Even Nonobese Adults May Benefit From Cutting Calories

Over an average follow-up of 3 years, mean weight changes were 0.26 kg in the control group, -0.56 in the small changes group, and -2.37 kg in the large changes group (P<.001).² The researchers noted that differences among all 3 groups were significant (large changes vs control, P<.001; small changes vs control, P=.02; large changes vs small changes, P<.001).²

Compared with control, both the small-changes and the large-changes interventions significantly reduced the incidence of obesity (16.9% vs 8.6% and 7.9%, respectively; P=.02 for large changes vs control and P=.002 for small changes vs control).² The researchers also reported that a smaller percentage of participants in the large changes group, as compared with the small changes and control groups, gained 0.45 kg or more (23.6% vs 32.5% and 40.8%, respectively; P<.001 vs control and P=.02 vs small changes).²

Weight change from baseline to 2 years was also greater in the control group than in the small or large changes groups (0.54 kg vs -0.77 kg and -1.50 kg, respectively; P=.02 vs small changes and P<.001 vs large changes).²

“The findings from this trial suggest that self-regulation approaches that include frequent self-weighing have clinically significant beneficial effects on reducing weight gain and risk of obesity in young adults and indicate that a large-changes approach may be particularly effective in reducing mean weight gain over 3 years of follow-up,” the researchers concluded.

“Further follow-up is needed to determine whether effects are maintained over time and whether the large- or small-changes approach produces the best long-term outcomes.”

Clinical Implications

In an invited commentary, Tannaz Moin, MD, MBA, MSHS, of the David Geffen School of Medicine at UCLA, noted that these studies highlight the importance of prevention.

“Taken together, these 2 reports enhance our understanding of possible drivers of weight loss and propose additional angles with which to tackle the growing obesity epidemic,” Dr Moin wrote. “Both reports focused on younger, healthier adults, many of whom were of normal BMI, suggesting that weight loss interventions that buffer against possible weight gain may play an important role in the growing obesity epidemic. The approach would be akin to the primary prevention of many other chronic diseases, which is standard of care.”

Nevertheless, it remains uncertain how these weight loss interventions will perform outside of clinical trials.

“Ultimately, to be able to move the needle on the obesity epidemic, we need effective interventions that are also scalable and sustainable,” Dr Moin concluded. “Both reports in this issue of JAMA Internal Medicine describe novel and effective interventions, but the question of how they will apply in the real world remains.”

References

1. Martin CK, Bhapkar M, Pittas AG, et al; for the Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy (CALERIE) Phase 2 Study Group. Effect of Calorie Restriction on Mood, Quality of Life, Sleep, and Sexual Function in Healthy Nonobese Adults: The CALERIE 2 Randomized Clinical Trial. JAMA Intern Med. 2016. doi:10.1001/jamainternmed.2016.1189.
2. Wing RR, Tate DF, Espeland MA, et al; for the Study of Novel Approaches toWeight Gain Prevention (SNAP) Research Group. Innovative Self-Regulation Strategies to Reduce Weight Gain in Young Adults: The Study of Novel Approaches toWeight Gain Prevention (SNAP) Randomized Clinical Trial. JAMA Intern Med. 2016. doi:10.1001/jamainternmed.2016.1236.
3. Moin T. Obesity Management and Prevention: More Questions Than Answers. JAMA Intern Med. 2016. doi:10.1001/jamainternmed.2016.1211.