How Helpful Are School-Based BMI Measurements?

KA Madsen et al. JAMA Pediatr. Published online November 16, 2020. doi:10.1001/jamapediatrics.2020.4768.Full text link: Effect of School-Based Body Mass Index Reporting in California Public Schools

Methods:  Cluster randomized clinical trial. The Fit Study (2014-2017) randomized 79 California schools (n=28 641 students) to BMI screening and reporting (group 1), BMI screening only (group 2), or control (no BMI screening or reporting [group 3]) in grades 3 to 8. The setting was California elementary and middle school

Key findings:

  • Among 6534 of 16 622 students with a baseline BMI in the 85th percentile or higher (39.3%), BMI reporting had no effect on BMI z score change (−0.003; 95% CI, −0.02 to 0.01 at 1 year and 0.01; 95% CI, −0.02 to 0.03 at 2 years)
  • Weight dissatisfaction increased more among students having BMI screened at school (8694 students in groups 1 and 2) than among control participants (5674 students in group 3).

My take: Tackling obesity will require a lot more than measuring BMIs. An interesting follow-up study would be to see if schools who reported BMIs were more likely to take other measures, such as providing nutritional counseling, improving school lunch selection, and providing opportunity for more activity/exercise.

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Weight Loss Improves NASH

A recent study ( helps confirm the notion that the most effective therapy for nonalcoholic steatohepatitis is weight loss. (From Rohit Kohli twitter feed).


Background & Aims

It is not clear how weight loss affects histologic features of liver in patients with nonalcoholic steatohepatitis (NASH). We examined the association between the magnitude of weight loss through lifestyle modifications and changes in histologic features of NASH.


We conducted a prospective study of 293 patients with histologically proven NASH who were encouraged to adopt recommended lifestyle changes to reduce their weight over 52 weeks, from June 2009 through May 2013, at a tertiary medical center in Havana, Cuba. Liver biopsies were collected when the study began and at week 52 of the diet, and analyzed histologically.


Paired liver biopsies were available from 261 patients. Among 293 patients who underwent lifestyle changes for 52 weeks, 72 (25%) achieved resolution of steatohepatitis, 38 (47%) had reductions in NAFLD activity scores (NAS), and 56 (19%) had regression of fibrosis. At week 52, 88 subjects (30%) had lost 5% or more of their weight. Degree of weight loss was independently associated with improvements in all NASH-related histological parameters (odds ratios, 1.1–2.0;P<.01). A higher proportion of subjects with 5% weight loss or more had NASH resolution (51/88, 58%) and a 2-pt reduction in NAS (72/88, 82%) than subjects that lost less than 5% of their weight (P<.001). All patients who lost 10% of their weight or more had reductions NAS, 90% had resolution of NASH, and 45% had regression of fibrosis. All patients who lost 7%−10% of their weight and had few risk factors also had reduced NAS. In patients with baseline characteristics that included female sex, body mass index ≥35, fasting glucose >5.5 mmol/L, and many ballooned cells, NAS scores decreased significantly with weight reductions of 10% or more.


A greater extent of weight loss, induced by lifestyle changes, is associated with the level of improvement in histologic features of NASH. The highest rates of NAS reduction, NASH resolution, and fibrosis regression occurred in patients with weight losses of 10% or more.