NHS attacks ‘uncritical’ reporting of Nestlé Waters funded weight loss study

Published in the American Journal of Clinical Nutrition ​in February, the study by Tate et al. at the University of Carolina was supported by a grant from leading US bottled water firm Nestlé Waters.

It aimed to find evidence to support the theory that replacing high calorie drinks (which the authors linked to health problems including obesity) with water or diet drinks promoted modest weight loss, with drink replacement measures compared to simple information provision on a healthy diet.

Tate et al. wrote in their abstract: “Replacement of caloric beverages with non-caloric beverages as a weight-loss strategy resulted in average weight losses of 2% to 2.5%. This strategy could have public health significance and is a simple, straightforward message.​”​

Behind the headlines​

But in its ‘Behind the Headlines’ section, specialists writing for the NHS Choices website said the study results was reported uncritically in UK national papers: the Metro, Daily Express and Daily Mail​.

They wrote: “The claim that people who switch to water or diet drinks are twice as likely to lose 5% of their body weight sounds dramatic, but overall there was no significant difference in average weight loss between the groups.”​

Between 2008 and 2010, 318 overweight and obese people were recruited for the six-month duration of the trial. The average age of 42, of whom 84% were women and 54% were black.

Only subjects who consumed 280 calories or more of calorific drinks (juice and juice drinks, sweetened coffee and tea, sports drinks and alcohol) daily were allowed to take part in the trial.

Participants were encouraged to drink the firm’s water – rather than sugar-sweetened drinks – replacing two or more servings a day of calorific beverages with water or diet beverages, with four single servings of these drinks provided daily.

The study found that, on average, subjects in three groups lost weight (no other changes were made to diet or lifestyle) but, according to the NHS, failed to prove that diet beverage or water replacement was better than simply offering overweight people advice on how to lose weight.

Weekly weight readings were provided by participants online, and water drinkers lost on average 2.03% of their body weight, the diet drink group lost 2.45% and those in the control (advice only) group 1.76%. However, the difference in weight loss between groups was not statistically significant.

A further analysis did find that people in either water or diet groups were twice as likely to achieve a 5% weight loss target compared with the control group, but the NHS noted that the number achieving this result was unreported.

No weight loss ‘shortcuts’​

One study limitation was that it only included those who consumed more than 280 calories per day, the NHS noted, with 40% of subjects screened left out of the trial because they did not pass this threshold; thus there was some doubt as to whether study results were relevant to those who consumed fewer calories in the form of beverages.

In sum, the NHS agreed that sugar-sweetened drinks, juices, alcohol and similar beverage were a hidden source of calories, with most dieticians advising limited intake to maintain healthy weight.

“However, it is also important to maintain a healthy diet overall and to do regular exercise. There is no short cut to sustainable weight loss,” ​the health service said.

A spokeswoman for NHS Choices told BeverageDaily.com that such online comments had been central to the site since its inception, and were aimed at correcting perceived misreporting and preventing the spread of public concern.

Set up by Sir Muir Gray in 2007, Behind the Headlines aims to provide “unbiased and evidence-based analysis of health stories that make the news”​ to assist the public and health professionals.