Health Benefits Not Visible on the Scale: A 10% Reduction in Visceral Fat Can Change Diabetes Risk

When measuring the success of a diet, many people first look at the numbers on the scale. How many grams have been lost since yesterday, or how many kilograms have been shed in a month. These numbers are straightforward and provide a sense of achievement. However, the latest research reiterates that what truly matters for health is not just "how many kilograms have been lost."

The focus is on "visceral fat" that accumulates deep in the abdomen, surrounding the organs. Unlike subcutaneous fat, which lies just beneath the skin, visceral fat is closely linked to metabolism, inflammation, and insulin resistance. Even people who do not appear very overweight can experience changes leading to diabetes, dyslipidemia, and hypertension if their waist circumference increases.

An article featured on a German news site discusses several studies on the reduction of abdominal fat and the associated decrease in diabetes risk. A significant point highlighted is that for every 10% reduction in visceral fat, there is a potential 28% decrease in the future risk of type 2 diabetes. Interestingly, even if body weight returns, if the waist circumference and visceral fat remain lower than their original levels, the metabolic benefits may persist.

"Rebound ≠ Failure"

One of the most disliked words in dieting is "rebound." When lost weight returns, many feel that "it was all for nothing." However, research on visceral fat challenges this perspective.

Research teams from Ben-Gurion University and Leipzig University, among others, followed participants who underwent lifestyle interventions, including diet and exercise, over long periods of 5 to 10 years. MRI scans of body fat distribution revealed that even participants whose weight fully returned still showed some improvements in visceral fat and waist circumference. This reduction in visceral fat was associated with a decreased risk of future type 2 diabetes.

This suggests that judging the success of a diet solely by whether weight has returned is simplistic. The scale only shows the total body weight and does not differentiate between muscle, subcutaneous fat, visceral fat, and water content. What matters for health is which fat has decreased and which state is maintained.

This perspective is also relevant to Japanese people. In the treatment of obesity in Japan, not only BMI but also the accumulation of visceral fat and waist circumference have been emphasized. East Asians, including Japanese, are said to be more prone to metabolic abnormalities even at relatively low BMIs compared to Westerners. Therefore, being "close to standard weight" does not necessarily mean one is safe. It is necessary to consider waist circumference, blood glucose levels, lipids, and blood pressure together.

Fasting or Calorie Restriction: The Winner Is Unclear

In recent years, intermittent fasting methods like 16-hour fasting, the 5:2 diet, and alternate-day fasting have gained popularity. On social media, there are many posts claiming "I lost weight by skipping breakfast" or "My health improved just by narrowing my eating window." Meanwhile, traditional calorie restriction, which involves gradually reducing daily energy intake, remains popular.

A study published in BMJ compared intermittent fasting with traditional calorie restriction and found no significant overall difference between the two. Although alternate-day fasting showed a slightly greater average weight loss, the difference was not considered clinically significant.

What emerges from this is that "which method is the best" is less important than "whether the method is sustainable for the individual." For those who cannot concentrate without breakfast, 16-hour fasting can be painful. Conversely, for those who naturally reduce calorie intake by simply stopping late-night snacks, time-restricted eating might be suitable.

Dieting cannot be sustained by theory alone. The ease of implementation varies depending on work, family, sleep, stress, food culture, and frequency of eating out. The message from the latest research is closer to "choose a sustainable lifestyle while monitoring waist circumference and health, rather than jumping on trendy methods."

Is Rapid Weight Loss Really Bad?

Another intriguing point of discussion is the speed of weight loss. For a long time, it has been said that "losing weight slowly is less likely to lead to rebound." Indeed, extreme dietary restrictions done on one's own can lead to muscle loss, nutritional deficiencies, and disordered eating behaviors.

However, a study presented at the European Congress on Obesity in 2026 reported that a rapid weight loss program conducted under expert supervision was superior to gradual weight loss in terms of weight reduction and achievement of treatment goals one year later. The study involved 284 adults with obesity, with the rapid weight loss group undergoing a phased low-calorie diet, followed by a program to prevent weight regain.

The key point here is not a simple statement that "it's okay to lose weight quickly." The study dealt with a structured and professionally managed weight loss program, which is different from skipping meals or imposing extreme restrictions on oneself in a short period.

