Dietary sugars and body weight

This week's issue of the British Medical Journal investigates the effect of dietary sugars and body weight.

Dr Mann and colleagues summarized evidence on the association between intake of dietary sugars and body weight in adults and children.

The team performed a systematic review and meta-analysis of randomized controlled trials, and prospective cohort studies.

The team searched OVID Medline, Embase, PubMed, Cumulative Index to Nursing and Allied Health Literature, Scopus, and Web of Science.

The researchers identified eligible studies that reported the intake of total sugars, intake of a component of total sugars, or intake of sugar containing foods or beverages, and at least one measure of body fatness.

The doctors reported that the minimum duration was two weeks for trials, and one year for cohort studies.

Trials of weight loss or confounded by additional medical or lifestyle interventions were excluded.

Study selection, assessment, validity, data extraction, and analysis were undertaken as specified by the Cochrane Collaboration and the GRADE working group.

For trials, the team pooled data for weight change using inverse variance models with random effects.

The team found that 30 of 7895 trials, and 38 of 9445 cohort studies were eligible.

Isoenergetic exchange of dietary sugars with other carbohydrates showed no change in body weight

British Medical Journal

The researchers noted that in trials of adults with ad libitum diets, reduced intake of dietary sugars was associated with a decrease in body weight.

The team observed that increased sugars intake was associated with a comparable weight increase.

Isoenergetic exchange of dietary sugars with other carbohydrates showed no change in body weight.

The research team found trials in children involved recommendations to reduce intake of sugar sweetened foods and beverages.

The team noted that these trials had low participant compliance to dietary advice, and showed no overall change in body weight.

However, in relation to intakes of sugar sweetened beverages after one year follow-up in prospective studies, the odds ratio for being overweight or obese increased was 1.6 among groups with the highest intake compared with those with the lowest intake.

The docotrs reported that despite significant heterogeneity in one meta-analysis and potential bias in some trials, sensitivity analyses showed that the trends were consistent and associations remained after these studies were excluded.

Dr Mann's team concludes "Among free living people involving ad libitum diets, intake of free sugars or sugar sweetened beverages is a determinant of body weight."

"The change in body fatness that occurs with modifying intakes seems to be mediated via changes in energy intakes, since isoenergetic exchange of sugars with other carbohydrates was not associated with weight change."