Vitamin D3, also known as cholecalciferol, is a fat-soluble vitamin that plays a crucial role in maintaining overall health. It is naturally produced in the skin upon exposure to sunlight and can also be found in small amounts in certain foods like fatty fish and fortified dairy products. One of the most studied health effects of Vitamin D3 is its ability to support bone health by facilitating calcium absorption in the intestines, which is vital for maintaining strong bones and teeth. Research a

How many studies on Vitamin D3 are available?

NutriVouch references 479 human studies on Vitamin D3, all peer-reviewed and indexed on PubMed.

Is Vitamin D3 effective for Bone Health?

For Bone Health, Vitamin D3 has an effectiveness score of 9/10 — gold-standard treatment with strong clinical evidence. Based on 16 relevant studies.

Is Vitamin D3 effective for Immune Support?

For Immune Support, Vitamin D3 has an effectiveness score of 7/10 — strong evidence supporting clinical use. Based on 16 relevant studies.

Is Vitamin D3 effective for Prenatal Health?

For Prenatal Health, Vitamin D3 has an effectiveness score of 6/10 — moderate evidence — works in some populations. Based on 10 relevant studies.

Is Vitamin D3 effective for Mood Support?

For Mood Support, Vitamin D3 has an effectiveness score of 5/10 — moderate evidence — works in some populations. Based on 22 relevant studies.

Is Vitamin D3 effective for Depression Support?

For Depression Support, Vitamin D3 has an effectiveness score of 5/10 — moderate evidence — works in some populations. Based on 11 relevant studies.

Confidence level

Strong evidence

479 studies

Vitamin D3

Absorption

✦Take with a fat-containing meal to enhance absorption. Avoid taking with large amounts of fiber, which can interfere with its uptake.

Daily Dose

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Common dose: 1,000–2,000 IU daily

RDA: 15 mcg (600 IU)

Upper limit: 100 mcg (4,000 IU)

Best form: D3 (cholecalciferol) preferred over D2

Timing: With a fat-containing meal

Higher doses may be needed for deficiency. Blood testing recommended before megadosing.

Effects

Food Sources

Cod liver oil1360 IU per tablespoon
Salmon (sockeye)447 IU per 100g
Mackerel360 IU per 100g
Sardines (canned in oil)193 IU per 100g
Tuna (canned in water)68 IU per 100g