Subcutaneous adipose cell size and distribution: relationship to insulin resistance and body fat

Obesity (Silver Spring). 2014 Mar;22(3):673-80. doi: 10.1002/oby.20209. Epub 2013 Dec 17.


Objective: Metabolic heterogeneity among obese individuals may be attributable to differences in adipose cell size. We sought to clarify this by quantifying adipose cell size distribution, body fat, and insulin-mediated glucose uptake in overweight to moderately-obese individuals.

Methods: A total of 148 healthy nondiabetic subjects with BMI 25-38 kg/m2 underwent subcutaneous adipose tissue biopsies and quantification of insulin-mediated glucose uptake with steady-state plasma glucose (SSPG) concentrations during the modified insulin suppression test. Cell size distributions were obtained with Beckman Coulter Multisizer. Primary endpoints included % small adipose cells and diameter of large adipose cells. Cell-size and metabolic parameters were compared by regression for the whole group, according to insulin-resistant (IR) and insulin-sensitive (IS) subgroups, and by body fat quintile.

Results: Both large and small adipose cells were present in nearly equal proportions. Percent small cells was associated with SSPG (r = 0.26, P = 0.003). Compared to BMI-matched IS individuals, IR counterparts demonstrated fewer, but larger large adipose cells, and a greater proportion of small-to-large adipose cells. Diameter of the large adipose cells was associated with % body fat (r = 0.26, P = 0.014), female sex (r = 0.21, P = 0.036), and SSPG (r = 0.20, P = 0.012). In the highest versus lowest % body fat quintile, adipose cell size increased by only 7%, whereas adipose cell number increased by 74%.

Conclusions: Recruitment of adipose cells is required for expansion of body fat mass beyond BMI of 25 kg/m2 . Insulin resistance is associated with accumulation of small adipose cells and enlargement of large adipose cells. These data support the notion that impaired adipogenesis may underlie insulin resistance.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adipocytes / cytology*
  • Adipogenesis
  • Adult
  • Biopsy
  • Blood Glucose / metabolism
  • Body Mass Index
  • Cell Size
  • Female
  • Healthy Volunteers
  • Humans
  • Insulin / metabolism
  • Insulin Resistance*
  • Linear Models
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Obesity / metabolism
  • Overweight / metabolism
  • Subcutaneous Fat / cytology*
  • Subcutaneous Fat / metabolism
  • Triglycerides / metabolism


  • Blood Glucose
  • Insulin
  • Triglycerides