The beginning of year 2009 through March, the National Nutrition Month, leading up to the American Diabetes Alert Day of March 24 saw many studies came out in favor of the "Happy Vitamin" D. Researchers from Bristol University, UK, found that moms who get more sunshine and vitamin D during pregnancy have taller children with stronger and thicker bones than those moms who get less. The study followed moms that delivered either late summer or early spring. Babies born in late summer were slightly taller with thicker bones. Scientist Jon Tobias thinks that anything that affects early bone development is significant in regards to preventing osteoporosis later. Vitamin D3 is produced in the body upon sun exposure and aids in the absorption of calcium, magnesium and phosphorus that all aid in tissue and bone maintenance and metabolic actions. www.guardian.co.uk
In the Journal of Clinical Endocrinology & Metabolism, researchers from the University of Manchester report: - "Our study found that vitamin D is positively related to muscle power, force, velocity and jump height in adolescent girls." supporting the above findings on the bone and muscle strengthening benefits of vitamin D.
Calcium and vitamin D have also been shown to improve insulin levels and to protect against diabetes. In the Journal of Nutrition1, Tianying Wu, Walter C. Willet, and Edward Giovannucci from the Harvard School of Public Health wrote: -" The results suggest that calcium intake and systematic vitamin D status, after adjustment for intake of dairy products, is associated with decreased insulin secretion." Data from the Nurses' Health Study was used showing the benefits from increased calcium and vitamin D intake. However no benefit was found when considering dairy intake. This was in contrast to earlier studies. Diabetes is growing rapidly; 19 million Europeans and 20 million Americans suffer from diabetes.
With diabetes also being connected to a high incidence of perinatal and postpartum depression in especially low -- income mothers, nutritional efforts have to be addressed especially in regards to vitamin D and calcium. Omega fatty acids also play an important role in diabetes and depression. Postpartum depression has been shown to affect babies negatively and should be prevented.
Diabetes is in addition associated with obesity and a new study by the Medical College of Georgia's Yanbin Dong and Inger Stallman-Jorgensen, presented at the American Heart Association's Joint 49th Conference on Cardiovascular Disease Epidemiology and Prevention and Nutrition, Physical Activity and Metabolism, is showing that higher intakes of vitamin D again is linked with less overall body fat and especially lower abdominal fat in kids. African - American girls had the lowest Vitamin D levels and are at increased risk of osteoporosis and obesity. Vitamin D comes in 2 forms: D3 which is produced from sun exposure and the most bioactive and D2 found in foods like liver, fatty fish and fortified milk. Stallman-Jorgensen said: -"As humans, our largest source of vitamin D should be the sun. But we don't spend enough time outdoors to get enough sun exposure and when we do, we're often covered up and wearing sunscreen."
Vitamin D is also according to Dr. Christine Olson, professor of nutrition at Cornell University in NY, linked to a mother's weight gain during pregnancy and is therefore associated with increased likelihood of childhood obesity and diabetes too, if mom gains too much. (More than 25-35 lbs.) Experts are warning that preventing obesity starts before conception with mom's weight. The trend toward bigger babies is of concern to experts. Today babies are born 59% more likely to be overweight than 20 years ago. Even the child's father's weight can predict an overweight baby. ACOG has more on this.
Oxford-based researchers, in collaboration with researchers from the University of British Columbia in Canada also found that Supplements of vitamin D and sunshine at 'critical time periods' may be key to reducing the risk of multiple sclerosis3.
With these studies adding to a growing body of science linking vitamin D-deficiency to osteoporosis, muscle weakness, fractures, several common cancers, autoimmune diseases, infectious diseases and cardiovascular diseases, the FDA has just allowed for vitamin D fortification of soy-based foods (Food Additives Rule 21 CFR part 172). However, your best source is still the sun so, with spring here and summer around the corner, Vitamin D will be plentiful. To safely get sufficient vitamin D Caucasians should get 10-15 minutes of daily unprotected sunshine (no sun screen). Dark skinned people need up to 45 minutes of daily sunshine to produce enough vitamin D due to the higher melanin content in their skin. The sun does dry our skin so it is always prude to protect your face from the sun while any other body part soaks up the sun.
-Birgitta Lauren www.expectingfitness.com
1 Journal of Nutrition 2009, Volume 139, Pages 547-554, doi:10.3945/jn.108.089920 "Plasma C-Peptide Is Inversely Associated with Calcium Intake in Women and with Plasma 25-Hydroxy Vitamin D in Men" - Authors: T. Wu, W.C. Willett, E. Giovannucci
2 JAMA 2009;301(8):842-847
3 PLoS Genetics 5(2): e1000369. doi:10.1371/journal.pgen.1000369 "Expression of the multiple sclerosis-associated MHC class II allele HLA-DRB1*1501 is regulated by Vitamin D", Authors: S.V. Ramagopalan, N.J. Maugeri, L. Handunnetthi, Lincoln MR, Orton S-M, et al.