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 may help with weight loss, decreasing body fat, and limiting weight gain over time.
- One study found that overweight and obese women who got adequate vitamin D over a one-year period lost more weight than the women who did not get adequate vitamin D
- Another study showed that overweight and obese women given vitamin D supplements for 12 weeks had decreased body fat, though no weight loss
- A 4-½-year study in elderly women found that higher levels of vitamin D were associated with less weight gain over time
More study is needed to determine exactly why or how vitamin D may help with weight loss.
Other benefits of taking vitamin D include:
- Bone health and reduced risk of osteoporosis
- Strengthens muscles
- Helps with immune system function
- Reduces inflammation
- Aids in glucose (sugar) metabolism which may help prevent diabetes
- Helps promote heart health and lowers the risk of cardiovascular disease
- Lowers the risk of tooth decay and gum disease
- May help reduce the risk of death from breast, colorectal, pancreatic, and prostate cancers
- May help treat depression
- May help treat high blood pressure (hypertension)
- 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
What Foods Are Good Sources of Vitamin D?
Foods that are good sources of vitamin D include:
- Vegetables
- Mushrooms – white and portabella
- Seafood
- Salmon
- Sardines
- Trout
- Tuna
- Dairy products
- Milk, vitamin D fortified
- Cheddar cheese
- Meat and poultry
- Chicken breast
- Beef liver
- Ground beef
- Other
- Cod liver oil
- Plant-based milks (e.g., soy, almond, oat), vitamin D fortified
- Eggs
- Ready-to-eat cereals, vitamin D fortified
Exposure to sunlight is also another source of 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.
Are There Risks of Taking Vitamin D?
Too much vitamin D can be toxic. Vitamin D toxicity is unlikely to occur from excessive sun exposure or by eating foods high in vitamin D, but it can happen from taking vitamin D supplements inappropriately or in excessive amounts. Talk to your doctor before starting vitamin D supplementation.
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:
- Nausea
- Vomiting
- Loss of appetite
- Dehydration
- Kidney stones
- Muscle weakness
- Neuropsychiatric disturbances
- Pain
- Excessive thirst
- Increased urine production
Severe cases of vitamin D toxicity can lead to:
- Calcification of soft tissues throughout the body (including in coronary vessels and heart valves)
- Renal failure
- Cardiac arrhythmias
- Death
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https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
https://www.uptodate.com/contents/vitamin-d-deficiency-beyond-the-basics?search=vitamin%20d%20deficiency&source=search_result&selectedTitle=2~150&usage_type=default&display_rank=2
https://pubmed.ncbi.nlm.nih.gov/24622804/
https://pubmed.ncbi.nlm.nih.gov/22998754/