Abstract
Vitamin D, the sunshine vitamin, has received much attention for its roles in bone health and nonskeletal roles such as cell growth, cell differentiation, immune function, and several chronic disorders. While evidence exists for some roles, many other attributes are continuing to be studied and debated. Deficiency is common worldwide, including in the USA. Sunlight is a primary source for the vitamin, but adequate exposure to sunlight on a sustained basis is not practical. Dietary food sources are limited in vitamin D, barring fatty fish and fortified foods. Hence, supplements may be the practical source for ensuring optimal intake and for treatment of deficiency. Clinical manifestations of deficiency range from being asymptomatic to musculoskeletal pain, gait disturbances, and fracture. Vitamin D is a critical requirement for musculoskeletal health, a noncontroversial fact. But deficiency has also been linked to several health disorders including cancer, cardiovascular disease, heart failure, infections, cognition, depression, and more. Serum 25 (OH) D is the best measure of vitamin D status and is the storage form of the vitamin, whereas, 1,25(OH)2D is the physiological or active form. Vitamin D is necessary for maximal calcium and phosphorus absorption via the gut and other organs. Deficiency is common in geriatric individuals due to several factors, including decreased sunlight exposure, inefficient skin synthesis, and low intake. Newer guidelines from several organizations have commented on what constitutes adequate vitamin D levels, as well as inadequacy, and largely agree on a level of 20 ng/ml or higher and recommend a daily intake of 800 IU/d for adults over the age of 70 years. Dosages and approaches for addressing vitamin D deficiency vary, based on a given organization, and are listed. The preferred means of correction of deficiency is through supplements, rather than diet or sunlight exposure. Data from studies on vitamin D deficiency and supplementation in relation to outcomes are succinctly provided in tables.
| Original language | English (US) |
|---|---|
| Title of host publication | Geriatric Gastroenterology, Second Edition |
| Publisher | Springer International Publishing |
| Pages | 653-682 |
| Number of pages | 30 |
| ISBN (Electronic) | 9783030301927 |
| ISBN (Print) | 9783030301910 |
| DOIs | |
| State | Published - Jan 1 2021 |
Keywords
- 1, 25 dihydroxy vitamin D
- 25 hydroxy vitamin D
- Bariatric surgery and vitamin D
- Calcitriol
- Causes of vitamin D deficiency
- Clinical manifestations of vitamin D deficiency
- Fortification of foods with vitamin D
- Manifestations of vitamin D deficiency
- Normal levels of vitamin D
- Osteoblast
- Osteoclast
- Osteomalacia
- Osteoporosis
- Sunlight and vitamin D
- Treatment of vitamin D deficiency
- VDR receptor
- Vitamin D
- Vitamin D and antineoplastic effects
- Vitamin D and calcium
- Vitamin D and calcium
- Vitamin D and cancer
- Vitamin D and diabetes mellitus
- Vitamin D and fall
- Vitamin D and gastric bypass surgery
- Vitamin D and gastrointestinal disorders
- Vitamin D and heart disease
- Vitamin D and hypertension
- Vitamin D and immunomodulation
- Vitamin D and liver disease
- Vitamin D and obesity
- Vitamin D and psoriasis
- Vitamin D content of foods
- Vitamin D deficiency
- Vitamin D deficiency and falls
- Vitamin D levels
- Vitamin D metabolism
- Vitamin D requirements
- Vitamin D sources
- Vitamin D2
- Vitamin D3
ASJC Scopus subject areas
- General Medicine
