Energy restrictive diets improve cardiometabolic, mental health among adolescents
Click Here to Manage Email Alerts
Key takeaways:
- Both diets yielded similar improvements in BMI, blood pressure and cholesterol, among other measures.
- Participants experienced reduced depression symptoms within 4 weeks.
Intermittent and continuous energy restriction diets both improved cardiometabolic measures and reduced symptoms of depression and disordered eating among adolescents with obesity, according to findings published in JAMA Pediatrics.
Researchers published two studies from the Fast Track to Health clinical trial, which took place between Jan. 31, 2018, and March 31, 2023, at two children’s hospitals in Australia. The parallel controlled randomized trial included 141 adolescents (50.4% boys; median age, 14.8 years; interquartile range [IQR], 12.9-17.9 years) with a BMI of 30 or higher and at least one cardiometabolic complication.
All participants spent the first 4 weeks consuming a very low energy diet (800 kcal per day). When they reached week 5, the researchers assigned 70 participants to a continuous energy restriction diet (1,430 to 1,900 kcal per day based on age) and 71 participants to an intermittent energy restriction diet that included 3 days per week of very low caloric intake (600 to 700 kcal per day) and 4 days of eating based on Australian Dietary Guidelines. Adolescents continued their assigned diet for 1 year, or until they met their calculated healthy body weight.
Cardiometabolic outcomes
Natalie B. Lister, PhD, senior research fellow and research dietitian at The University of Sydney Children’s Hospital at Westmead Clinical School, and colleagues compared cardiometabolic measures to determine the efficacy of each diet. The primary outcome was the BMI z score. The researchers also evaluated blood pressure, triglycerides, cholesterol, glucose and insulin levels among the participants.
Out of all participants, 97 (68.8%) completed the 52-week study, including 43 from the intermittent fasting group (IER) and 54 from the continuous energy restriction group (CER).
The IER and CER groups had similar changes in estimated marginal means (EMM) for BMI z scores at the end of the study (–0.28; 95% CI, –0.37 to –0.2 vs. –0.28; 95% CI, –0.36 to –0.2, respectively).
Many participants in both groups saw reductions in blood pressure, cholesterol, triglycerides and fasting plasma insulin; there was no significant difference between groups, according to the researchers.
The proportion of participants with insulin resistance decreased in the first 16 weeks of the study, but only the CER group maintained these results at 52 weeks.
“We thought the intermittent energy restriction group would have more weight loss based on our pilot study suggesting young people liked and would continue with the low energy days,” Lister told Healio. “Our result is consistent with what was found in adult trials.”
Mental health improvements
Among the same cohort, the researchers evaluated participants’ mental health outcomes. At week 4, week 16 and week 52, they screened participants for depression using the Center for Epidemiologic Studies Depression Scale 10-Item Version for adolescents, which is scored from 0 to 30. A score of 8 or higher is associated with depression symptoms.
The researchers also screened the adolescents for disordered eating through the Eating Disorder Examination Questionnaire (EDE-Q) and Binge Eating Scale (BES). The EDE-Q is scored from 0 to 6, with a cutoff of 2.8. BES scores of 18 to 26 are considered mild or moderate binge eating, and a score of 27 or higher is associated with severe binge eating.
“Some previous studies have reported on the onset of disordered eating during weight management interventions,” Hiba Jebeile, PhD, MNutrDiet, BMedSci, BBus research fellow and research dietician at The University of Sydney Children’s Hospital at Westmead Clinical School, told Healio. “Our formal screening and monitoring process has allowed us to identify how many adolescents may experience these symptoms.”
Participants’ depression symptoms decreased by week 4 and were still present at week 52 in the IER and CER groups (change in EMM, –2.7; 95% CI, –4.95 to –0.45; and change in EMM, –3.87; 95% CI, –5.98 to –1.77). The researchers reported no significant difference between the two groups.
Eating disorder symptoms also decreased by week 4 and continued through week 52. The IER group saw a score reduction of –0.63 (95% CI, –0.97 to –0.26), and the CER group’s scores changed by –0.56 (95% CI, –0.89 to –0.22). There was no significant difference between the groups.
Both groups had lower BES scores at week 4, but by week 52, only the IER group had significantly reduced symptoms (–3.72; 95% CI, –6.2 to –1.24 vs. –0.38; 95% CI, –2.71 to 1.96).
About half of participants (47.5%) reported adverse events. The most common were COVID-19 infection (35.4%), illness or injury unrelated to the intervention (22.9%) and gastrointestinal disturbances (15.6%). Six participants experienced eight serious adverse events, of which two may have been related to the trial — one participant developed gallstones, and another was diagnosed with anorexia nervosa.
“Clinicians should be aware that some adolescents with obesity who are seeking weight management may also have symptoms of depression or disordered eating, including binge eating,” Jebeile said. “It is important for these to be assessed and addressed as part of obesity care.”
The researchers concluded that IER is an acceptable alternative to CER, which allows adolescents more choices for pursuing weight loss.
Lister said she and colleagues will have more studies coming from the trial, including a 2-year follow-up.
“Without studies such as Fast Track, there will be very limited evidence from which to offer solutions for adolescents with weight concerns, and they will resort to using social media and influencers for advice,” Lister said.
References:
- Jebeile H, et al. J Nutr. 2019;doi:10.1093/jn/nxz049.
- Jebeile H, et al. JAMA Pediatr. 2024;doi:10.1001/jamapediatrics.2024.2851.
- Jebeile H, et al. JAMA Pediatr. 2019;doi:10.1001/jamapediatrics.2019.2841.
- Jebeile H, et al. Obes Rev. 2019;doi:10.1111/obr.12866.
- Lister NB, et al. JAMA Pediatr. 2024;doi:10.1001/jamapediatrics.2024.2869.
Collapse
Read more about
Click Here to Manage Email Alerts