Associations of Outdoor Temperature, Bright Sunlight, and Cardiometabolic Traits in Two European Population-Based Cohorts

J Clin Endocrinol Metab. 2019 Jul 1;104(7):2903-2910. doi: 10.1210/jc.2018-02532.


Context: Seasonal variation in cold and light exposure may influence metabolic health.

Objective: We assessed the associations of bright sunlight and outdoor temperature with measures of glucose and lipid metabolism in two populations of middle-aged European subjects.

Design: Cross-sectional study.

Setting: Two population-based European cohorts.

Participants: Middle-aged nondiabetic subjects from the Oxford Biobank (OBB; N = 4327; mean age, 41.4 years) and the Netherlands Epidemiology of Obesity (NEO) study (N = 5899; mean age, 55.6 years).

Interventions: Data on outdoor bright sunlight and temperature collected from local weather stations.

Main outcome measures: Insulin resistance and fasting lipid levels. Multivariable regression analyses were adjusted for age, sex, percentage body fat, season, and either outdoor temperature or bright sunlight.

Results: In the OBB cohort, increased bright sunlight exposure was associated with lower fasting insulin [-1.27% (95% CI, -2.09 to -0.47%) per extra hour of bright sunlight], lower homeostatic model assessment for insulin resistance (-1.36%; 95% CI, -2.23 to -0.50), lower homeostatic model assessment for β-cell function (-0.80%; 95% CI, -1.31 to -0.30), and lower triglyceride (-1.28%; 95% CI, -2.07 to -0.50) levels. In the NEO cohort generally unidirectional but weaker associations were observed. No associations between outdoor temperature and measures of glucose or lipid metabolism were detected following adjustment for bright sunlight.

Conclusions: Bright sunlight, but not outdoor temperature, might be associated with increased insulin sensitivity and lower triglyceride levels.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipose Tissue
  • Adult
  • Blood Glucose / metabolism
  • Cholesterol, HDL / metabolism
  • Cholesterol, LDL / metabolism
  • Cross-Sectional Studies
  • England
  • Female
  • Humans
  • Insulin / metabolism
  • Insulin Resistance*
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Netherlands
  • Overweight / metabolism
  • Seasons
  • Sunlight*
  • Temperature*
  • Triglycerides / metabolism
  • Weather
  • White People


  • Blood Glucose
  • Cholesterol, HDL
  • Cholesterol, LDL
  • Insulin
  • Triglycerides