people who are overweight should be more conscious of the hazards associated with alcohol intake.
The researchers suggest that the findings of the study highlight how alcohol consumption standards and doctor’s advice may need to take into account the year-over-year rise in obesity and overweight prevalence, as well as the health implications.
Current alcohol guidelines suggest that men and women should not drink more than 14 units a week on a regular basis and that you should spread your drinking over 3 or more days if you regularly drink as much as 14 units a week.
Professor Stamatakis concluded: “The current alcohol guidelines are based on reviews of available evidence, but future updates must take into account overweight as a liver disease risk amplifying factor.
“Briefly mentioning obesity in the current [alcohol] guidelines may not be enough. Overweight and obesity affect over [1.9 billion people globally], which raises the need to develop a specific alcohol drinking recommendation for this population majority group,” he said.
“Based on our study’s findings, people who are in the overweight range, not only obese, should consume alcohol cautiously, and perhaps aim for an amount well below the generic guidelines.”