Soft Drinks and Weight Gain: How Strong Is the Link?

Soft Drink Consumption and Marketing Trends

The United States has experienced dramatic increases in soft drink consumption over the past few decades, largely due to economic and societal forces encouraging this behavior. In 2004, Americans spent $66 billion on carbonated drinks, and the soft drink industry produced approximately 52 gallons per year of sugar-sweetened and "diet" soda -- or 18 oz per day -- for every man, woman, and child in the United States.^[11] In 1942, the US annual production of carbonated drinks was approximately 2 oz per person per day,^[11] such that in the last 6 decades, per capita soda production has increased nearly 10-fold. The proportion of persons of every age consuming soft drinks has increased over the past 20 years, as have portion sizes of soft drinks and the number of servings consumed.^[12] Between 1977 and 2001, Americans increased total energy from soft drinks from 2.8% of energy to 7.0% of energy, which translates into almost tripling of calories per day (from 50 kcal to 144 kcal).^[12] During this time period, soft drink intake also increased from 4.1% to 9.8% of energy for 19- to 39-year olds, the group that consumed the highest levels of caloric beverages and soft drinks.^[12]

Soft drinks are aggressively marketed, and 2 companies -- Coca-Cola and PepsiCo -- dominate sales in the United States. In 1999, Coca-Cola held a 44% market share worth $7.5 billion in sales, whereas PepsiCo held a roughly 30% share of the US market.^[11] In 2004, Coca-Cola spent $2.2 billion on global promotions and sold $22 billion worth of beverages in the same year.^[11] Coca-Cola sells its soft drinks in the United States at 2 million stores, at more than 450,000 restaurants, and from 1.4 million vending machines and coolers. Industry-wide, in 2000, 3 million soft drink vending machines dispensed about one seventh of all soft drinks sold.^[11]

High-fructose corn syrup is the principal sweetener for regular soft drinks. In 1970, high-fructose corn syrup represented < 1% of all caloric sweeteners available for consumption in the United States, but in the 1980s, the high-fructose corn syrup market jumped rapidly as the soft drink industry began to use this inexpensive, sweet corn-based syrup instead of sucrose. Due to the low cost of the sweetener, which consists of 55% fructose, 42% glucose, and 3% other sweeteners, it made it profitable to replace sucrose with high-fructose corn syrup, and by 2000 it represented 42.0% of all added caloric sweeteners in the American diet.^[13,14] Today, sugar-sweetened beverages consist of 7% to 14% added sweeteners, which are most often high-fructose corn syrup, and soft drinks are the largest source of added sweeteners, accounting for one third of the added sugar intake in the American diet.^[14] Total consumption of fructose has increased by 30% in the United States over the past 30 years.^[13] From 1970 to 1997, annual per capita intake of high-fructose corn syrup increased from 0.5 lb to 62.4 lb.^[3] The increase in high-fructose corn syrup consumption over the past several decades exceeds the increase in intake of any other food or food group during that time. High-fructose corn syrup is now used not only in sweetening carbonated beverages, but also baked goods, candies, salad dressings, and other processed foods.^[3]

Medscape J Med. 2008;10(8):189 © 2008  Medscape

Cite this: Soft Drinks and Weight Gain: How Strong Is the Link? - Medscape - Aug 12, 2008.