Study in women links lack of vitamin D to increased levels of pro-inflammatory immune system messenger proteins
by Craig Weatherby
According to a study published earlier this year, more than three in four Americans do not have enough vitamin D in their blood… a deficiency that may promote major diseases (Ginde AA et al. 2009).
Now, two researchers from the University of Missouri have linked this widespread vitamin D deficiency to increased inflammation in healthy women… a difference they say could trigger or worsen common diseases.
They propose that their results may explain, in part, the role that the “sunshine-and-seafood” vitamin appears to play in helping deter or dampen inflammatory diseases, including heart disease, multiple sclerosis, and rheumatoid arthritis.
|Fish fit the vitamin D bill; Sockeye salmon stand out|
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
*For our full test results, click here.
“The findings reveal that low vitamin D levels negatively impact inflammation and immune response, even in healthy women,” said co-author Catherine Peterson, assistant professor in the MU College of Human Environmental Sciences. “Increased inflammation normally is found in people with obesity or chronic diseases; a small decrease in vitamin D levels may aggravate symptoms in people who are sick” (UM 2009).
Peterson and Heffernan made women cogent observations about the risks associated with even slight rises in TNF-alpha levels (Peterson CA, Heffernan ME 2009):
Researchers call for rise in RDA for vitamin D
- “TNF- alpha concentrations are increased in several disease states such multiple sclerosis (MS), inflammatory bowel disease (IBD), rheumatoid arthritis (RA), heart disease, and osteoporosis; and are often correlated with clinical impairment. Therefore, attenuating [reducing] the concentrations of circulating TNF- alpha has the potential to positively impact the risk for or treatment of such conditions.”
- “Even a slight drop in circulating TNF- alpha due to improved vitamin D status may have clinical significance. MS patients with less than 2 active brain lesions visible on magnetic resonance imagery were shown to have serum TNF-alpha concentrations that were slightly but significantly less than those with 2 or more active brain lesions.
- “Patients with active ulcerative colitis were found to have 41% greater average TNF- alpha concentrations than those with inactive disease; while, those with active Crohn's disease had TNF- alpha concentrations that were only 18 percent greater than patients with inactive Crohn’s...”
- “Increases in circulating TNF- alpha concentrations have been associated with heart disease progression.”
Peterson noted that the findings produced by her and co-author Mary Heffernan support the need to re-examine the recommended daily allowance for (RDA) vitamin D.
The RDA for vitamin D is just 200 IU for people aged 50 and younger, and only 400 IU for people 50 to 70 years old.
The guidelines, created in 1997, are being revised to reflect new research, and Peterson is confident the RDA will be increased.
As she said in a university press release, “Adequate vitamin D levels identified in this study are consistent with recent research that suggests the DRI should be increased. To improve vitamin D status and achieve its related health benefits, most people should get at least 1000 IU of vitamin D per day.”
And she cited the best ways to get more vitamin D (UM 2009):
Dr. Peterson noted that everyone should strive for a blood levels of 75 nmol/L (30 ng/mL) or more.
- “Exposing 25 percent of the skin’s surface area to 10 minutes of sunlight three days per week will maintain adequate levels in the majority of people; however, people with darkly-pigmented skin need more.”
- “Only a few foods contain vitamin D naturally, such as fatty fish; other sources are dietary supplements and vitamin-D-fortified foods, including milk and orange juice.”
She plans to test the effectiveness of vitamin D in reducing disease symptoms and reducing blood glucose levels in diabetics.
For more findings about this long overlooked, hormone-like nutrient, search our newsletter archives for "vitamin D".
- Ginde AA, Liu MC, Camargo CA Jr. Demographic differences and trends of vitamin D insufficiency in the US population, 1988-2004. Arch Intern Med. 2009 Mar 23;169(6):626-32.
- Peterson CA, Heffernan ME. Serum tumor necrosis factor-alpha concentrations are negatively correlated with serum 25(OH)D concentrations in healthy women. J Inflamm (Lond). 2008 Jul 24;5:10. doi:10.1186/1476-9255-5-10.
- University of Missouri (UM). Vitamin D Deficiency Related to Increased Inflammation in Healthy Women, MU Study Finds.April 6, 2009. Accessed at http://munews.missouri.edu/news-releases/2009/0406-peterson-vitamin-d.php