Is alcohol sabotaging your diet?

A new study from Penn Nursing suggests that, if you want to lose weight and keep it off, you might want to think about cutting back on drinking.

The study, which was led by Ariana Chao, an assistant professor of nursing who studies obesity treatment and binge eating, examined how drinking affected weight loss among 4,901 people with Type 2 diabetes who participated in the Action for Health in Diabetes study.

That study compared weight loss for people who underwent an intensive lifestyle intervention that focused on improving diet and exercise with those in a control group.

The people in the intervention group were told about the calories in alcohol and advised to decrease drinking to reduce caloric intake. On average, people in the intervention group lost considerably more weight during the first year (around 9 per cent of total weight) than those in the control group, who lost less than 1 per cent of body weight.

During the first year, drinking level didn’t affect weight loss. Nor did people in either group actually reduce their drinking. However, non-drinkers in the intervention group had kept more weight off at four years — 5.1 per cent of initial weight — than those who drank at any level. Heavy drinkers, defined as men who drank more than 14 drinks a week or women who drank more than seven, had lost 2.4 per cent of initial weight at four years.

Alcohol abstainers were also considerably more likely to lose 10 per cent or more of their weight. Twenty-seven per cent of non-drinkers attained that goal compared with just 4.8 per cent of heavy drinkers. Twenty-four per cent of light drinkers lost 10 per cent or more of their body weight.

From a health standpoint, losing 5 per cent or more of your weight can improve your health even if you’re still overweight, Chao said.

People in the study were 45 to 76 years old and less likely to drink than the general population. At the beginning of the study, 38 per cent said they had not had a drink in the past year. (Nationally, about 70 per cent of Americans say they drink at least once a year.) Only 1.7 per cent of study participants said they were heavy drinkers.

One limitation of the study, Chao said, is that people tend to underestimate their drinking.

Drinking may undercut diets in several ways, Chao said. One is that alcoholic drinks tend to be extra calories. People add them to meals rather than, say, substituting them for a side dish. The calories can be substantial. According to the National Institutes of Health, 12 ounces of regular beer has 153 calories. Craft beer, which often has higher alcohol content, can have more.

Five ounces of white wine has 121 calories. Red has 125 calories. Sweet mixed drinks are where the calories can soar. A 4.4-ounce margarita has 168 calories and a 9.9-ounce piña colada has 490 calories. But keep in mind that many restaurant drinks are bigger than this.

Beyond the calories, studies have shown that people who are drinking tend to eat more and make poorer choices about food when they’re drinking.