Module 4: Overnutrition

By 2020, an estimated two-thirds of the global burden of disease will be caused by chronic non-communicable diseases, most of which are associated with diet.(1) However, while hunger is a tremendous global health concern that cannot be minimized, overnutrition should similarly be addressed as a top priority. The global prevalence of malnutrition and undernutrition is devastatingly high: one billion people are adversely affected by malnutrition.(2) Moreover, people who are overweight may be malnourished. The World Health Organization (WHO) refers to this as the “double burden of malnutrition” which is characterized by “the coexistence of undernutrition along with overweight and obesity, or diet-related noncommunicable diseases, within individuals, households and populations, and across the lifecourse.”(3) In fact, in 2014 the WHO estimated that worldwide more than 1.9 billion adults, 18 years and older, were overweight and more than 600 million adults were obese, while 42 million children under the age of five were overweight or obese.(4) Moreover, the rate of childhood overweight and obesity is rising 30% faster than in high-income countries.(5) In 2018, the WHO noted that childhood obesity is one of the most serious public health challenges, affecting people in every country in the world.(6) Globally, the problem is not the availability of food resources, but the allocation of food.


Overnutrition is defined as the overconsumption of nutrients and food to the point at which health is adversely affected.(7) Overnutrition can develop into obesity, which increases the risk of serious health conditions, including cardiovascular disease, hypertension, cancer, and type-2 diabetes.

Until recently, overnutrition had been viewed as a problem that only affected developed nations. However, overnutrition is a growing problem worldwide. The World Health Organization (WHO) describes the problem: “In the poorest countries, even though infectious diseases and undernutrition dominate their current disease burden, the major risk factors for chronic diseases are spreading. The prevalence of overweight and obesity is increasing in developing countries, and even in low-income groups in richer countries.”(8) Problems of overnutrition are increasing even in countries where hunger is prevalent.

Factors Contributing to Overnutrition

The United States is now engulfed in an obesogenic environment. The National Center for Health Statistics at the Centers for Disease Control and Prevention (CDC) estimated that in 2015-2016, the prevalence of obesity in the United States was 39.8% in adults and 18.5% in youth.(9) Obesity and overweight result from a variety of causes included individual behavioral and genetic causes. While many factors including genetics, drugs, and other medical conditions may contribute to obesity, behavior is perhaps the most common contributor. Individual level healthy weight is associated with a healthy diet and regular physical activity. Restaurants are serving incredibly caloric meals, with some meals containing 2,000 calories. People are becoming more sedentary in both the home and office.

This obesogenic culture has spread to other nations, including many developing countries. China, for example, now has more than 5,000 Kentucky Fried Chicken (KFC) restaurants in 1,100 cities.(10) Similarly, McDonald’s expects to have 4,500 restaurants in China by 2022, up from 2,500 in 2017.(11) Furthermore, a growing number of Chinese households own television sets, personal vehicles, and other technologies that reduce physical activity and facilitate weight gain.

Economic inequality in these nations is a primary cause of both overnutrition and undernutrition. Studies conducted in India show that income inequality had the same effect on the risk of being overweight as it did on the risk of being underweight; specifically, for each standard deviation increase in income inequality, the odds of being underweight increased by 19% and the odds of being obese increased by 21%.(12) While some people have the resources to purchase amounts of food beyond their daily caloric requirements, others cannot meet their recommended caloric intake. However, increasing numbers of poor people are becoming overweight in more nations, as these individuals consume affordable, yet highly caloric meals, such as fast food and processed foods.

Overnutrition Interventions

The WHO began sounding the alarm to the overnutrition epidemic in the early 1990s. Since then, the WHO has initiated public awareness campaigns targeting policy-makers, private sector partners, medical professionals, and the general population. The WHO began collaborating with universities, including the University of Sydney (Australia) and the University of Auckland (New Zealand), to understand the economic impact and factors of overweight and obesity.(13) The WHO has also formulated a Global Strategy on Diet, Physical Activity and Health, which outlines steps to combat global overnutrition.(14) The overall goal of the Global Strategy is to “promote and protect health by guiding the development of an enabling environment for sustainable actions at individual, community, national and global levels that, when taken together, will lead to reduced disease and death rates related to unhealthy diet and physical inactivity."(15)


(1) Chopra M, Galbraith S, Darnton-Hill I. (2002) "A Global Response to a Global Problem: The Epidemic of Overnutrition." Bulletin of the World Health Organization. 80:952-958.

(2) World Health Organization. “Double Burden of Malnutrition.”

(3) Ibid.

(4) Ibid.

(5) Ibid.

(7) Parks, N. "What Is Overnutrition and Undernutrition?" Livestrong.

(8) WHO. (2004) World Health Assembly. “Global Strategy on Diet, Physical Activity and Health.”

(9) CDC. “Prevalence of Obesity Among Adults and Youth, 2015-2016.” NCHS Data Brief No. 288, October 2017.

(10) Jacobs, H. "KFC is by far the most popular fast food chain in China and it's nothing like the US brand - here's what it's like." (April 15, 2018) Business Insider.

(11) Pisani, J. "McDonald's plans to nearly double restaurants in China." (August 8, 2017) USA Today.

(12) Subramanian SV, Kawachi I, Smith GD. (2007) "Income Inequality and the Double Burden of Under- and Overnutrition in India." Journal of Epidemiology and Community Health. 61:802-9.

(13) WHO. "Controlling the Global Obesity Epidemic." (2003)

(14) WHO. "Global Strategy on Diet, Physical Activity and Health." (2004)

(15) Ibid.