Latest news with #yoyodieting
Yahoo
20-07-2025
- Health
- Yahoo
Scientists Find Evidence of Grim Long-Term Effects of Fad Diets
The way Westerners diet — often alternating dubious and restrictive food regimens with binge eating, in a phenomenon known as "yo-yo dieting" — may be messing with their gut flora and their brains. In a new study published in the journal Advanced Science, researchers from France's University of Rennes and Paris-Saclay University found, after conducting a series of studies with mice, that yo-yo diets appeared to result in long-lasting changes to their gut bacteria. Also known as "weight cycling," this form of dieting often involves people taking on restrictive — and often extreme or trendy — plans to lose weight, only to get so hungry from such the vast and unsustainable change in their habits that when they go back to the way they ate before, they end up eating too much, and gaining back all the weight and then some. While it's well known that yo-yo dieting is a bad idea compared to making sustainable choices to eat healthier foods, recent studies have begun to show its links to other detrimental health effects, including increased risk of kidney and heart disease and hormonal changes that can slow down the metabolism. In their new study, the researchers from Rennes and Paris-Saclay simulated human yo-yo dieting by alternately feeding mice a higher-fat and higher-sugar diet reminiscent of those eaten by the modern Westerner and one that was lower fat, over a period of several weeks. When they were switched back onto the richer diet, the mice started showing signs of binge eating. Not only was this effect seen in the mice who were subjected to the yo-yo diets, but also to rodents who had eaten healthier food but were implanted with "altered" gut bacteria from the other mice. Curiously, the French researchers also found that shifts in the rodents' diets appeared to change their relationship to food as well, adding to the body of evidence that fad diets and the yo-yo effect they instill could be considered a form of disordered eating. "By carefully analysing the brain patterns of the mice on the dieting schedule, the researchers could see that they were probably eating for pleasure rather than because they were hungry," a press release about the study notes, "as if the brain's reward mechanism had been rewired." While it's far too soon to tell whether that effect will be replicable in humans, anyone who's experienced the yo-yo dieting effect personally can attest that that first bite of a burger or fries after going weeks without is indeed very, very satisfying. More on mice studies: Scientists Gene Hack Mice So Their Livers Produce Their Own Ozempic-Like Drug Solve the daily Crossword
Daily Mail
04-06-2025
- Business
- Daily Mail
Common diet Brits choose to lose weight could lead to depression, study finds
Yo-yo dieting which is used by many Brits to lose weight could lead to depression, a study has found. The diet involves managing calories to shed the pounds before putting the weight back on again. And researchers have discovered questionnaire scores for depressive symptoms, such as a low mood, low energy and sleep disturbances, were higher among those restricting calories using such diets, compared to those who reported not being on one at all. The scores were also higher among overweight people following low-calorie diets. The effects of calorie restriction on mood were more pronounced in men and overweight people, the study said. The findings contrast previous reports which claim low-calorie diets improve depressive symptoms. However, researchers argued prior trials included tailored and balanced diet programmes that may not be the same as what people realistically follow in everyday life. The team said a focus on 'idealised diets' can 'overlook the diversity of dietary patterns'. For the study, published in BMJ Nutrition Prevention & Health, researchers in Canada used data from the 28,525 people who took part in the US National Health and Nutrition Examination Survey (NHANES) and had completed a health questionnaire relating to depressive symptoms, which gave them a score based on severity. A little under 8 per cent had reported depressive symptoms, while 33 per cent were overweight and 38 per cent were obese. The majority of the group (87 per cent) said they were not on a specific diet, while 2,206 (7.7 per cent) were restricting calories. Some 859 (3 per cent) were on a 'nutrient-restrictive' diet, low in fat, sugar, salt, fibre or carbohydrate, and 631 (2.2 per cent) were on diets tailored for the likes of diabetes. Researchers found low-calorie diets were more common among obese patients and those who were overweight. They said: 'Numerous studies have consistently focussed on "healthy" versus "unhealthy" diets. 'They have shown that "healthy" diets rich in minimally processed foods, fresh fruits and vegetables, whole grains, nuts, seeds, lean proteins and fish have been linked to a lower risk of depression. 'In contrast, an "unhealthy" diet dominated by ultra-processed foods, refined carbohydrates, saturated fats, processed meats and sweets is associated with an increased risk of depressive symptoms. 'Therefore, individuals must adopt a perfectly healthy dietary pattern to reduce the risk of depressive symptoms. This dichotomy fails to capture the complexity of real-world eating habits.' Restricting calories can lead to deficiencies in protein, vitamins and minerals, researchers suggest, which puts the body under stress. They added: 'In contrast, real-life calorie-restricted diets and obesity often result in nutritional deficiencies, particularly in protein, essential vitamins and minerals, and induce physiological stress, which can exacerbate depressive symptomatology including cognitive-affective symptoms.' Researchers stressed the study has a number of limitations, but gives an insight to how diets recommended by healthcare professionals should be considered for risk factors for depression, especially in men and obese patients. Professor Sumantra Ray, chief scientist at the NNEdPro Global Institute for Food, Nutrition and Health, added: 'This study adds to the emerging evidence linking dietary patterns and mental health, raising important questions about whether restrictive diets which are low in nutrients considered beneficial for cognitive health, such as omega-3 fatty acids and vitamin B12, may precipitate depressive symptoms. 'But the effect sizes are small, with further statistical limitations limiting the generalisability of the findings.
