INDOOR LIFESTYLE . Office workers, homebound individuals or people who consistently wear long sleeve shirts and pants reduce the opportunity for natural vitamin D. DARK SKIN. Darker skin tends to produce less vitamin D from the sun. OBESITY. Greater amounts of fat absorb vitamin D,
inhibiting its use via blood.
GASTRIC BYPASS SURGERY . Because part of the small intestine that absorbs vitamin D is bypassed, the vitamin may not be available for use. LACK OF FAT ABSORPTION. Vitamin D is fat-soluble and needs the body’s ability to process fat properly. Diseases such as inflammatory bowel disease, Celiac disease, some liver diseases or cystic fibrosis can decrease fat absorption and may inhibit the use of vitamin D. FOOD SOURCES OF VITAMIN D
Sunlight is the most common natural source for vitamin D. Fish oils and fatty fish such as cod liver oil, herring, salmon and sardines are also natural sources. Milk is also often fortified with vitamin D.
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Having less than 30 nmol/L is too low for overall health for most people. It is rare that someone would have too much. Groups that are most likely to have lower levels of vitamin D are: ● Older adults: Skin doesn’t produce as efficiently and kidneys less able to convert to active form. ● People with dark skin: Less ability to convert vitamin D from the sun. ● People with Crohn’s disease or celiac disease: Disease inhibits absorption. ● Obese people: Body fat may prevent absorption. ● Breastfed infants: Human milk is not a good source of vitamin D. Talk with your doctor before self-prescribing a vitamin D supplement. Vitamin D supplements may interact with several types of medications. Ask your doctor if he or she recommends a blood test to determine your vitamin D level as part of routine bloodwork.
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