The Fat’s on Fire: Curbing Obesity in Japan

by Nandini Jayarajan

In 2008, Japan’s Ministry of Health passed the ‘metabo’ law and declared war against obesity by measuring the country’s waistline. Their intent is to curb the rise of metabolic syndrome, a number of factors that lead to diabetes and cardiovascular disease including obesity, high blood pressure, high glucose levels and cholesterol. By keeping metabolic syndrome in check, the government hopes to stall the ballooning health care costs of their aging population.

In recent decades, concerns over rising rates of obesity and related metabolic diseases in developing countries have increased. Many of these countries are witnessing a growing aging population with decreasing birth rates, foreshadowing a costly future for health systems faced with supporting the declining elderly without the backing of a youthful workforce. Management of chronic disease such as diabetes, hypertension and other metabolic syndromes will compound these costs. Globally, current health policy is being re-examined and interventions to reduce the incidence of metabolic disease in the coming years are being implemented, but none are more radical than Japan’s ‘metabo law’, a law that requires men to maintain a waist line less than 33.5 inches and women less than 35.4 inches.

Obesity in Japan - a rising epidemic.

Obesity in Japan - a rising epidemic.

Japanese people are normally envied for their lean physiques. In fact, the Organization for Economic Co-operation and Development (OECD) ranks them, with only 3% population obesity, one of the least obese developed countries. So it comes as a surprise to many that obesity has become such a large issue in this society. The country’s concerns, however, are not unfounded as average body mass index (BMI) has increased over the past 40 years. In 1994 the estimated prevalence of *CensureBlock* obesity (BMI >30) was 2.1% and 3.1% in men and women respectively, and 2.8% and 3.5% in men and women respectively in 2003[i]. The obesity trend in children also showed a remarkable increase. Comparing the time periods 1976-1980 and 1996-2000, prevalence of obese boys and girls increased from 6.1% and 7.1% to 11.1% and 10.2%. Though the prevalence is much lower than countries like the U.S., the Japanese government found this trajectory concerning enough to mitigate its progression by imposing regulations.

Obesity has been linked with developing metabolic syndromes such as diabetes, and hypertension, which later lead to cardiovascular disease and other complications. Specifically, fat mass collected in the upper body is suggested to be the culprit and the main reason for Japan targeting the population’s waist lengths[ii]. Studies show that Asians become susceptible to metabolic syndromes at a lower waist size than Caucasians. The International Diabetes Federation reports that diabetes is seen to develop at waist circumferences above 94 cm and 80 cm European and U.S. men and women compared to 90 cm and 80 cm for Japanese men and women, and as obesity rises the incidence of metabolic syndromes are also seen to be rising[iii]. Between 1960 and 2003, nation wide surveys showed that serum total cholesterol levels had increased by 10-35 mg/dL, and the prevalence of hypertension went from 8.0 per 1,000 people in 1965 to 15.6 per 1,000 in 1975, and 30.7 per 1,000 in 2003.

The leading explanation for this increase is attributed to changes in diet and physical exercise. It has been noted that increased economic prosperity leads to a nutrition transition of a diet high in total fat, cholesterol, sugar, and other refined carbohydrates and low in polyunsaturated fatty acids and fiber, which combined with decreased dependence on manual labor force resulting in an increasingly sedentary lifestyle increases the prevalence of obesity and its associated diseases. This trend has been especially true for Japan. Since WWII, increased prosperity has been accompanied by increased energy intake. Daily per capita consumption of animal products increased by 257g, daily per capita total fat consumption increased 341%, and the proportion of energy from fat increased from 8.7% to 24.8%[iv].  Larger household incomes meant access to a more varied diet. Consumption of rice in the daily diet decreased being replaced by bread, meat, and dairy products.  Use of electronic appliances and industrially prepared food drastically reduced intake of fresh food at home. Finally, the popularity of the American lifestyle led to hamburgers, French fries, milkshakes and donuts permeating the daily diet, a change further exacerbated by the introduction of the American fast food industry in the 1970’s[v]. Though Japanese diet still includes much more marine fish containing omega-3 fatty acids thought to protect against coronary heart disease, and much less food high in saturated fat than U.S., the adoption of a more ‘western diet’ is resulting in similar health

