• Research and White Papers
  • September 2020
  • 10 minutes

Obesity: A Silent Pandemic

How dietary trends are changing the future of non-communicable diseases

Individual taking a bite out of a burger
In Brief

Millions of overweight and obese individuals are at increased risk of non-communicable diseases and early mortality than the non-obese. RGA's Hilary Henly explores what insurers need to know about the consequences of rising obesity rates and dietary trends across the globe.

For life and health insurers, increased incidence of obesity-related diseases will affect future risk assessment in underwriting as well as claims from non-communicable diseases (NCDs) such as diabetes and heart disease. This article identifies countries with rising rates obesity and considers the potential consequences for future generations. Trends toward diets such as the ketogenic diet and specific risks associated with these diets are also discussed. A separate COVID-19 Brief examines the risks of obesity related to that disease.

Global Crisis

By 2016, a stark 1.9 billion adults were overweight, of whom 650 million were obese. According to the World Health Organisation (WHO), around 39% of all adults aged 18 and over were overweight, and 13% were considered obese in 2016. The obesity epidemic was first seen in the U.S. but has rapidly spread to all parts of the globe, with worldwide prevalence of obesity nearly tripling between 1975 and 2016. In China, approximately 7.1% of adults were obese in 2002 but by 2020, this figure had risen to 12.0%, accounting for 20% of all obese individuals worldwide. China recorded the highest number of obese people in the world, directly followed by the U.S.1

In particular, the rising rate of obesity in children globally is a very worrying trend. The rate of increase in childhood obesity has been greater than the rate of increase in adult obesity in many countries. Much of the reason for the significant increase has been linked to the consumption of foods rich in saturated fats, salt, and sugar. Obesity can lead to the onset of diabetes, hypertension, heart disease, cancer, and osteoporosis.2

What is Obesity?

Obesity is an excess accumulation of body fat (20% above normal body weight), which has a detrimental effect on health. Usually, overweight is defined as a BMI exceeding 25 kg/m2, and obesity is defined as a BMI of 30 kg/m2 or more.2,3 However, ethnicity-based cut-offs for BMI can vary.

Table 1: 
Body Mass Index (BMI)4



BMI (kg/m2)



Normal weight

18.5 to < 25


25 to <30

Obese I

30 to <35

Obese II

35 to <40

BMI is a common indicator used to measure overall obesity, while abdominal obesity is measured using waist circumference, waist-to-height ratio (WHtR), or waist-to-hip ratio (WHR). These provide information on fat distribution and have been shown to be a strong predictor of the increased risk of non-communicable diseases (NCDs), independent of BMI. WHtR is calculated by dividing waist circumference by height, while WHR is calculated by measuring the circumference of the waist divided by the circumference of the hip. The WHO states that abdominal obesity is defined as a WHR above 0.90 for males and above 0.85 for females.5

See also: Wellness in Insurance: A Coming of Age Story


The most obese country in the world is Nauru, located in the southwestern Pacific Ocean, where the average person’s body mass index (BMI) is 32.5 kg/m2. Of the top ten most obese countries in the world, seven are in Oceania. Outside of Oceania, the most obese country is Kuwait, where the average BMI is 30 kg/m2. Rising rates of obesity have been attributed to eating a more Westernized diet, including the consumption of processed fast foods rather than more traditional cuisines.6 Ethnicity plays a significant role in obesity trends, with Asian children four times more likely to be obese than children of white ethnicity. Studies report that Asian people have higher body fat content and are more likely to develop abdominal obesity than Western people with the same BMI.7

In 2019, the WHO estimated that half of children who are overweight or obese live in Asia. The number of overweight and obese children and adolescents below age 20 was as high as 23% in China and 22.5% in Malaysia.7 Elsewhere, obesity prevalence was at or above 20% in parts of Polynesia, Micronesia, the Middle East and North Africa, the Caribbean, and the U.S.8

Figure 1: 
Obesity rates and average BMI by country 20206

If the current trend in weight gain continues, females will lose about 2.4 months in life expectancy and males around 4 months by the middle of this century.

Figure 2: 
Projected rates of obesity (Organisation for Economic Co-operation and Development - OECD)9

Dietary Trends

The rise in diet-related obesity in Southeast Asia is alarming; overweight and obesity rates in the region increased by nearly 40% from 1990 to 2013. Urban trends and lifestyle changes have led more people in Asia to consume western-style convenience foods, which are now widely available and often cheaper than traditional foods. Dietary patterns have moved away from traditional foods such as rice, vegetables, and fruits toward a more Westernized diet featuring more animal-sourced and energy-dense foods high in saturated fats and salt. This includes processed fast foods and ready-meals, sugar-loaded snacks and drinks, and a high intake of caffeine. As these countries in Southeast Asia become more urbanized, a larger number of people are likely to consume a poorer diet, and rising rates of non-communicable diseases (NCDs) are predicted to continue.7

See also: Increasing Urbanization Brings New Challenges for Life Insurers

Obesity-Related Conditions

Dietary changes are leaving people exposed to an increased risk of non-communicable diseases such as hypertension, heart disease, diabetes, and cancer. In the next 30 years, estimates predict that obesity will cause 220 million cases of NCDs in OECD countries.10 Globally, cardiovascular disease was the leading cause of death related to high BMI in 2016, accounting for 41% (2.7 million) of all BMI-related deaths. Analysis from the Global Burden of Disease Study 2010 showed that suboptimal diet and high blood pressure were the primary risks for cardiometabolic deaths.11

Fast Facts3,7

  • Diabetes is 80 times more prevalent in obese adults than the non-obese

  • The risk of coronary heart disease (CHD) is 2-3 times higher in obese adults

  • Overweight or obese adults are at increased risk of at least 13 types of cancer

