Juices made of 100% fruit can have a slight impact on children’s body mass index (BMI), which increases with each serving consumed. In addition, an effect on weight is noticeable in adults. These are some of the conclusions drawn from a literature review and meta-analysis published in JAMA Pediatrics.
“Consumption of 100% fruit juice can serve as a convenient means to meet daily fruit recommendations and offers many of the nutrients found in whole fruit including essential vitamins, antioxidants, and polyphenols that can contribute to a healthy dietary pattern. However, there is concern that intake of 100% fruit juice may contribute to weight gain due to the high amounts of free sugars and energy,” wrote the authors, led by Michelle Nguyen, research assistant at the University of Toronto.
As the authors point out, available data on the subject are conflicting, and recommendations in national and international guidelines are not perfectly aligned. “With the rising overweight and obesity rates in children and adults worldwide, evidence-based recommendations for 100% fruit juice consumption are needed,” wrote the authors.
What the Literature Says
To shed light on such a crucial topic, researchers conducted a literature review with a meta-analysis of prospective cohort studies lasting at least 6 months and randomized controlled trials (RCTs) lasting at least 2 weeks. The analysis included 42 studies: 17 on the pediatric population (only cohort studies; totaling 45,851 children) and 25 on the adult population (6 cohort studies and 19 RCTs; 268,095 adults involved).
In children, each daily serving of 100% fruit juice (equivalent to a glass of about 230 mL) was associated with a 0.03 increase in BMI, with a higher increase in younger children (0.15 in those under 11 years) compared with older ones (−0.001).
As for adults, the overall analysis of cohort studies did not show significant associations. Further analyses without adjusting for energy intake showed a significant association between 100% fruit juices and weight gain (0.21 kg), whereas after adjustment, an inverse association with weight gain (−0.08 kg) emerged. This finding suggests that the association may be mediated by calorie intake, wrote the researchers, adding that no association was found in the analysis of randomized controlled trials.
A Closer Look
“Our comprehensive systematic review and meta-analysis provides a novel analysis of 100% fruit juice and weight gain assessing children and adults using data from both prospective cohort studies and RCTs,” explained the authors, commenting on some of the obtained results.
Regarding the observed differences between children of different age groups, the researchers explained that a standard glass of fruit juice represents a higher proportion of the daily energy intake for a younger child compared with an older one. “Our findings are in line with American Academy of Pediatrics guidelines that children younger than 6 years should consume less than a glass of fruit juice per day,” they wrote. “Limiting intake of fruit juice among children is an important strategy for them to develop healthy weight trajectories.”
Experts also state that high-quality RCTs are needed in children and adults to explore the effect of fruit juice consumption on body weight at different intake levels and with different types of juice. “Our findings are in support of public health guidance to limit consumption of 100% fruit juice to prevent overweight and obesity,” the authors wrote.
This article was translated from Univadis Italy, which is part of the Medscape Professional Network. A version of this article appeared on Medscape.com.