Vitamin D3, or cholecalciferol, is the biologically active form of vitamin D that is most effective at raising and maintaining blood levels of the nutrient. It is synthesized in the skin from sunlight and is the preferred supplement form due to its superior bioavailability compared to D2.
For individuals who engage in regular physical activity, D3 supports muscle contraction, bone integrity, and immune resilience. It is especially useful in preventing injuries related to calcium deficiency and enhancing recovery after intense exercise.
While general vitamin D benefits apply to both D2 and D3, D3 has been shown to maintain higher levels in the body over time, making it a better choice for supplementation, especially during the winter months or in low-sunlight regions.
Synonyms:
Cholecalciferol
Benefits:
- Supports bone density and calcium absorption
- Enhances muscular function and recovery
- Boosts immunity and reduces infection risk
- May contribute to better strength and coordination
Sources:
Found in animal-based foods such as fatty fish, liver, and egg yolks. Also produced in the skin through sun exposure and available in supplement form.
Observations:
Common in vitamin D supplements or included in multivitamins. Dosages typically range from 1000 IU to 5000 IU. Excessive intake can lead to toxicity symptoms like nausea and calcium imbalance. Synergistic with magnesium and vitamin K2.
Related Areas of Study:
Sports Medicine, Endocrinology, Bone Health, Nutritional Science.