During the course of the community discussion on a potential soda tax, we have cited our interview with Dr. Harold Goldstein. Some of his figures have come into question and so we asked Dr. Goldstein to provide the Vanguard with citations that back up the claims. He has done so.
Dr. Goldstein told us that the research suggests that the proliferation of sugar beverages over the last 40 years has greatly contributed to obesity problems. From 1977 to 2001, people consumed about 278 calories more and about 43 percent of those calories came from beverages.
He argued that consuming just one soda a day increases the risk of obesity by 50 percent and of diabetes by 30 percent.
In 2005, researchers SJ Nielsen and BM Popkin published a study in the American Journal of Preventative Medicine. They looked at changes in beverage intake between 1977 and 2001 and found for all age groups, “sweetened beverage consumption increased and milk consumption decreased. Overall, energy intake from sweetened beverages increased 135% and was reduced by 38% from milk, with a 278 total calorie increase.”
They add, “These trends were associated with increased proportions of Americans consuming larger portions, more servings per day of sweetened beverage, and reductions in these same measures for milk.”
In other words, the researchers found that the consumption of sweetened beverages more than doubled in that 24-year period and was a primary reason why caloric intake increased by 278 calories. This is backed up by subsequent research.
A 2010 meta-analysis published in Public Health Nutrition by Gail Woodward-Lopez, et al found that “Obesity rates and sweetened beverage intake have increased in tandem in the USA.”
They write, “Studies consistently show that higher intake of sweetened beverages is associated with higher energy intake. Energy in liquid form is not well compensated for by reductions in the intake of other sources of energy. Well-designed observational studies consistently show a significant positive relationship between sweetened beverage intake and adiposity. More importantly, several well-conducted randomized controlled trials have shown statistically significant changes in adiposity as a result of corresponding changes in sweetened beverage intake.”
They conclude, “All lines of evidence consistently support the conclusion that the consumption of sweetened beverages has contributed to the obesity epidemic. It is estimated that sweetened beverages account for at least one-fifth of the weight gained between 1977 and 2007 in the US population. Actions that are successful in reducing sweetened beverage consumption are likely to have a measurable impact on obesity.”
Pan A and Hu FB in 2011 published an article that found huge differences in the effects of carbohydrates on satiety between liquid and solid food. Satiety is the feeling of being full after eating food. It is a huge factor, because one of the problems with liquid drinks is that they do not fill people up like solid food does and thus many people will eat more.
The researchers here note, “A number of studies have examined the role of dietary fiber, whole grains, and glycemic index or glycemic load on satiety and subsequent energy intake, but results remain inconclusive. Intake of liquid carbohydrates, particularly sugar-sweetened beverages, has increased considerably across the globe in recent decades in both adolescents and adults. In general, liquid carbohydrates produce less satiety compared with solid carbohydrates. Some energy from liquids may be compensated for at subsequent meals but because the compensation is incomplete, it leads to an increase in total long-term energy intake.”
They find, “The physical form (solid vs. liquid) of carbohydrates is an important component that may affect the satiety process and energy intake. Accumulating evidence suggests that liquid carbohydrates generally produce less satiety than solid forms.”
In 2009, Harold Goldstein himself is a co-author on an article, “Bubbling over: soda consumption and its link to obesity in California.”
They write, “The prevalence of overweight and obesity has increased dramatically in both adults and children in the last three decades in the n California, 62% of adolescents ages 12-17 and 41% of children ages 2-11 drink at least one soda or other sweetened beverage every day. In addition, 24% of adults drink at least one soda or other sweetened beverage on an average day.”
For adults who drink soda occasionally (not every day), they “are 15% more likely to be overweight or obese,” but adults who drink one or more sodas per day “are 27% more likely to be overweight or obese than adults who do not drink soda, even when adjusting for poverty status and race/ethnicity.”
The research produced collaboratively by the California Center for Public Health Advocacy and the UCLA Center for Health Policy Research, examines soda consumption in California by cities and counties using data from the 2005 California Health Interview Survey (CHIS 2005). It also investigates whether there is an association between soda consumption and the prevalence of overweight and obesity.
They write, “There are major differences in soda consumption rates by geographic area in California, suggesting that social and environmental factors affect the consumption of soda. Also, the prevalence of overweight and obesity is higher among those who drink one or more sodas or other sweetened beverages every day than among those who do not consume these soft drinks. Establishing public policies that focus on reducing soda consumption could contribute to reversing California’s increasing overweight and obesity problem.”
The impact of sugar-sweetened beverages are even greater on children than adults. One meta-analysis looks at the odds of being overweight in children consuming one daily serving of sugar sweetened beverages, and found that children who drink at least one serving a day have 55 percent increased odds of being overweight or obese than children who rarely drink sugar-sweetened beverages. Mover, a 2009 study found that the “increase in consumption of sugar-sweetened soft drinks from childhood to adulthood was directly associated with BMI in adulthood in women,” but not in men.
They conclude “that direct associations exist between adulthood overweight and BMI and an increase in consumption of sugar-sweetened soft drinks in women. Thus sugar-sweetened soft drinks consumption may be important when considering weight management in women.”
Finally, other research indicates that “Latinos and African-Americans are more likely to consume sugar-sweetened beverages on a daily basis compared to whites.” The authors write, “This disparity is influenced by a lack of grocery stores, a high prevalence of convenience stores, and the low cost of sugar-sweetened beverages compared to healthier beverages in many predominantly Latino and African American communities, along with a long history of soda marketing that targets these communities.”
Recall that the beverage industry targeted their campaign against the San Francisco soda tax in the low-income neighborhoods, and found success.
—David M. Greenwald reporting