WASHINGTON — A new study published in The Journal of the American Medical Association (JAMA) showing rising obesity rates over the last decade and recent data from the Economic Research Service (E.R.S.) of the U.S. Department of Agriculture showing declining sweetener consumption during the same period has provided fodder for the Sugar Association to question whether sugar should be the primary target in the fight against obesity.

“Sugar has been targeted as Public Enemy No. 1 in the fight against obesity,” the Sugar Association said. “But is it really where we should be placing all the blame? Per capita consumption of added sugars has declined 15% since 1999. Not only have rates of obesity not gone down, they continue to rise as we eat less added sugars. The numbers just don’t add up.”

The JAMA Network reported on a study by the Centers for Disease Control and Prevention that analyzed data from 2,638 men and 2,817 women in 2013-14 and compared findings with data from 21,013 participants in surveys from 2005 through 2012. It showed an obesity rate of 35% among men and 40% among women compared with 34% for men and 38% for women a decade ago. Class 3 obesity (morbid obesity with body mass index over 40) was 5.5% for men and 10% for women in the latest study.

“For women, the prevalence of overall obesity and class 3 obesity showed significant linear trends for increase between 2005 and 2014; there were not significant trends for men,” the study concluded in part.

“The authors write that although there has been considerable speculation about the causes of the increases in obesity prevalence, data are lacking to show the causes of these trends, and there are few data to indicate reasons that these trends might accelerate, stop or slow,” The JAMA Network said in its review of the study.

Meanwhile, E.R.S. data show a 1% decline in total caloric sweetener deliveries and a 9% decline in per capita deliveries from 2005 to 2015, although total deliveries increased slightly in 2015 from 2014 while per capita deliveries declined slightly.

Caloric sweeteners included in the E.R.S. total were high-fructose corn syrup, glucose syrup, dextrose (all corn sweeteners), refined sugar, pure honey and other edible syrups. The E.R.S. noted that it was important to distinguish between sweetener deliveries, which represent the amount of product marketed and shipped from processors or refiners to users and consumers, and sweetener consumption (ingested by consumers), which is less than deliveries due to losses from shrinkage, spoilage and waste.

Total caloric sweetener deliveries peaked at 21,709,000 short tons, dry basis, in 1999 and fell to a low of 20,009,000 tons in 2009. Total deliveries increased the past two years to 20,709,000 tons in 2015, but were down 1% from 2005 and down 2% from the 1999 peak.

A breakdown of sweeteners within the 1999 total shows 44% was refined sugar, 55% was corn sweeteners and 1% was honey and other syrups. In 2005 the mix was nearly the same as in 1999, but in 2015 the mix had changed to 53.6% refined sugar, 44.8% corn sweeteners and 1.6% honey and other syrups.

The change in the mix of total caloric sweeteners represents the trend away from corn sweeteners (especially HFCS) and back to sugar and other “natural” sweeteners such as honey. Total corn sweetener deliveries peaked at 11,694,000 tons in 2002 and were 28% greater than refined sugar deliveries that year. HFCS deliveries rose from zero in 1966 to a peak of 8,998,000 tons in 2002 (just 1% less than sugar) and since have declined 24% to 6,824,000 tons in 2015, the lowest level since 1992.

“The most substantial change between deliveries in 2005 and 2015 came from the beverage sector, which increased from 2.6% of total sugar deliveries in 2005 to 7.7% in 2015, likely due to the substitution of sugar for HFCS,” the E.R.S. said. Sugar deliveries to the beverage sector totaled 616,489 tons, actual weight, in 2015, nearly 2.6 times the amount delivered in 2005, according to the U.S.D.A.’s Sugar Market Data report.

The largest industry user of sugar remains bakery, cereal and related products at 2,429,979 tons in 2015, up about 8% from 2005 and equal to 24% of total deliveries (unchanged from the 2005 share).  

Another factor in sugar and HFCS consumption was the Jan. 1, 2008, implementation of the North American Free Trade Agreement, which allowed unlimited, duty-free U.S. imports of sugar from Mexico and U.S. exports of HFCS to Mexico, until a Dec. 19, 2014, bilateral agreement limited exports of Mexican sugar to the United States (but not U.S. exports of HFCS to Mexico) after U.S. sugar producers charged Mexico with dumping subsidized sugar on the U.S. market. U.S. refined sugar deliveries jumped 7% in 2008, dipped slightly in 2009 and have been rising ever since, topping out at 11,098,000 tons in 2015, the highest in at least the last 50 years. HFCS deliveries fell 5% in 2008, the first year of NAFTA, and have been declining ever since with the exception of a small increase in 2014.

The U.S. population has increased about 9% since 2005 to an estimated 321.4 million in 2015. Total per capita sweetener deliveries peaked at 151.6 lbs, dry basis, in 1999, and have declined 15% to 128.9 lbs in 2015 (down 9% from 142.2 lbs in 2005), which was the second lowest (after 128.1 lbs in 2013) since 128.5 lbs in 1989.

The Sugar Association also cited an earlier report from the E.R.S. that showed American diets have increased by more than 500 calories per day since 1970, but added sugars made up only 34, or 7%, of the added calories, while calories from fats and grains increased by five times as much as those from added sugars. Meanwhile, screen time (television, video games, etc.) at more than three hours per day for high schoolers has doubled since 2003, the Sugar Association said.  

Data from the C.D.C. in February showed obesity among adults 20 and over was at an all-time high in 2015 at 30.6%, up slightly from 2014.

“Americans are eating more — of everything — and moving less,” the Sugar Association said. “The cause and solution to obesity is complicated and the role that diet plays certainly isn’t as simple as focusing on one ingredient — despite how easy that seems. Reducing total caloric intake from ALL sources and getting people moving needs to be priority No. 1.”