What Is Vitamin D?
Vitamin D is a fat-soluble vitamin that helps the body absorb dietary calcium and phosphorus from the intestines and suppresses the release of parathyroid hormone, a hormone that causes bone resorption. This serves to keep the bones healthy. Vitamin D is also believed to improve muscle and immune function.
Vitamin D is made in the skin when it is exposed to sunlight. Vitamin D is also naturally occurring in certain foods such as fatty fish, cod liver oil, and eggs. It is also found on fortified foods such as cow’s milk.
What Are the Benefits of Taking Vitamin D?
The benefits of taking vitamin D include:
- Bone health and reduced risk of osteoporosis
- Strengthens muscles
- Reduces inflammation
- Helps with immune system function
- Aids in glucose (sugar) metabolism which may help prevent diabetes
- May help reduce the risk of death from breast, colorectal, pancreatic, and prostate cancers
- Helps promote heart health and lowers the risk of cardiovascular disease
- May help treat high blood pressure (hypertension)
- May help treat depression
- May reduce the risk of contracting multiple sclerosis (MS) and, once MS is present, decrease the risk of relapse and slow the disease’s progression
- May help with weight loss
- Lowers the risk of tooth decay and gum disease
What Foods Are Good Sources of Vitamin D?
Foods that are good sources of vitamin D include:
- Meat and poultry
- Beef liver
- Chicken breast
- Ground beef
- Mushrooms – white and portabella
- Dairy products
- Milk, vitamin D fortified
- Cheddar cheese
- Cod liver oil
- Plant-based milks (e.g. soy, almond, oat), vitamin D fortified
- Ready-to-eat cereals, vitamin D fortified
Exposure to sunlight is also another source for vitamin D but too much sun exposure can lead to sunburns, premature skin aging, eye damage, heat exhaustion or heat stroke, or skin cancer. Talk to your doctor about how much sun exposure you may need and how to get exposure safely.
What Are Risks of Taking Vitamin D?
Excess amounts of vitamin D are toxic. Vitamin D toxicity is unlikely to occur from excessive sun exposure or by eating foods high in vitamin D, but can happen from taking vitamin D supplements inappropriately or in excessive amounts. Excess vitamin D can lead to excess high blood calcium levels (hypercalcemia) and excess calcium in the urine (hypercalciuria).
Hypercalcemia can lead to symptoms such as:
- Muscle weakness
- Neuropsychiatric disturbances
- Loss of appetite
- Increased urine production
- Excessive thirst
- Kidney stones
Severe cases of vitamin D toxicity can lead to: