Obesity is now considered a major public health problem. Its prevalence has increased significantly in recent decades and it is believed that the determinants of excess weight include a combination of factors: biological, behavioral, environmental, social and economic ones (1). In addition, obesity is also an important risk factor for the development of diseases, since abdominal fat contributes to determining the risk of cardiovascular diseases and metabolic disorders, for example (1).
Among the many problems associated with harmful alcohol consumption, the relationship between alcohol consumption and body weight has been extensively studied in recent years. Since 1 gram of alcohol provides 7.1 kcal (29 kJ), studies have shown that alcohol consumption contributes to excess energy associated with weight gain (2). Considering that a 350 ml can of beer or a glass of wine corresponds to a standard alcohol drink, which contains 14 grams of pure alcohol, the contribution is significant.
Many factors influence the body's ability to absorb alcohol and its tolerance for alcoholic beverages. Because ethanol is not soluble in fat, a very small percentage of alcohol, when ingested, is retained in adipose tissue (3). Thus, if two people are the same weight but one has more body fat, after the same number of drinks, the person with more body fat will have a higher blood alcohol concentration. That is, being overweight is not a justification for increasing the consumption of alcoholic beverages, because, contrary to what one might think, the abusive consumption of alcohol combined with being overweight can generate even more negative health consequences (4).
Aiming to clarify the association between alcohol and obesity, a Korean study (5) with more than 100,000 men showed that high alcohol consumption (more than 28 drinks per week) was associated with greater risks of obesity, hypertension and dyslipidemia (levels of abnormally high cholesterol), but there was no association with an increased risk of diabetes.
Another point of concern related to alcohol consumption in conjunction with overweight or obesity is the risk of developing liver disease that results from the combination of these factors, but it is still unclear. A systematic review study showed that the combination of alcohol consumption above recommended limits and overweight/obesity may be associated with a significantly increased risk of chronic liver disease. And this study reported that this risk increases with a BMI (body mass index) greater than 25 and alcohol consumption greater than 14 units/112g per week (6), which is equivalent to 8 drinks with 14g of pure alcohol in the Brazilian context.
The relationship between alcohol consumption and overweight/obesity still needs to be better studied. However, despite the limitations of current studies, it is reasonable to say that alcohol intake associated with obesity/overweight may be a risk factor for other diseases, probably due to many lifestyle factors. In this way, moderation in alcohol consumption is an important recommendation, along with a balanced diet and a healthy lifestyle.
