Nonlinear association between body fat percent and type 2 diabetes risk in Japanese adults: a retrospective cohort study.

Each 1% increase in body fat percentage was associated with a 6% increase in type 2 diabetes risk after comprehensive adjustment for confounders.

• HR = 1.06, 95% CI: 1.04–1.09
• Analysis conducted using Cox proportional hazards regression models
• Study involved 15,464 Japanese adults with a mean follow-up of 6.05 years
• BFP was identified as an independent risk factor for T2D

Restricted cubic spline analysis revealed a significant nonlinear 'hockey-stick' pattern in the association between body fat percentage and type 2 diabetes risk.

• An inflection point was identified at 21.65% body fat
• Below the threshold of 21.65%, risk rose sharply with increasing BFP (HR = 1.18, 95% CI: 1.03–1.36)
• Above the 21.65% threshold, the upward trend in risk plateaued
• Restricted cubic spline analyses were specifically employed to assess nonlinear relationships

The association between body fat percentage and type 2 diabetes risk remained robust in subgroups with normal waist circumference and absence of fatty liver disease.

• Subgroup analyses specifically included participants with normal waist circumference
• Subgroup analyses also included participants without fatty liver disease
• These findings underscore BFP's 'unique utility in detecting normal-weight obesity' according to the authors
• This suggests BFP captures metabolic risk not identified by waist circumference or fatty liver status alone

Body fat percentage surpasses body mass index in identifying metabolic risk for type 2 diabetes.

• BFP is described as 'a direct measure of adiposity' that surpasses BMI in identifying metabolic risk
• The study design was a large-scale retrospective cohort involving 15,464 Japanese adults
• Mean follow-up duration was 6.05 years
• The authors note that BFP's prospective association with incident T2D had previously remained unclear

Maintaining body fat percentage below 21.65% was proposed as a novel potential target for personalized diabetes prevention strategies.

• The 21.65% threshold was derived from the inflection point identified in restricted cubic spline analysis
• The authors characterize this as 'a novel target for personalized diabetes prevention strategies'
• The threshold is particularly relevant for individuals with normal waist circumference who may otherwise be considered low risk
• The study population consisted of Japanese adults, which may affect generalizability to other ethnic groups