To find out, identical twins, doctors Chris and Alexander van Tulleken, embarked on an unusual experiment. One gave up fats, the other sugar. The results were surprising and reveal more than one might think.

Brothers with the same genes but different dietary approaches

Chris and Alexander shared more than just genes - both are doctors, have similar lifestyles and dietary preferences. However, Chris gained more weight than Alexander while in the USA. This prompted them to investigate the impact of diet on body weight.

Within the framework of a BBC program, they decided on an experiment: Alexander eliminated almost all carbohydrates (sugars) from his diet, while Chris eliminated almost all fats. Each ate according to their desires, without quantity restrictions, with only one prohibition - sugars for Alexander, fats for Chris.

Firsthand experiences: sugar vs. fat

Alexander, on a sugar-free diet, could enjoy meat, fish, eggs, and cheese. However, he reported a lack of energy, tiredness, and unpleasant breath. In one month, he lost 6 kilograms but did not feel his best.

Chris, who ate a fat-free diet, constantly felt hungry and often reached for snacks. Food without fats did not provide him with satisfaction, yet he lost 2 kilograms.

Scientific perspective: what do studies say?

Research shows that both low-carb and low-fat diets can lead to weight loss. A 2018 Stanford University study showed that there is no significant difference in weight loss between the two diets. The individual's ability to adhere to the chosen diet is a more important factor.

Another study showed that women with insulin resistance on a low-carb diet lost more weight than those on a low-fat diet. This indicates that an individual's health condition can affect the effectiveness of a particular diet.

The combination of sugar and fat: a dangerous trap

The van Tulleken brothers found that it's not just sugar or fat that causes issues, but their combination. Foods containing both - such as chocolate, ice cream, and fries - strongly affect the brain's reward centers, which can lead to overeating.

The modern food industry often combines sugar and fat, as this combination stimulates appetite and increases food cravings. This can lead to increased body weight and health problems.

Balance and moderation are key

Instead of focusing on eliminating one group of nutrients, it is important to seek balance. A healthy diet includes moderate consumption of all macronutrients - carbohydrates, fats, and proteins - with an emphasis on unprocessed foods.

It is also important to listen to your body and avoid processed foods that combine sugar and fat. Such foods can affect our eating habits and health.