While many people still believe that diet drinks can help them to lose weight because they contain no sugar or calories, a new study, which was published in the International Journal of Obesity, has just proven the opposite.
Scientists have just exposed a chemical in diet drinks, such as Diet Coke and Sprite Zero, that stimulates appetite and can cause weight gain, not loss. While it is true that diet drinks contain less or no sugar than ordinary drinks and often have zero calories, the overall effect seems to be much worse for your health.
How do diet drinks make you fat?
A previous study conducted by a team at Karolinska Institute in Sweden found that just two glasses of diet drinks per day could double a person’s risk of developing Type 2 diabetes because it makes people unnaturally hungry, causing them to overeat.
This finding led a new group of scientists in Singapore to study the effect of diet drinks and non-nutritive sweeteners on weight and size. A group of volunteers, varying in age, sex, and weight, were given four doses of aspartame instead of sugar per day, which is an artificial sweetener found in diet drinks like Diet Coke and Sprite. It was expected that all participants would lose some weight but surprisingly not a single person lost any weight: they all stayed the same weight and size.
Dr. Siew Ling Tey from the Agency for Science, Technology and Research in Singapore and one of the lead authors of the study, said that the results were surprising because they expected at least marginal weight loss in all participants.
“The energy saved from replacing sugar with non-nutritive sweetener was fully compensated for at subsequent meals in the current study, hence no difference in total daily energy intake was found between the four treatments,” he said.
A follow-up study was conducted, involving 30 randomly picked men who were given 500ml diet drinks and were then allowed to eat as much fried rice for lunch as they desired. It was found that they ate up to 80 calories more than usual at lunchtime and that they were hungrier for the rest of the day as well. While they did not binge eat, their appetites were more stimulated on diet drinks than on ordinary sugary drinks, which demonstrated the same effect of compensating for the “saved calories” from sugar-free drinks.
“One of the concerns with non-nutritive sweetener consumption is that it increases appetite, which could lead to overcompensation for the energy saved,” researchers said.
However, studies have not yet shown that it leads to any overcompensation but rather causes people to eat the saved calories from choosing diet drinks.
What about blood sugar?
There is conflicting research about the effect of diet drinks on blood sugar because while it may protect consumers from blood sugar spikes and empty calories, the after- effect seems to be equally risky. People who choose to drink diet drinks tend to eat more afterward, which can cause higher blood sugar levels than simply consuming a sugary drink.
So far, animal studies have shown that aspartame and other non-nutritive sweeteners cause an increase in the absorption of glucose, which is a risk for the development of obesity and Type 2 diabetes.
Gavin Partington, the director-general of the British Soft Drinks Association, concludes: “Decades of scientific research has shown that low-calorie sweeteners, such as those found in diet drinks, help consumers to manage their weight as part of a calorie-controlled diet.” The key is to watch what you eat after consuming diet drinks, though.