title: Vitamin D insufficiency in Japanese populations: from the viewpoint of the prevention of osteoporosis.
abstract: Low levels of vitamin D nutrition (i.e., vitamin D insufficiency), which potentially cause osteoporosis, have been recognized as a common health problem for elderly people in European and North American countries, but there have been no studies on the prevalence of vitamin D insufficiency in Japan until recently. The aim of this article was to review descriptive features of serum 25-hydroxyvitamin D [25(OH)D] levels and vitamin D insufficiency in Japanese subjects. Reviewing 15 studies pertaining to vitamin D nutritional status recently published for various Japanese populations revealed that: (1) the prevalence of vitamin D insufficiency in active elderly people was as low as 5% or less; (2) the prevalence of vitamin D insufficiency was much higher (up to about 50%) in inactive elderly people than in active elderly people, depending on activities of daily living (ADL); (3) frequent fish consumption helps increase serum 25(OH)D concentrations, especially in winter; and (4) vitamin D nutrition in young women was poorer than people in middle and advanced ages, which may adversely affect bone metabolism. Future studies should focus on the effects of low vitamin D status on bone mass and fractures in Japanese subjects.
authors.affiliation: Division of Social and Environmental Medicine, Department of Community Preventive Medicine, Niigata University Graduate School of Medical and Dental Sciences, 1-757 Asahimachi-dori, Niigata 951-8510, Japan. kazun@med.niigata-u.ac.jp
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Nakamura
mesh_terms: D000328:Adult; D000368:Aged; D000818:Animals; D015519:Bone Density; D005260:Female; D005399:Fishes; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000517:prevention & control; D015995:Prevalence; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood; D014808:Vitamin D Deficiency / Q000453:epidemiology*
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D