Unhealthy rewards? Diet drinkers may ‘compensate’ by eating more unhealthy food

People who drink diet beverages may compensate for the absence of calories in the drinks by feasting on extra food that is loaded with high levels of sugar, salt and unhealthy fats, say researchers.

The suggestions come after a team of US-based researchers followed the dietary habits of 22,000 people over a ten year period – and found that those who consume more diet beverages, also seem to consume a higher level of ‘discretionary foods’ - which includes foods that do not belong to the major food groups and are not required by the human body but may add variety to a person's diet.

"It may be that people who consume diet beverages feel justified in eating more, so they reach for a muffin or a bag of chips," commented lead researcher Professor Ruopeng An, from the University of Illinois. "Or perhaps, in order to feel satisfied, they feel compelled to eat more of these high-calorie foods."

Writing in the Journal of the Academy of Nutrition and Dietetics, An and his team found that 90% of the participants in the study consumed energy-dense, nutrient-poor ‘discretionary foods’ – like cookies, ice cream, chocolate, fries and pastries – every day, averaging about 482 calories per day from these products.

The team then looked at how often people drank different beverages, and split them in to groups accordingly. They found that while coffee and diet-beverage drinkers consumed fewer total calories each day than people who preferred alcohol or sugary drinks, they obtained a greater percentage of their daily calorie intake from discretionary foods. An commented that such a finding that suggests a possible compensation effect.

Study details

An and his colleagues examined 10 years of data from the National Health and Nutrition Examination Survey, which asked participants to recall everything they ate or drank over the course of two non-consecutive days. 

They then analysed participants' daily calorie intakes, including their consumption of discretionary foods and five types of beverages - diet or sugar-free drinks; sugar-sweetened beverages, such as sodas and fruit drinks; coffee; tea; and alcohol.

More than 90% of people in the study consumed discretionary foods daily, averaging about 482 calories from these products each day, reported An and his team – who also found that 97% of the study population consumed at least one of the five types of beverages daily, and around 41% drinking beverages from at least two of the categories.

According to the data, coffee was participants' beverage of choice and was consumed by more than half (53%) of the population, followed by sugar -sweetened beverages (43%), tea (26%), alcohol (22%) and diet beverages (21%).

Alcohol consumption was associated with the largest increase in daily calorie intake (384 calories), followed by sugar-sweetened beverages (226 calories), coffee (108 calories), diet beverages (69 calories) and tea (64 calories). 

However, the team noted that while the overall increase in calorie consumption may be small, those who consumed diet drinks and coffee had a comparatively higher proportion of daily calories from snacking and eating unhealthy food options in the ‘discretionary foods’ category.