The Japanese health care system provides universal coverage primarily through local government or employer insurance, and the system is foreseeing dire financial trouble. Japanese people enjoy a high life expectancy of around 80 years, though in recent years their growth rate has slowed to a rate of 1.2[vi]. As the population ages and begins to deteriorate, the workforce will not be large enough to cover the health costs. Chronic diseases like diabetes and hypertension will further tax the system, and the government sees an opportunity in cost cutting by curbing the rising rates of obesity. A healthier, younger population today will result in a healthier, and hopefully cheaper, older population tomorrow.

To secure this, Japan’s Ministry of Health passed the Standard Concerning Implementation Special Health Examinations and Special Public Health Guidance, MINISTRY OF HEALTH, LABOR, AND WELFARE Order 159, or more commonly known as The Metabo Law. The law mandates that local governments and employers add a waist measurement test to the annual mandatory check up of 40-75 year olds. For men and women who fail the test and exceed the maximum allowed waist length of 33.5 and 35.4 inches, they are required to attend a combination of counseling sessions, monitoring through phone and email correspondence, and motivational support depending on the severity of their condition[vii].

Non-compliance has no individual consequence. The responsibility of adherence to the program falls to employers or local government. These providers are required to ensure a minimum of 65% participation, with an overall goal to cut the country’s obesity rates by 25% by year 2015. Failure to meet these goals results in fines of almost 10% of current health payments[viii].

There have been cultural consequences to the law. In an effort to pass the waist measurement test, individuals have been unloading their money on expensive fitness equipment, herbal weight loss pills, and gym memberships. Then there’s the humiliation with the exam itself, though the government has recently allowed individuals opt to keep their shirts on while being measured[ix]. Projected long-term effects could include censure on individuals unable to comply, especially in the workplace, leading to difficulties in finding employment in companies looking to avoid potential fines.

The passing of the Metabo Law also raises the issue of how much regulation is too much regulation? The Lancet recently published a study that found that due to lowered body mass index from pre-pregnancy dieting and aggressive management against weight during pregnancy has led to reduced birth weight by more that 150 g. Studies have shown that low birth weight is associated with greater susceptibility to obesity later in life[x]. Should the Japanese government then draft policy and pass laws that regulate women’s diet during their reproductive years?

If the Metabo law is successful what will be the policy impact on other countries facing similar problems? So far the U.S. has directed its policy toward industries rather than the individual with its attempts on taxing soda and sugar. Most of us probably feel secure that our political climate would never allow such a law to pass, but if proposed in a U.S culturally sensitive way would some form of regulation be possible and how bad or good would those consequences be? These considerations are important as our own health care costs sky rocket and we look to government and policy for solutions.

[i] Adrianne Bendich and Richard J. Deckelbaum, Preventive Nutrition: The Comprehensive Guide for Health Professionals (Springer, 2009).


[ii] Scott M. Grundy, “Obesity, Metabolic Syndrome, and Cardiovascular Disease,” J Clin Endocrinol Metab 89, no. 6 (June 1, 2004): 2595-2600,

[iii] “International Diabetes Federation | IDF,”

[iv] Richard D. Semba and Martin W. Bloem, Nutrition and Health in Developing Countries, Second. (Humana Press, 2008).

[v] Katarzyna J. Cwiertka, Modern Japanese Cuisine: Food, Power and National Identity (Reaktion Books, 2007).

[vi] “International Data Base – Japan – U.S. Census Bureau,”

[vii] B. T Oda, “An Alternative Perspective to Battling The Bulge: The Social and Legal Fallout of Japan’s Anti-Obesity Legislation,” Asian-Pacific L. & Pol’y J. 12 (2010): 249–330.

[viii] Ibid.

[ix] David Nakamura, “Fat in Japan? You’re breaking the law.,” June 16, 2010,

[x] Peter D Gluckman et al., “Low birthweight and subsequent obesity in Japan,” The Lancet 369, no. 9567 (March 31, 2007): 1081-1082,