Production in Skin. Upon exposure to UVB radiation, previtamin D 3 is synthesized from 7-DHC in the skin, primarily in keratinocytes of the stratum basale and stratum spinosum layers of the epidermis. Previtamin D 3 isomerizes to form vitamin D 3 (cholecalciferol), which is subsequently transported into the circulation via a binding protein (11). Vitamin C can create a more acidic environment in the stomach and prevent the oxidization of ferrous iron to ferric iron. 10 However, in a series of 12 individuals treated with iron during intake of a regular or vitamin C–supplemented diet, 8 the effect of vitamin C on promoting iron absorption from a complete diet was far less pronounced The primary function of vitamin D is to help the body absorb calcium and phosphate, thus keeping muscles and teeth healthy and bones strong and less likely to break. However, vitamin D is also Medications used to treat acid reflux. 2. Consider taking vitamin D. Some studies suggest that increasing your vitamin D can help your body to absorb magnesium. You can eat vitamin D rich foods, like tuna, cheese, eggs, and fortified cereals. You can also absorb vitamin D by spending time out in the sunshine. It is safe to take vitamin B12, vitamin D, and magnesium together. Meanwhile, taking vitamin D with a fat-containing meal can help optimize absorption. What are the best vitamin D foods? Vitamin D 6. Eat Enough Fat. A lot of vitamins, like A, D, K, and E, are fat soluble, so they need fatty acids to absorb effectively. Sometimes you’ll find these vitamins in fatty foods (Vitamin E in Vitamin C and iron should also be taken together for two reasons: (1) Vitamin C helps your body absorb iron. (2) Vitamin C has been shown to reduce the side effects of nausea and constipation for people who are sensitive to iron. Vitamin B6, vitamin B12, and folate are B vitamins that work together to lower an amino acid called homocysteine. A In turn, reduced extraction can lead to vitamin D deficiency. In addition, people who have obesity and don't undergo gastric bypass can hold abnormally high amounts of vitamin D in their fatty tissues. While this is not a problem of fat absorption, it can still result in lowered availability of the nutrient in other areas of your body. 3vI3NU.