For years, 100% natural fruit juices have been hailed as a healthy choice, especially when compared to processed alternatives laden with added sugars. Traditionally, juices were even deemed equivalent to consuming a whole piece of fruit. While it’s true that they retain some nutrients from their source, the narrative is shifting.
New research, recently published in JAMA Pediatrics, sheds light on the prolonged relationship between regular fruit juice consumption and potential long-term weight gain, starting from childhood and extending into adulthood. While previous studies had presented conflicting findings, the mounting scientific evidence now allows for more robust conclusions.
Even the Dietary Guidelines for Americans have equated 100% natural fruit juice with whole fruit, recommending the limitation of free sugars but not extending this advice to those naturally present in squeezed fruit. Consequently, nearly 50% of children and adolescents consume at least one fruit juice daily, with the younger ones being the primary consumers.
For this comprehensive review and meta-analysis, searches were conducted in MEDLINE, Embase, and Cochrane databases until May 2023. A total of 42 studies were selected, comprising 17 studies in children (with 45,851 participants) and 25 studies in adults (with 268,095 participants).
The findings revealed a positive association between the consumption of 100% natural fruit juices and increased BMI in children, particularly in the younger age groups. In simpler terms, the earlier and more frequently fruit juices were consumed, the greater the associated weight gain in children.
In adults, however, the weight gain was not directly linked to juice consumption but rather to the excess calories in the form of free sugars they contain. Furthermore, age-wise analysis from this new review identified that children under 11 experienced more pronounced weight gain for each 230 ml serving compared to older children.
The detrimental effects were more substantial at younger ages, with children aged 8 and below experiencing more significant BMI increases, followed by those aged 9 to 13, and those aged 14 and above. These findings align with the recommendations of the American Academy of Pediatrics, advising that children under 6 consume less than a glass of fruit juice per day.
The suggested approach includes delaying the introduction of these juices to younger children, moderating serving sizes, and promoting the consumption of whole fruits. The authors emphasize that fruit juices, even when natural, lead to the intake of liquid sugar without the dietary matrix found in whole fruits. Juice consumption involves less fiber, no chewing effort, and consequently rapid fructose absorption by the liver.
In contrast, consuming a whole piece of fruit naturally slows down the absorption of fructose due to the chewing effort and fiber content. Moreover, it’s essential to note that producing a single serving of juice often requires several pieces of fruit. This liquid sugar is easily consumed and absorbed, with all its repercussions. As a result, medical professionals are urging a reconsideration of the role of orange juice in Spain’s diet.