  • Obese adults are 40% more likely to die from cancer than non-obese adults

  • Obese adults are 3-4 times more likely to suffer from depression than non-obese adults

  • Obese women are 37% more likely to die by suicide than non-obese women

Diabetes was the second leading cause of BMI-related deaths, accounting for 0.6 million deaths.12 The number of people with diabetes worldwide is projected to rise to 552 million by 2030 with the greatest increases in China (from 90 million to 130 million) and India (from 61 million to 101 million).13

See also: The Expanding Diabetes Classification Matrix: Types 1, 2, And More…

Data from the Singapore Chinese Health Study (SCHS) showed that Chinese Singaporeans who ate Western-style fast foods more than twice a week had a 27% increased risk of developing Type 2 diabetes (non-insulin dependent diabetes mellitus - NIDDM) and a 56% increased risk of dying from CHD.13

Table 2: 
Adjusted hazard ratios (HRs) for NIDDM and CHD relative to frequency of intake of Western-style fast food14


No Intake

Intake 1-3 per month

Intake 1 per week

Intake > 2 per week

NIDDM incidence





CHD mortality





The increased consumption of red meat has been identified as being largely responsible for these rapidly rising rates. For insurers, rising incidence of NCDs will ultimately result in more early death claims and claims under critical illness, hospital cover, and disability income.

Ketogenic (Keto) and Other Low-Carbohydrate Diets

The keto diet was first introduced in 1921 as a treatment for epilepsy. While consuming a ketogenic (keto) diet often leads to weight loss, studies show that it can also result in insulin resistance and increased glucose output. Normally, a Westernized diet compromises around 55% carbohydrate intake per day, whereas the keto diet is divided into amounts of 55-60% fat, 30-35% protein, and only 5-10% carbohydrates.15

Low-carbohydrate diets with higher intakes of protein or fat have gained significant popularity in recent years due to their ability to induce short-term weight loss. When carbohydrates are reduced to less than 50g per day, insulin secretion falls. Glycogen reserves are then depleted as a result, and metabolic changes such as ketogenesis occur. The formation of ketone bodies occurs primarily in the liver through the breakdown of fatty acids in body fat. Ketogenesis provides an alternative source of energy in place of glucose for use by most tissues in the body. Due to the low blood glucose, insulin secretion is low, which reduces the stimulus for fat and glucose storage. This can cause minor short-term side effects such as headache, fatigue, insomnia, and nausea, often referred to as ”keto flu.” Keto products include bars, oil, and protein powders with a selection of keto-based meals and menus available online.16

Some studies suggest that low-carbohydrate diets (LCDs) may increase the risk of cardiovascular disease.  Analysis of data on diets from the National Health and Nutrition Examination Survey (NHANES) 1999-2020 provides insights into the long-term association between LCDs and mortality. Participants with the lowest carbohydrate but higher fat intake (Table 3, first column) had the highest risk of overall mortality (32%), cancer mortality (35%), CHD mortality (51%) and cerebrovascular disease mortality (50%) compared to participants with a high-carbohydrate diet (Q1). Participants with a low carbohydrate but lower fat intake (Table 3, second column) still had a significant positive association of all-cause and cause-specific mortality.17

Table 3: 
Multivariable adjusted HRs for all-cause and cause-specific mortality Q4 versus Q1 (Ref: Carbohydrates: 367 Protein: 77, Fat: 73 g/day)17

Macronutrient amount (g/day)

Q4: Low carbohydrate, high fat diet

Q4: Low carbohydrate, low fat diet

All-cause mortality



Cancer mortality



Coronary heart disease mortality



Cerebrovascular disease mortality



Additional studies include:

  • The 2017 Prospective Urban Rural Epidemiology (PURE) study investigated the association of fats and carbohydrate intake with cardiovascular disease and mortality in 18 countries across five continents. Results showed that a higher carbohydrate intake was associated with an increased risk of all-cause mortality of 28% (HR 1.28) but not with a risk of cardiovascular disease mortality.17
  • The Kuopio Ischaemic Heart Disease Risk Factor Study (KIHD) of men from eastern Finland found that the group who consumed the highest amount of animal protein had a 43% increased risk of heart failure.18
  • The Atherosclerosis Risk in Communities (ARIC) study is an ongoing study of cardiovascular risk factors in four U.S. communities. The highest risk of early mortality was in individuals with the lowest carbohydrate consumption. Increased consumption of animal-based protein and fat in place of carbohydrate was associated with increased all-cause mortality (HR 1.20). Increased consumption of plant-based protein and fat in place of carbohydrate was associated with a significant decrease in all-cause mortality (HR 0.86).19

While more research will no doubt follow, it appears that a moderate consumption of carbohydrates and fats is most beneficial to overall health, and that a low-carbohydrate diet replaced by animal fats and proteins increases all-cause and cause-specific mortality.


Millions of overweight and obese individuals are at increased risk of non-communicable diseases and early mortality than the non-obese. Food choices and nutritional intake have changed significantly over recent decades, which has increased rates of excess weight and obesity in most countries around the world. Significant increases in obesity rates in Asia and the Pacific regions are predicted to continue, leading to rapidly rising rates of diabetes and heart disease. The consequences for insurers are that this will ultimately lead to a higher number of early death claims and a significant increase in health claims for NCDs. On the other hand, this could also represent an opportunity for insurers to develop and implement wellness or primary and secondary prevention programs for their clients. Adoption of low-carbohydrate diets, thought by many to be a potential solution to the obesity pandemic, are proving to bring their own mortality risks insurers should be aware of. 

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Meet the Authors & Experts

Hilary Henly
Hilary Henly
Global Medical Researcher, Strategic Research 


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