Written by Greg Arnold, DC, CSCS.
In a new study, researchers analyzed data on over 3,400 patients aged 65 and older who participated in the Third National Health and Nutrition Examination Survey (1). The survey took place from October 1988 to October 1994, and was followed by an analysis of the patients through December 31, 2000. Patient examinations included a physical exam, blood and urine samples, and diet information. The researchers divided the patients into five different groups based on the blood levels of vitamin D:
- Group 1: <25.0 nmol/L
- Group 2: 25.0–49.9 nmol/L
- Group 3: 50.0–74.9 nmol/L
- Group 4: 75.0–99.9 nmol/L
- Group 5: ≥100.0 nmol/L
The researchers found “a significant inverse association between [vitamin D blood levels] and mortality risk in older adults.” Compared to patients with highest vitamin D blood levels (≥ 100 nmol/L), the risk for cardiovascular death (heart attack and stroke) increased by 20% for those with vitamin D levels of 75.0–99.9 nmol/L, increased by 26% for those in 50.0–74.9 nmol/L group, increased by 54% for those in the 25.0–49.9 nmol/L group, and increased by 136% for those in the 25.0 nmol/L group.
For all other causes of death other than heart attack and stroke, the risk was still significant compared to the highest vitamin D blood levels (11% increased risk for the 75.0–99.9 nmol/L group, a 16% increased risk for those in 50.0–74.9 nmol/L group, a 42% increased risk for both the 25.0–49.9 nmol/L and 25.0 nmol/L groups).
The researchers suggested several ways vitamin D is such a benefit to the cardiovascular system that included “beneficial changes” in heart function (2), blood pressure (3), arterial function (4) and inflammatory processes (5). They concluded that “This study demonstrated a significant inverse association between baseline [vitamin D] levels and mortality risk in older adults.”
Source: “Prospective Study of Serum 25-Hydroxyvitamin D Level, Cardiovascular Disease Mortality, and All-Cause Mortality in Older U.S. Adults” in the October 2009 issue of the Journal of the American Geriatrics Society. Posted October 16, 2009.
Greg Arnold is a Chiropractic Physician practicing in Danville, CA. You can contact Dr. Arnold directly by emailing him at mailto:PitchingDoc@msn.com or visiting his web site at www.CompleteChiropracticHealthcare.com
References:
- NHANES III data available at http://www.cdc.gov/nchs/products/elec_prods/subject/nhanes3.htm
- Weishaar RE, Kim SN, Saunders DE et al. Involvement of vitamin D3 with cardiovascular function. III. Effects on physical and morphological properties. Am J Physiol 1990;258:E134–E142.
- Forman JP, Giovannucci E, Holmes MD et al. Plasma 25-hydroxyvitamin D levels and risk of incident hypertension. Hypertension 2007;49:1063–1069.
- Sugden JA, Davies JI, Witham MD et al. Vitamin D improves endothelial function in patients with type 2 diabetes mellitus and low vitamin D levels. Diabet Med 2008;25:320–325.
- Willheim M, Thien R, Schrattbauer K et al. Regulatory effects of 1alpha,25-dihydroxvitamin D3 on the cytokine production of human peripheral blood lymphocytes. J Clin Endocrinol Metab 1999;84:3739–3744.