Guess what happens when you ask people to cut soda

San Francisco, Oakland, Chicago and Philadelphia, my fair city, recently passed soda taxes. But the first to enact such a policy was obesity-ridden Mexico. The sugary drink tax was enacted there in 2014, and it seems to work. In its first year sales of sugary drinks fell by as much as 12 percent, and a recent study showed that it wasn’t just a blip -- they continued to fall in the second year, with a decline of about 10 percent.

Public health advocates hope that a reduction in sugary drink consumption will lead to a reduction in chronic diseases such as diabetes and heart disease, and to slimmer waistlines -- which makes a lot of sense, but still needs to be proven. Time will tell if that is indeed the case.

But here’s some encouraging evidence.

A new study published online ahead of print in the American Journal of Clinical Nutrition has some heartening findings that suggest that the soda habit is a keystone one, and when you work on changing it, other healthy behaviors follow naturally.

The soda cluster

When people sign up for a weight loss program they follow a whole set of guidelines, targeting many aspects of their diet and physical activity. But what would happen if people were advised to just cut sugary drinks?

Researchers, led by Valisa Hedrick, looked at 149 participants in a program called SIPsmartER – a study that targets only sugary drinks. Most of the volunteers (~80 percent) were overweight or obese, and they were followed for 6 months.

Cutting soda, the study showed, led to other positive dietary changes.

Guided to just cut sugary drinks the volunteers cut soda and sweetened coffee, and without further instruction also decreased trans-fats, artificial sweeteners, salt and total calories. They ate more veggies. The sugary drinks that were omitted were not replaced by a compensatory sweet dessert; they were replaced by water and non-caloric drinks.

The participants, in fact, ate 285 fewer daily calories, and the sugary drinks they skipped accounted for just half of this reduction.

One of the arguments the sugary drink and snack industry puts forward whenever health advocates suggest that their products should be consumed with moderation is that the energy imbalance can be addressed by expending more energy -- moving more. If we just exercise enough, they suggest, we could continue the soda and chips binge.

Here’s the thing: In this study the researchers compared the SIPsmartER participants to 143 volunteers in another single intervention study that focuses only on physical activity, called MoveMore. Moving more the study showed, didn’t lead to eating better. There was minimal reduction in soda drinking in this group, too, suggesting that exercise is a potential gateway to better health.

But the less-soda gateway is much more promising.

Changing habits is hard, and although a comprehensive healthy lifestyle intervention for all would be ideal, it’s not really feasible. Health experts agree that if you drink soda and sugary drinks, that’s the first habit to target – because these drinks are just empty calories that account for much of the excess added sugar in our diet and don’t lead to satiety.

This approach is also promising because soda drinking clusters with other unhealthy eating habits. Delete the soda, and good things start to happen.

Drink better, and better eating becomes easier.

Dr. Ayala

“The sugary drink habit is a keystone one, and when you work on changing it, other healthy behaviors follow naturally”