Obesity Overview

The World Health Organization (WHO) defines obesity as excessive fat accumulation compared to a healthy weight. Body mass index (BMI) is widely used to determine whether a person is overweight or obese. If an adult’s BMI score is 30 or higher, then he or she is classified as obese according to WHO’s definition. According to WHO statistics, the number of people who are obese has more than tripled since 1975. As of 2016, over 650 million people worldwide are facing obesity issues. 

Prevalence of Self-Reported U.S Adult Obesity Rate. (Source: Behavioral Risk Factor Surveillance System)

Obesity is a severe problem for the whole world, and especially for the United States. The latest Centers for Disease Control and Prevention (CDC) statistic shows that more than 30% of the U.S adults and 20% of the U.S children population are obese. A research study conducted by Simmonds et. al. suggested that if a kid is suffering from childhood obesity, he or she has a five times higher risk of becoming obese as an adult compared with those without childhood obesity. Their study also found that the obesity risk increases as the person gets older. Obesity has major implications for America’s health and economy.

1. Obesity-related chronic diseases. National Institute of Diabetes and Digestive and Kidney Diseases (NHI) research shows that obese people are vulnerable to certain health issues including type II diabetes, cardiovascular diseases, etc.  
2. Obesity-related economic impact. The U.S government spends $190 billion on obesity-related healthcare since 2015, and the amount of money increases year by year. The expense of obesity-related absenteeism ranges between $3.38 billion and $6.38 billion annually in the U.S. 

The Causes of Obesity

Various factors can cause excess weight gain and fat accumulation in the human body, which makes obesity a complex health issue.

• An unbalanced diet and overeating: Less than 10% of U.S children and adults meet the CDC recommended amount of daily vegetable intake. Instead, study shows that high-calorie, sugar-dense, and fat-dense foods are cheap and easy to access. These types of foods can be found in vending machines, supermarkets, restaurants, etc., and they take up a large proportion of the food market. On the other hand, families prefer to buy frozen foods and pre-packaged foods because they are affordable and easy to prepare. However, these types of foods are calorie-dense. When a person feels full from eating these types of foods, he or she eats far more calories than the healthy calorie intake level. 
• Inadequate physical activity: The CDC recommended physical activity level for health benefits for an adult is 30-minutes of moderate-intensity aerobic activity five days a week (150 minutes in total) and at least two days per week for muscle-involved activities. However, according to the CDC physical activity level report from 2001 to 2005, less than 50% of U.S adults met the basic recommended physical activity level. The percentage of U.S adults who meet the basic physical activity level of CDC recommendation dramatically decreases year by year. The latest CDC physical activity level report shows that only one-quarter of U.S adults meet physical activity guidelines.
• Social determinants of health (SDOH): Over 50% of U.S households are unable to access the park within their community or need to travel more than half a mile to the park. In addition, 40% of U.S households do not have access to full-service grocery stores within their community. People who live in such SDOHs may have a hard time making healthy food choices, which increases their risk of becoming obese. 

Sugar-Sweetened Beverage (SSB) and Consumption

Sugar-sweetened beverages (SSB) are the main sources of added sugar in U.S household diets, which are large contributors to the obesity rate. The CDC defines SSB as “any liquids that are sweetened with various forms of added sugars like brown sugar, corn sweetener, corn syrup, dextrose, fructose, glucose, high-fructose corn syrup, honey, lactose, malt syrup, maltose, molasses, raw sugar, and sucrose.” According to the National Health Interview Survey Cancer Control Supplement (NHIS CCS), from 2010 to 2015, about six in ten U.S adults drank SSB one or more times per day. Although the prevalence of SSB intake differs in states, the consumption of SSB ranges from 44.5% to 76.4%.

Sugar-Sweetened Drink Taxes Policy

A Sugar-Sweetened Drink Tax (SSDT) represents one policy strategy to reduce sugar consumption in communities. The tax targets suppliers that produce beverages (such as sports drinks, fruit drinks, tea, etc.) with added sugar (“a total sugar content of five grams or more per 100 milliliters”) and sell their products across state lines. Because SSDTs have only been introduced recently, this policy has not been widely implemented in the U.S. Several cities have levied SSDTs locally including Boulder, Navajo Nation, Cook County, Philadelphia, Seattle, Berkeley, Albany, Oakland, and San Francisco. In addition, SSDTs have been adopted by over forty other countries. 

Cities Implemented SSDT Across the U.S. (Source: Healthy Food America)

SSDTs effectively reduce sugar consumption by increasing the price and reducing the sale of SSBs. The rate of SSDT varies among cities. For example, the SSDT for cities in California is 1 cents per ounce, and it is 2 cents per ounce in Boulder. Such taxes on SSB products result in a 43% to 120%  price increase for consumers. The volume of SSB sales in cities that adopted SSDT decreased by 21 to 39 percent. 

Challenges 

Some critics have argued that SSDT was implemented prematurely, and inadequate data and poor policy design make it difficult to determine if the policies are actually effective. Further, some unintended consequences have been observed after implementing SSDT.

1. SSDTs tend to be regressive taxes because low-income families spend a larger proportion of their income on groceries compared to high-income families. As a result, SSDTs have a disproportionate impact on lower-income households. 
2. SSDT does not directly reduce the amount of sugar in drinks, and it does not necessarily reduce sugar consumption. Based on SSDT content, all per-unit SSDT is calculated using the volume of qualifying beverage rather than the sugar content. In other words, the tax for an eight-ounce iced tea (which contains two teaspoons of sugar) is equal to the tax rate for an eight-ounce soda (which contains seven teaspoons of sugar). 

Benefits of SSDT

Currently, cities that implemented SSDT are spending SSDT revenue ($135 million per year) to address their specific healthcare needs and improve low-income community health. These cities focus on increasing public awareness of healthy beverages and diabetes through social media and education campaigns. Specifically, Albany, CA, spends SSDT revenue for local healthcare and youth nutrition education. Boulder, CO, reaches out to local restaurants, markets, and drink producers to reduce misinformation regarding SSB. Seattle, WA, boosts access to nutritious food and water and educates people about nutrition and healthy beverage options. SDOH, including parks, leisure facilities, and sports fields, are addressed. In addition, SSDT revenue is also used to enhance the obesity-related healthcare system.