Sugar-sweetened beverage sales ban contributes to lower intake

While by no means the only culprit in the ongoing obesity crisis, sugar-sweetened beverages certainly play a significant role in overweight, obesity, and related health problems. Research has shown that drinking sugar-sweetened soft drinks contributes to weight gain and that those who consume the most calories from these beverages have poorer metabolic scores, including insulin resistance. Indeed, women who drink more sugar-sweetened soft drinks have a greater risk of stroke, and the list of studies linking poorer health and health outcomes with sugar-sweetened beverages just keeps getting longer.

At the most simplistic level of simple body weight, it does make sense: if a 12-ounce can of soda is about 150 calories (depending on the brand), drinking a 6-pack a day adds 900 calories to your daily caloric intake. That's easily about half of the total number of calories most people need in one day. The evidence also shows, however, that when people consume their calories in liquid form, their bodies don't seem to perceive the calories in the same way as they would calories from a food that required chewing: the body does not see liquid calories to be as satisfying as more solid calories.

So if you're used to drinking a lot of sugar-sweetened beverages, what happens when your access to them is reduced?

In 2015 the University of San Francisco banned the sales of all sugar-sweetened beverages across the university's campuses, including the medical center. The authors of this study, published in JAMA Internal Medicine (2019;doi:10.1001/jamainternmed.2019.4434), seized the opportunity to find out if this workplace ban would have any health-related effects on the university's employees.

Two months before the ban, the authors recruited 214 university employees who habitually drank at least 12 ounces of sugared beverages per day, were able to participate in fasting blood tests, and were neither pregnant, nursing, nor working the night shift.

About half of the participants were assigned to receive "a brief motivational intervention", in which a health educator described the amount of sugar the participant likely ingested given their daily intake of sugar-sweetened beverages, the possible effects, and gave guidance on reducing sugar intake and setting health goals related to the participants' intake of sugar-sweetened beverages. The other half of the participants received no such motivational intervention.

The 214 participants were between 18 and 68 years of age, and 2 months before the ban had an average Body Mass Index of 29.1 (clinically obese). All of the participants had blood drawn for tests and other physical measurements (weight, height, waist and hip measurements, etc.) two months before and 10 months after the ban on sales of sugar-sweetened beverages at campus-related locations.

The changes in sugar-sweetened beverage intake before and after the ban are quite striking: Two months before the ban, the participants consumed, on average, 1050 milliliters (about 35.5 ounces, or just about 3 12-ounce cans) of soda per day, while 6 months after the ban the average intake was cut to 540 milliliters, or a little more than 18 ounces (1.5 cans of soda). After 12 months the average dropped further to 522 milliliters (about 17 and one-third ounces).

The biggest difference was between those who received the health intervention and those who did not: those who received the health intervention, which included one in-person meeting and two brief phone calls over the course of the study, cut their sugar-sweetened beverage intake much more than those who didn't, reducing their intake by 762 milliliters (about 26 ounces, or about 2 and one-fourth cans of soda), while those who did not receive the intervention only cut their intake by about 264 milliliters (about 9 ounces, or 3/4 of a can).

Did this make much of a difference, health-wise? Yes and no. Although the average Body Mass Index didn't change, the participants' waist circumference dropped by about an inch, on average, although this didn't impact their waist-to-hip ratio (as their hips also grew smaller). Overall, those who were clinically overweight or obese improved their HDL cholesterol (the good cholesterol), while those who were of clinically normal weight at the start of the study not only improved their HDL cholesterol but also their total and LDL cholesterol.

What this means for you

This study is small and of comparatively short duration, but it does suggest that making sugar-sweetened beverages less ubiquitous might have a measurable effect on people's intake - and by extension, some impact on their health.

Remember, although the University stopped selling sugar-sweetened beverages, that did not mean that students and staff could not bring their own onto campus - nor did it stop people from consuming those drinks while on (or off) campus: they simply couldn't buy them on campus.

Another problem is that the participants knew that they would be reporting on their consumption of sugar-sweetened beverages, and although the researchers assured the participants that the information wouldn't be shared with the university itself (or its provider of health insurance), the participants might have felt motivated to underreport their consumption for that reason or simply to make themselves look more healthy to the investigators.

First posted: October 30, 2019