A new analysis shows that what we eat plays a much greater role in obesity than how much we exercise.

Many industrialized countries have a problem with obesity – and according to a study, this may be primarily due to many people's excessive calorie intake. This is the conclusion reached by a team from Duke University in Durham, USA, in a review study published in the journal "Proceedings of the National Academy of Sciences."

It's clear that people become overweight when they consume more calories than they burn, the authors write. However, it has been unclear until now whether so many people are overweight because they consume too many calories or expend too little energy, meaning they don't exercise enough.

The study comes to a clear conclusion: increased energy intake plays a role in the obesity crisis about ten times as important as energy consumption.

The researchers reached this conclusion by analyzing data on body mass index (BMI), body fat percentage, and energy expenditure from 4,213 people from 34 population groups on six continents. The team included diverse groups with very different lifestyles, including hunter-gatherers, farmers, and people from industrialized countries.

Not surprisingly, a correlation was found between living in economically developed countries and a higher BMI and body fat percentage – however, energy expenditure was also higher in these groups. This shows that widespread obesity in industrialized countries cannot be explained by people simply not getting enough exercise.

The research team suspects that the cause is a much higher consumption of highly processed foods, which are particularly common in industrialized countries. These include sausages, sweets, and convenience foods. According to the study, higher body fat percentages were found in places where such foods are common. This could be because the wide availability and low cost of these foods encourage excessive consumption.

Although the authors did not have detailed information on the dietary habits of the groups studied, they nevertheless suggest that diet appears to play an important role in industrialized countries. The findings provide important information for drawing conclusions, for example, with regard to health policy.

Many Western countries are struggling with obesity as a widespread disease: According to the German Obesity Society, around two-thirds of men and just over half of women in Germany are overweight. The problem has become significantly more severe globally in recent decades, including among children and adolescents. This is associated with a higher risk of disease and health problems.