Nonprescription Weight Loss Products Used by 1 in 10 Adolescents Worldwide: New Meta-Analysis

Potential for negative physical and psychological consequences is a significant public health concern, study authors say

Nearly 1 in 10 teens worldwide have used a nonprescription weight loss product, with girls significantly more likely than boys to experiment with an over-the-counter intervention (lifetime prevalence 9.5% vs 3.25%), according to a systematic review and meta-analysis just published online in JAMA Network Open.

_{©PheelingsMedia/stock.adobe.com}

More than three-quarters of the 90 articles in the analysis, comprising more than 604 000 unique participants, reported prevalent use of diet pills (77%), followed by laxatives (46%), and diuretics (20%), study authors reported. Subgroup analysis of the general adolescent population revealed that 9% reported using a nonprescription drug or dietary supplement for weight loss at least once in their lifetime; 6.0% had done so in the last year; 4.4% in the past month, and 2% reported use in the past week.

"Nonprescribed weight-loss products in children are not medically recommended for healthy weight maintenance as they do not work, are dangerous, are associated with unhealthful weight gain in adulthood, and increase the risk of being diagnosed with an eating disorder within several years of onset of use," Natasha Yvonne Hall, PharmB, MHE, of the School of Public and Preventive Health in Melbourne, Australia, and colleagues wrote. They emphasized existing data that have linked nonprescribed use of weight loss products to future low self-esteem, depression, poor nutritional intake, and substance use.

The public health concern is particularly acute as correlates between use of these products have been identified with young girls with “low self-esteem, parental influence to lose weight or dissatisfaction with weight, self-body dissatisfaction, peer groups who value thinness, and media or social media influences promoting unrealistic beauty standards,” Hall et al wrote.

"Nonprescribed weight-loss products...do not work, are dangerous, are associated with unhealthful weight gain in adulthood, and increase the risk of being diagnosed with an eating disorder within several years of onset of use."

Investigators identified 90 studies conducted in 25 countries from 6 continents between 1985 and 2023. More than half (56%) were conducted in North America. Studies included were of children and adolescents aged 18 years or younger; studies were observational, reporting on prevalence of weight loss product use over past week, month, year, or a lifetime. The definition of weight loss products was “drugs and dietary supplements that were used for weight control without a prescription or a physician’s order.” Diuretics, laxatives, and diet pills were included.

Observing that the study populations for the analysis included general adolescents as well as groups known to be at higher risk for using weight loss products (eg, those with substance use, type 1 diabetes, the LGBTQI community), the researchers conducted a second analysis that excluded studies of the latter. Their main outcome measure was the prevalence among all studies of weight loss product use over the past week, month, year, or lifetime and subgroup analysis was separated by sex, specific product types, geography, and study publication time.

ADDITIONAL FINDINGS

The total number of unique participants across studies included was 604 552. Of the 90 studies in the analysis, 77% reported nonprescribed weight loss product use in both girls and boys and 23% in girls only, according to the results. Mean age of participants ranged from 12.8 to 18.0 years. According to the researchers, most of the studies were judged of moderate or good quality.

Publication time. Of interest among the authors’ subgroup analyses was the finding that studies published before 2000 reported higher past-week prevalence (4.4%) but lower lifetime prevalence (5.1%) of weight loss products than those published after 2000 (1.5%, 10.3%). For studies published after 2010, past-week prevalence (1.1%) was lower than for either of the previous time periods, but lifetime prevalence was much higher (13.0%). Lifetime prevalence, however, has steadily increased, more than doubling since 2000.

Groups at higher risk. The team also found prevalence of diet pill use vs laxatives and diuretics, being a woman, and North American residence (vs Asia and Europe) were significantly higher, suggesting these are higher-risk populations. And, while overall use of nonprescribed weight loss products was 5.3% across all adolescents, after exclusion of high-risk participants, the prevalence ranged from 2.0% in the past week to 8.9% in their lifetime.

Of equal concern as the potential for mental and physical harm linked to use of medical products not indicated for weight loss, Hall et al wrote, “is the alarming ease of access of these products without a prescription, without a physician’s orders, and without restrictions or regulations for those 18 years or younger.”

Of equal concern as the potential for mental and physical harm linked to use of medical products not indicated for weight loss “is the alarming ease of access of these products without a prescription, without a physician’s orders, and without restrictions or regulations for those 18 years or younger.”

Among limitations of the meta-analysis, the authors include the predominance of studies from North America; the implied but not stated nonprescription status in some studies of weight-loss products; and the potential for bias in estimates and accuracy of the results based on the size of subgroup populations and range of sample sizes.

"Better understanding of the prevalence of weight-loss product use in adolescents and adolescent subgroups may allow for policy developments, further research, and targeted education strategies among particular at-risk groups,” investigators concluded. Given the individual and public health issues associated with adolescent use of nonprescription weight-loss products, interventions are urgently required to prevent and regulate” their use in this vulnerable population.

Source: Hall NY, Pathirannahalage DMH, Mihalopoulos C, Austin SB, Le L. Global prevalence of adolescent use of nonprescription weight loss products: a systematic review and meta-analysis. JAMA Netw Open. 2024;7(1):e2350940. doi:10.1001/jamanetworkopen.2023.50940