Nutrition

Picture warnings on fizzy drinks? A promising tool to fight childhood obesity

A study published in the journal PLOS Medicine is the first to examine whether pictorial health warnings on sugary drinks, like juice and fizzy drinks, influence whether or not parents purchase these types of beverages for their children.

The study’s results found that these warnings reduced parental purchases of sugary drinks for their children by 17%.

Researchers at the University of North Carolina at Chapel Hill’s Gillings School of Global Public Health ran the study in a unique laboratory by creating the “UNC Mini Mart”. This space was set up to mimic a convenience store and simulate a realistic setting for a shopping experience.

“We created this store because we saw a major need for research that tests the impact of policies in a food store setting that is much more realistic,” said senior author Lindsey Smith Taillie, PhD, assistant professor in the Department of Nutrition at the Gillings School and a member of UNC’s Carolina Population Center (CPC). “When people make choices about what food to buy, they are juggling dozens of factors like taste, cost, and advertising and are looking at many products at once. Showing that warnings can cut through the noise of everything else that’s happening in a food store is powerful evidence that they would help reduce sugary drink purchases in the real world.”

Taillie’s and her co-authors’ positive findings about the effects of image-based warning labels highlight a recent approach to combating the global struggle with obesity. Children in the United States and many other countries, including the UK, consume more than the recommended amount of sugary drinks, which increases their risk for obesity and other diet-related chronic diseases, including Type 2 diabetes. 

Taillie has conducted research on warning labels and taxes on sugar-sweetened beverages and junk food in Chile, Mexico and South Africa. Marissa G. Hall, PhD, one of the study’s co-authors, researches the impact of warnings on tobacco and food as well as effectiveness of obesity prevention policies.

In their study, 326 parents of children between the ages of 2 to 12 years old participated in a randomised trial with 1) a pictorial warning arm (in which drink labels had images representing heart damage and Type 2 diabetes), and 2) a control arm (in which drinks labels displayed a barcode).

Participants were instructed to choose one drink and one snack for their child, along with one household good, the latter being added to the shopping list to potentially mask the purpose of the study. After shopping, participants completed a survey about their selections and left with their drink of choice and a cash incentive.

The picture warnings led to a 17% reduction in purchases of sugary drinks, with 45% of parents in the control arm buying a sugary drink for their child compared to 28% in the pictorial warning arm.

The warnings also reduced calories purchased from sugary drinks and led to parents feeling more in control of healthy eating decisions and thinking more about the harms of sugary drinks. 

“We think the paper could be useful for policymakers in the U.S. and globally,” Hall says. “This evidence supports strong, front-of-package warnings to reduce sugary drink consumption in children.”

Can rye help reduce weight and obesity?

New research published in Clinical Nutrition has indicated that consuming whole grain rye products can benefit your health greater than refined wheat products. The new study was conducted at Chalmers University of Technology, Sweden. It examined how people lost more body fat and weight when eating a diet with high-fibre products containing whole grain rye, compared to those who ate refined wheat products.

This study is the biggest to look at the consequences of consuming specific grains on body weight and body fat, and the first to examine rye specifically. Scientists have also suggested that obesity is caused by what we are eating, and not by how much.

Researchers analysed 242 men and women with overweight aged from 30 to 70 for 12 weeks. Their weight, body composition, blood samples, and appetite was examined at the start, halfway through, and end of the study. The participants were given a specific daily quantity of either whole grain rye or refined wheat, both with the same energy value, and were given the same guidance from a dietician on how to eat healthily.

Although both the rye and wheat groups lost weight during the study, those who ate rye products lost an average of one kilogram more than those who ate wheat products, with the difference attributable to fat loss.

“Although we saw an overall difference in weight loss between the rye and the wheat group, there was also very large variation within those groups. Increasing our understanding of why different people respond differently to the same foods can pave the way for more specifically tailored diets based on individual needs,” says Rikard Landberg, Professor of Food and Health at Chalmers University of Technology.

Obesity and excess weight are among the biggest health challenges in the world and require many different measures. One idea is to develop foods that contribute to an increased feeling of fullness and have positive effects on metabolism, and previous studies had observed that those who eat rye, which has a very high content of dietary fibre, feel more full than those who eat the corresponding amount of energy in the form of refined wheat.

“But surprisingly,” says Kia Nøhr Iversen, “in this study, we actually never observed any difference in appetite. We think this may be simply because the method we used to measure appetite was not good enough. We are therefore working on evaluating and developing the method further.”