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
Hello everyone. I'd like to ask for your attention and help/advice regarding how to follow a Carnivore Diet when you have financial restrictions.
I followed a carnivore diet for 12 months. I wasn't very successful in my weight loss goal. I lost around 15 pounds of fat. (I still have at least another 15 pounds). I am around 22% Bodyfat and my goal is to be under 15BF%
After the 12-month period, I ended up trying a more ketogenic model, but without success in terms of fat loss.
I'm Brazilian and live in São Paulo. Red meat prices have risen considerably. Therefore, I'd like to ask how to follow the Carnivore Diet if I can only afford eggs and hamburger patties.
I'm 180cm tall. My bodyweight is around 175-180 lbs(+- 79kg to 81kgs). I am 36 years old, have a sedentary job. I go to the gym (where I do perform resistance strength training) 3 times a week.(to build and mantain musle mass and improve fat loss) My goal is to lose 12-15 pounds of bodyfat.(until the end of 2025)
I don't know how to calculate how much food I should eat on a Carnivore diet based on eggs and Hamburger patties. (I'll leave some questions here about how to proceed :)
100 grams of Hamburger patties contain:
Calories = 135 kcal
Carbs: 2g
Protein = 11g
Fat = 9g
I man at my size and phisical activive usually ingest 2500kcals to mantain his weight. However, in a Carnivore diet most people dont control calories and sometimes even macros. I tried last year to eat to satiety but after the initial 100 days i was not able to lose bodyfat.
Allow now to aks a few question about how to set a carnivore diet , with the purpose of fat loss while only being able to buy lard, Eggs and Humburger patties(hard financial restrition):
1-How can I figure out how much food (and calories) I should eat to lose weight?
2-Should I count calories or follow the eating-to-satiety model, even if it hasn't worked for fat loss? (not after the initial 100 days of the Carnivore diet).
3-How do I deal with hunger when eating a carnivore diet with the goal of fat loss?
4-Would it be possible to lose 12-15 lbs by the end of this year without going hungry?
Thank you very much for your attention.
Excuse any grammatical errors. English is not my first language.
I look forward to your guidance.