What happens when soft drinks are restricted?
With the UK sugar levy on sugar-sweetened beverages (SSB) fast approaching, and reformulation of products underway, it is interesting to consider how restriction of SSB might affect the nation’s health. This was considered in a US randomised controlled trial, one of the few that has tackled this important policy issue.
The SIPsmartER study recruited overweight, lower income adults to take part in an intervention to compare a physical activity programme (n=143) with voluntary restriction of SSB (n=149). Participants were followed up after 6 months to track changes in diet, body weight and metabolic profile.
The results showed that restricting SSB lowered consumption of these products by over 500ml a day, creating an energy deficit of 227 kilocalories. There were improvements in the Healthy Eating Index, consumption of ‘empty calories’ and vegetable intake compared with baseline and the physical activity programme. The impact on body weight was statistically significant but modest (0.5kg weight loss and -0.21 change in body mass index in the lower SSB group; 0.1kg gain in the physical activity group). There were no between condition effects for metabolic markers, e.g. blood lipids, glucose, blood pressure.
The authors concluded that asking participants to keep SSB intake below 240ml daily led to beneficial dietary changes and a modest impact on body weight. However, it is clear that this intervention on its own would be insufficient to tackle obesity on a population level. Check out the studies here and here.