On social media, there are often reactions to such studies suggesting that "short-term focus may keep motivation going." However, experts caution that "evaluation of body composition and muscle mass is necessary" and "it does not apply to everyone." The essence is not whether to lose weight quickly or slowly, but whether it can be maintained long-term without worsening blood sugar, blood pressure, and lipids while preserving muscle.

The Key to Reducing Visceral Fat Is Not "Extreme Prohibition"

When people want to reduce their waistline, they often demonize carbohydrates and fats first. Completely eliminating white rice, giving up sweets entirely, and thoroughly avoiding fats. In the short term, this may lead to weight loss, but extreme prohibition is difficult to sustain and can easily lead to rebound.

Moreover, there are studies that caution against the complete elimination of sugars. An animal study published in 2026 reported that mice fed a low-fat diet with complete exclusion of sucrose showed changes related to impaired glucose tolerance, insulin resistance, gut microbiota imbalance, inflammation, and fatty liver, even with similar body weight. While this cannot be directly applied to humans, it warns against the simplistic notion that "cutting out sugar entirely will lead to health."

The issue is not carbohydrates themselves, but how they are consumed and their quality. Reducing refined sugars, white bread, sweets, and sugary drinks is meaningful. On the other hand, carbohydrates and dietary fibers found in whole grains, legumes, vegetables, and fruits help control blood sugar spikes and contribute to satiety and gut health.

In reducing visceral fat, it is important to focus not only on "subtraction" in the diet but also on "replacement." Replace sugary drinks with water or unsweetened tea. Switch white bread to whole grain bread. Replace late-night snacks with meals containing protein and dietary fiber. Shift meals centered on fried foods to those including fish, beans, vegetables, nuts, and olive oil. These small changes can lead to noticeable changes in waist circumference.

Exercise Is Not Just About "Abs"

When concerned about their waistline, many people start doing abdominal exercises. While strengthening the abs is not bad, targeting belly fat solely through abdominal exercises is not possible. Fat is used in the overall energy balance of the body, so be cautious of claims that promise "only the belly will slim down."

For effective visceral fat reduction, combining aerobic exercise with strength training, in addition to dietary improvements, is recommended. Activities like walking, jogging, cycling, and swimming increase energy expenditure, while strength training helps maintain muscle mass. Muscles also play a role in glucose uptake, making them important from a diabetes prevention perspective.

Busy individuals do not need to start by going to the gym. Taking the stairs, walking for 10 minutes during lunch breaks, walking part of the commute, or doing squats a few times a week are all beneficial. The key is not a "perfect menu" but creating habits that can be integrated into daily life.

On Social Media, "Waist Circumference Over Scale" Resonates with Caution

Topics related to this research are shared on social media, especially among experts and users interested in health information. On LinkedIn, research participants have been introduced as having "retained visceral fat reduction even if they regained weight, which was associated with improved insulin sensitivity and cardiometabolic scores," suggesting that visceral fat should be considered a long-term success indicator rather than just body weight.

Posts by doctors and researchers highlight positive reactions, stating that "reducing visceral fat is important for long-term cardiometabolic health." Comments on a doctor's post also recognized visceral fat reduction as "an important step in reducing disease risk." On X, posts with the theme "visceral fat reduction leaves a metabolic legacy for up to 10 years" are being shared.

However, the reactions on social media are not all praise. Some researchers argue that interpreting "visceral fat is everything" is an overreach, and context should include body weight, muscle mass, diet quality, inflammation, and individual differences. This is a very important point. While visceral fat is a powerful indicator, health cannot be discussed based on a single number.

For general readers, this balance is necessary. Instead of taking an extreme view that "you don't need to worry about weight," it is more realistic to think "don't get too caught up in just the weight." Consider multiple indicators like waist circumference, blood tests, physical fitness, sleep, diet, and muscle mass to truly understand changes in your body.

Practical Points for Japanese People

In Japan, there are many opportunities to measure waist circumference during health checkups. The criteria of 85 cm or more for men and 90 cm or more for women are known as indicators of visceral fat accumulation. However, these numbers are merely a starting point and should be considered alongside individual body composition and blood test results.

To incorporate this research into daily life, the following approach is effective.

