Vitamin D deficiency affects over 1 billion people (including children and adults) worldwide. Vitamin D is essential for bone strength. This fat-soluble vitamin functions to enhance the absorption of calcium into the bloodstream. Calcium is a key nutrient for our body, bones, and teeth. In individuals with low vitamin D levels, the bones become brittle and are prone to rickets (in children), and osteomalacia and osteoporosis (in adults). Not only are the bones weakened by the lack of vitamin D, but the gastrointestinal, cardiovascular and endocrine (causing type 2 diabetes) systems are compromised as well. Other than increasing vitamin D intake in the diet and exposing the skin to sunlight, a probiotic supplement containing L. reuteri NCIMB 30242 is proven effective at boosting the vitamin D blood levels.
How L. reuteri NCIMB 30242 increases vitamin D levels?
- L. reuteri NCIMB 30242 raises 7-dehydrocholesterol (7-DHC)
- L. reuteri NCIMB 30242 owns a unique bile salt hydrolase (BSH) activity. While the enzyme BSH reduces the cholesterol levels, the levels of an animal sterol called 7-DHC are also elevated in response to BSH activity. 7-DHC (present in the skin and other tissues) is a precursor to vitamin D and is converted to vitamin D on exposure to sunlight. 
Lactobacilli lower the intestinal pH
Vitamin D requires an acidic medium to be absorbed. The acid in the lactic acid bacteria reduces the pH of the intestine, which enhances the absorption of the vitamin D ingested in the diet. 
L. reuteri NCIMB 30242 enhances the expression of Vitamin D Receptor
Also recognized, is the role of L. reuteri NCIMB 30242 in augmenting the expression and activity of the vitamin D receptor (VDR). VDR facilitates the body to respond to vitamin D appropriately, increasing its uptake by the intestinal cells.  The VDR is also critical to maintaining a state of balance in the gut, warding off the bad bacteria, blocking inflammation, and preserving the integrity of the intestinal lining.  A dysfunctional VDR and consequently a paucity of vitamin D may thus provoke intestinal damage and inflammatory bowel disease.