Scientists Reveal Why Bread Can Cause Weight Gain Without Overeating17 April 2026 ByDavid Nield (Photographer Basak Gurbuz Derman/Moment/Getty Images) New research in mice shows how eating bread can cause body weight and fat mass to increase, even though caloric intake stays at a similar level. The research, led by a team from Osaka Metropolitan University in Japan, highlights how carbohydrates can contribute to weight gain as well as excessive fat intake – which is what dietary advice tends to focus on. This isn't the first time nutritionists have talked about bread and carbohydrates and their contribution to weight gain, but there hasn't been much detailed research into the relationship – especially wheat flour – or into what might be happening at a metabolic level. The team discovered that eating more wheat bread was associated with reduced energy expenditure, pushing the metabolism towards a state where fat storage is prioritized, even when the calories in a diet stay at a similar level. The researchers analyzed the difference that bread in the diets of mice had on their weight (A) and fat tissue (B, C). (Matsumura et al., Mol. Nutr. Food Res., 2026) "These findings suggest that weight gain may not be due to wheat-specific effects, but rather to a strong preference for carbohydrates and the associated metabolic changes," says nutritionist Shigenobu Matsumura of Osaka Metropolitan University. The researchers set up experiments in which lab mice were given a choice between their normal, healthy cereal-based diet and either simple bread, baked wheat flour, or baked rice flour. The mice were then monitored to check their weight and how their bodies burned calories at rest and when active. Using blood samples, the study team also examined hormone, blood sugar, and metabolite levels in the animals, while post-experiment tissue analyses assessed gene expression in the liver. The experiments showed that the mice strongly preferred to switch from their standard diet to carbohydrate-heavy snacks, which then led to weight gain and more fat tissue in the mice, particularly in the males. Further analysis and follow-up tests suggested that these two key changes were being driven not by overeating or a lack of exercise, but by the foods themselves. In the wheat flour diet, fewer calories were being burned overall, while genes responsible for turning carbohydrates into fat were activated. Another follow-up test focusing on the wheat flour group showed that when the chow diet was restored, the weight gain stopped, and the metabolic shifts were reversed. "In the future, we hope this will serve as a scientific foundation for achieving a balance between 'taste' and 'health' in the fields of nutritional guidance, food education, and food development," says Matsumura. The findings are more evidence of how what we eat can cause changes in how our body processes food and burns the calories it contains. In the case of bread, it seems to slow down the body's metabolic engine. One limitation of the study is that it used mouse models, rather than human volunteers. While it's likely that similar processes are happening in people, it's not certain – so that's something future studies can pick up. The researchers also want to experiment with a broader selection of foods to identify what exactly it is about bread that causes this reaction. No diet study like this exists in isolation, of course. We know that a variety of other factors can also impact how our metabolism reacts to food and drink, including age and hormone-related changes. Related: There's a Surprising Link Between a Key Nutrient, Obesity, And Alzheimer's Risk Further research should help establish the role that wheat and bread can play in a diet and how the simple "calories in, calories out" rule isn't always straightforward. "Going forward, we plan to shift our research focus to humans to verify the extent to which the metabolic changes identified in this study apply to actual dietary habits," says Matsumura. "We also intend to investigate how factors such as whole grains, unrefined grains, and foods rich in dietary fiber, as well as their combinations with proteins and fats, food processing methods, and timing of consumption, affect metabolic responses to carbohydrate intake." The research has been published in Molecular Nutrition & Food Research. ARTICLE SOURCE: https://www.sciencealert.com/scientists-reveal-why-bread-can-cause-weight-gain-without-overeating
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Enjoyed the video. I was working so I didn't get to participate. Maybe next week.
Couple good points about supplements and dairy. I drink milk on occasion and use a whey protein supplement.
The dairy is just like mentioned in the video, very individualistic. I do fine and have no issues. When I was losing some of the weight, I did have stalls and over time I linked the stalls to the milk. When weight loss was still a goal the milk was limited for me. I'm down somewhere between 90-95 pounds and drink a couple glasses a week, or so. Milk was designed to make us grow, and that it will. As babies and toddlers, it makes us grow up and as adults is can make up grow out, if that makes any sense at all.
I struggle to eat enough protein to hit the target for hypertrophy. I'm amazed at how much others can eat, not only per meal but per day. It is a struggle for me to eat 200 grams of protein (1 gram per pound of ideal lean body mass). If I eat a 14-16oz. steak with a couple thee eggs I am stuffed and that full feeling lasts for ~24 hours or so, somedays even longer. In order to hit the target, I have to eat another meal that I do not really want, which is another carnivore irony in itself. Prior to carnivore I could eat a 14-16oz steak with a couple-three eggs three times per day and do a desert with 4-5 Mountain Dews during the day. I suppose it was all the carbs and sugars, cravings and maybe even addictions, that was telling me to eat/telling me I was hungry. I simply don't feel comfortable eating large amounts of food. I sort of 'protein cheat' with a protein drink.
For me, this is working. I dropped 95lbs in 13 months. I have had some muscle growth but am much stronger (more plates).
Good video. I hate I missed participating.
Scott