An evaluation of the relative contributions of exposure to sunlight and of diet to the circulating concentrations of 25-hydroxyvitamin D in an elderly nursing home population in Boston

Am J Clin Nutr. 1990 Jun;51(6):1075-81. doi: 10.1093/ajcn/51.6.1075.


We investigated the vitamin D status of a Caucasian elderly population in a long-term-care facility in Boston. Comparison was made with a group of free-living elderly people. The sunlight exposure of residents was monitored and its effect on the serum concentrations of 25-hydroxyvitamin D [25(OH)D] was compared with contributions from diet and multivitamins. Seasonal changes in serum 25(OH)D concentrations caused by sunlight exposure were greatest in the free-living subjects and declined in magnitude as the mobility of the volunteers decreased. Diet failed to provide an adequate amount of vitamin D for volunteers who had minimal outdoor activity. Use of a multivitamin supplement containing 10 micrograms (400 IU) vitamin D maintained serum 25(OH)D concentrations greater than 37.5 nmol/L.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Activities of Daily Living
  • Aged
  • Aged, 80 and over
  • Aging / blood*
  • Boston
  • Diet*
  • Evaluation Studies as Topic
  • Female
  • Homes for the Aged*
  • Humans
  • Hydroxycholecalciferols / administration & dosage
  • Hydroxycholecalciferols / blood*
  • Male
  • Nursing Homes*
  • Parathyroid Hormone / blood
  • Seasons
  • Sunlight*


  • Hydroxycholecalciferols
  • Parathyroid Hormone