First, measure not only weight but also waist circumference regularly. It doesn't have to be daily. Even measuring once or twice a month under the same conditions can make changes more noticeable.

Next, in terms of diet, think about "what to replace" rather than "what to completely stop." Reduce sugary drinks, sweets, late-night snacks, and refined carbohydrates, and increase protein, vegetables, seaweed, legumes, and whole grains.

Then, incorporate both aerobic exercise and strength training gradually. Trying to change dramatically in a short period can lead to setbacks. Starting with a 10-minute walk a day or light strength training at home is fine.

Finally, do not underestimate sleep and stress. Lack of sleep and chronic stress affect appetite and blood sugar control and are related to the accumulation of abdominal fat. A healthy waistline is not created by dietary restrictions alone.

Conclusion: Focus on "Content" Rather Than "Lightness"

The figure that a 10% reduction in visceral fat can potentially lower diabetes risk by 28% is very impressive. However, it is dangerous to isolate this figure and think, "If I do this, I can definitely prevent diabetes." What the research indicates is that reducing visceral fat through lifestyle changes may be deeply connected to long-term metabolic health.

Dieting is not a competition to make the body smaller. More important than reducing the numbers on the scale is achieving stable blood sugar, improved waist circumference, preserved muscle, and a lifestyle that can be sustained long-term.

Even if there is a rebound, not everything is wasted. Traces of good lifestyle habits may remain in the body. With this perspective, even a walk for one station, choosing to increase vegetables at dinner, or avoiding a sugary drink once has meaning.

Do not be overly swayed by the numbers on the scale; instead, focus on waist circumference and lifestyle habits. The new hint for diabetes prevention lies there.

Source URL

Overview article by ad-hoc-news on intermittent fasting, rapid weight loss, visceral fat reduction, and diabetes risk
https://www.ad-hoc-news.de/wissenschaft/bauchfett-reduktion-10-percent-weniger-senkt-diabetes-risiko-um-28/69568076

Original paper on 10% visceral fat reduction and type 2 diabetes risk reduction: Long-term follow-up study published in Circulation
https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.125.079009

Overview of the same study: EurekAlert article by Ben-Gurion University
https://www.eurekalert.org/news-releases/1131678

Explanation of the same study: Article by Harvard T.H. Chan School of Public Health on visceral fat and long-term metabolic and cognitive health
https://hsph.harvard.edu/news/visceral-fat-loss-associated-with-better-long-term-cardiometabolic-cognitive-health/

Comparison of intermittent fasting and traditional calorie restriction: Systematic review/network meta-analysis published in BMJ
https://www.bmj.com/content/389/bmj-2024-082007

Comparison of rapid and gradual weight loss: EurekAlert article on research presented at the European Congress on Obesity 2026
https://www.eurekalert.org/news-releases/1128299

Expert comments on rapid weight loss research: Summary of opinions by Science Media Centre
https://www.sciencemediacentre.org/expert-reaction-to-un-published-eco-2026-abstract-on-rapid-versus-gradual-weight-loss-for-reducing-risk-of-obesity-related-complications/

Introduction of animal experiments on complete sugar elimination: Article by ScienceDaily
https://www.sciencedaily.com/releases/2026/06/260614011843.htm

Explanation of Japanese obesity and visceral fat standards: Endocrine Journal article summarizing concepts from the Japan Society for the Study of Obesity guidelines
https://www.jstage.jst.go.jp/article/endocrj/71/3/71_EJ23-0593/_html/-char/en

Example of SNS reaction: LinkedIn post by Luigi Fontana recognizing the importance of visceral fat reduction while emphasizing the need for context in interpretation
https://www.linkedin.com/posts/lfontana69mdphd_longevity-metabolism-visceralfat-activity-7469538711525916672-m4QG

Example of SNS reaction: LinkedIn post by Anat Yaskolka Meir advocating for viewing visceral fat as a long-term success indicator rather than just body weight
https://www.linkedin.com/posts/anat-yaskolka-meir-29aa7450_lifestyle-induced-visceral-fat-loss-as-a-activity-7467535493761572864-zh8s

Example of SNS reaction: LinkedIn post by Dr. Christopher Cannon mentioning the benefits of visceral fat reduction on long-term cardiometabolic health
https://www.linkedin.com/posts/ch