Two recent population studies add to the evidence linking higher vitamin D levels to reduced health risks
We all know that vitamin D is even more important than calcium when it comes to bone health, because it's needed to get calcium into bones.
• New population studies link low vitamin D levels to higher breast, heart, and death risks.
The findings echo those of earlier population studies from America and Europe. • Clinical trials are needed to prove a cause-effect relationship between low vitamin D and major health risks.
• Few Americans have the vitamin D blood levels recommended by leading university researchers.
• Last year, American and Austrian researchers reported results indicating that that people with low vitamin D blood levels are at greater risk of death.
Last year, American and Austrian researchers reported results indicating that that people with low vitamin D blood levels are at greater risk of death.
At about the same time, Canadian researchers published findings that affirmed earlier indications that vitamin D may protect against breast cancer.
(For more on those studies and others, see “Vitamin D Roundup: Breast Health, Mortality, and Baby Teeth,” and search our newsletter archive for “vitamin d.”)
Now, the results of a new University of Colorado analysis of health data from 3,400 Americans affirms the prior reports linking low vitamin D levels to higher death and heart risks.
And a Columbia University study published in June once again links low vitamin D levels to higher breast cancer risks.
Let's take a closer look at both of the new American studies.
National survey data links death and heart risk to low vitamin D levels
The results of a “case-control” study indicates that older people with low blood levels of vitamin D may be 2.5 times more likely to die from any cause—and three times more likely to die from heart disease.
These risks were calculated in comparison to people with adequate levels of the “sunshine and seafood” vitamin.
Fish fit the vitamin D bill; Sockeye salmon stand out
In addition to getting vitamin D from supplements, certain fish rank among the very few substantial food sources of vitamin D, far outranking milk and other D-fortified foods.
Among fish, wild Sockeye Salmon may be the richest source of all, with a single 3.5 ounce serving surpassing the US RDA of 400 IU by about 70 percent:
Vitamin D per 3.5 ounce serving*
Sockeye Salmon—687 IU
Albacore Tuna—544 IU
Silver Salmon—430 IU
King Salmon—236 IU
To arrive at the new findings, a team from the University of Colorado-Denver School of Medicine compared medical data collected from 3,488 people aged 65, including their medical records and blood test results (Ginde AA et al. 2009).
After an average of 7 years of follow-up, 1,493 people died, including 767 who died from cardiovascular disease.
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- Ginde AA, Scragg R, Schwartz RS, Camargo CA Jr. Prospective Study of Serum 25-Hydroxyvitamin D Level, Cardiovascular Disease Mortality, and All-Cause Mortality in Older U.S. Adults. J Am Geriatr Soc. 2009 Jun 22. [Epub ahead of print]
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- Wagner CL, Greer FR, Section on Breastfeeding and Committee on Nutrition. Prevention of Rickets and Vitamin D Deficiency in Infants, Children, and Adolescents Accessed online October 13, 2008 at http://www.aap.org/new/VitaminDreport.pdf