- A new systematic review and meta-analysis found a link between drinking 100% fruit juice and weight gain among children and adults.
- One of the reasons fruit juice contributes to weight gain is that it does not make us feel full, which leads to consuming more calories.
- The healthiest beverage swap for both children and adults is water. And if you do drink fruit juice, cut it with water or seltzer.
High in sugar and calories, health experts are finding more evidence that 100% fruit juice may cause weight gain.
In a recent systematic review and meta-analysis, researchers looked at 42 studies, which included 17 that focused on children and 25 on adults.
They discovered a link between consumption of 100% fruit juice and weight gain in children. For adults, they also found a positive association.
“This comprehensive review is the first to evaluate 100% fruit juice consumption and body weight in children and adults using both prospective cohort studies (which follow large groups of people over time to assess relationships between exposures such as diet and lifestyle with health outcomes) and RCTs (which assign groups of people to an intervention or control and examine differences in outcomes between the group),” Michelle Nguyen, lead author of the study, PhD Candidate at the Department of Nutritional Sciences Faculty of Medicine at the University of Toronto, told Healthline. “The use of both these study designs are critical to evaluate the totality of evidence.”
Whether 100% fruit juice is a healthy beverage is a question of great interest from clinicians, the general public, parents and caregivers, and policy makers.
The evidence on 100% fruit juice and weight gain has yielded mixed findings from both observational studies (prospective cohort studies) and clinical trials, Nguyen explained.
Study findings indicate that 100% fruit juice consumption was associated with weight gain in children, especially among younger children. Among prospective cohort studies in adults, they found that 100% fruit juice was associated with weight gain among studies that did not account for intake of calories in their statistical analyses (unadjusted for calories), suggesting that excess calories play a role in this association.
“Ultimately, these findings support public health guidance to limit the consumption of 100% fruit juice, especially in young children – to consume whole fruit rather than fruit juices. Our findings are in support of the AAP guidelines on 100% fruit juice consumption in children. We hope these findings will inform clinical practice guidelines and public health strategies to reduce overweight and obesity,” Nguyen stated.
How does 100% fruit juice contribute to weight gain?
The reason for weight gain is mainly due to the high sugar content.
“I find that most people have an easy time understanding how soda can lead to weight gain. But sometimes we forget how similar soda and fruit juice are,” Dr. Nate Wood, physician at the Yale School of Medicine and culinary school graduate, stated. “Although fruit juice originally comes from a whole fruit (and we know whole fruits are healthy), soda is made in a factory. Otherwise, the two drinks are largely the same: they are both very sugary water.”
Wood continued: “Although sugary water is high in calories, drinking it does not make us feel full. For this reason, the calories in sugary beverages like fruit juice are sometimes called ’empty calories.’ Drinking these calories frequently is one common way that we end up consuming more energy than our bodies need. This extra energy is then converted to body fat, which leads to weight gain.”
However, it is important to note there are other factors that need to be taken into consideration to know what’s causing the increase in BMI.
“The authors of this study looked at studies that compared fruit juice to a non-caloric beverage, so it makes sense that the drink that has calories will be linked with a higher BMI,” said Natalie Rizzo, MS, RD, author of Planted Performance. “And correlation doesn’t equal causation. This means that just because kids who drink fruit juice tend to gain BMI, it’s impossible to know if it’s from the fruit juice alone.”
In addition, the consumption of liquid calories has been shown to result in greater weight gain compared to the consumption of solid calories, Nguyen explained.
Furthermore, “the lack of dietary fiber in fruit juice compared to its whole fruit form can result in decreased satiety and overconsumption of these beverages. In children specifically, studies have indicated that early introduction of fruit juice may lead to increased risk of overweight and obesity due to increased preference for sweet food,” said Nguyen. “Thus, delaying the introduction of 100% fruit juice in young children, moderating serving sizes, and choosing whole fruit rather than fruit juice is recommended.”
This raises the question: “is it advisable to have the actual fruit and skip on the juice?”
“The answer is nuanced because some kids refuse fruit, but they will accept 100% fruit juice. And 100% fruit juice is made from fruit and has no added sugar, so a kid who drinks it is still getting plenty of vitamins and minerals from drinking the juice,” Rizzo explained. “As a matter of fact, older research states that kids who drink 100% fruit juice have higher intake and adequacy of dietary fiber, vitamin C, magnesium, and potassium. But, if a kid is willing to eat fruit instead of drinking juice, then it’s a good idea to have them do so.”
Nutritional guidelines for children and adults regarding fruit juice
Children under 12 months of age should not be given any fruit juice, Wood explained. For children and adults above 12 months of age, it’s reasonable to occasionally consume fruit juice as a sweet treat.
“The key way to look at fruit juice is a sweet treat, not a health food,” said Wood. “It’s not the same as eating a serving of whole fruit. Fruit juice is not essential for children in the same way that it’s not essential for adults. We’re certainly better off opting for whole fruit.”
Limiting fruit juice consumption is advised.
“Kids tend to be more selective in what they will and will not eat,” said Rizzo. “Because of that, they will refuse other healthy options and over consume certain beverages, like juice. So for kids, I would recommend limiting juice intake if they are neglecting other things, like milk or water.”
Adults have more knowledge of nutrition and are able to make more informed choices, so they can limit themselves to a serving of juice, rather than over consume. Both children and adults don’t need to fully avoid juice, but they should limit the serving size, Rizzo added.
Healthy beverage replacements
“Water is always the best choice for kids and adults,” Rizzo stated. “And milk is important for kids to get calcium and Vitamin D. If a kid wants fruit juice, makes sure it’s 100% juice and limit the serving to 4 ounces per day.”
Unsweetened, fortified soy milk is another option rich in calcium and vitamin D for children who can’t have dairy or whose families prefer plant-based options.
The most important thing when selecting juice is to opt for 100% juice, Wood stated. There are many products out there that look like juice but are actually a juice cocktail made with extra sugar. It’s also important to note that some fruit juices are higher in sugar than others.
For instance, grape juice can have 36 grams of sugar in a single cup, whereas orange juice has about 21 grams of sugar per cup.
“I often tell folks to cut their juice with a little still or sparkling water,” said Wood. “For instance, you could add 4 ounces of grape juice to a lime seltzer. It’s fizzy and fun, slightly sweet, has a zip from the lime, and contains much less sugar than a glass of pure grape juice would.”
He added: “Another option would be to take whole fruit, muddle it in the bottom of your glass, and then add some water or seltzer. This works particularly well with berries or slices of citrus — lemon, grapefruit, and lime.”
Takeaway
According to a new systematic review and meta-analysis, there is a positive association between drinking 100% fruit juice and weight gain among children and adults.
Fruit juice is a contributing factor to weight gain because it is high in sugar and calories. It also doesn’t make us feel full, which leads to drinking too much.
Health experts suggest switching to water for both children and adults.
