Is it better to get vitamin D or vitamin D3? Understanding the Differences

October 18, 2025 •

3 min read

Recent research and meta-analyses suggest that vitamin D3 is significantly more effective at increasing and maintaining blood vitamin D levels than vitamin D2, making the answer to 'is it better to get vitamin D or vitamin D3?' a compelling point for nutrition-focused individuals. This distinction is crucial for those seeking the optimal form of this essential nutrient for bone health and immune function.

Quick Summary

Vitamin D is an umbrella term for two forms: D2 (ergocalciferol) and D3 (cholecalciferol). Studies show D3 is more effective and potent at raising blood levels for a longer duration. While D2 is plant-based, D3 is synthesized from sun exposure and animal sources, though vegan D3 is now available. Supplement choice depends on dietary needs and efficacy preferences.

Key Points

D3 is more effective than D2: Studies consistently show that vitamin D3 (cholecalciferol) is more potent at raising and sustaining blood vitamin D levels than D2 (ergocalciferol).
Sources differ for D2 and D3: D3 is produced in the skin from sun exposure and found in animal products, while D2 is plant-based, found in mushrooms and fortified foods.
Vegans can choose D3: Plant-based D3, derived from lichen, is available for vegans seeking the more effective form of the vitamin.
D3 offers better supplement stability: Evidence suggests D3 may be more stable and less prone to degradation than D2 in supplement form.
Take supplements with fat: As a fat-soluble vitamin, D3 (and D2) is best absorbed when consumed with a meal containing some fat.
Consult a healthcare provider: Individual needs for vitamin D vary based on sun exposure, diet, and health status, so professional advice is crucial for determining the right dose.

What Exactly Are Vitamin D, D2, and D3?

Vitamin D is a fat-soluble vitamin essential for regulating calcium and phosphate in the body, which is critical for healthy bones, teeth, and muscle function. The term 'Vitamin D' refers to a group of related nutrients, primarily vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). The primary distinction lies in their source and biological potency, which influences how our bodies process and utilize them.

The Source and Origin Story

Vitamin D3 (Cholecalciferol): This is the form our bodies naturally produce when skin is exposed to sunlight's ultraviolet B (UVB) radiation. It is also found in animal-sourced foods like fatty fish (salmon, trout), fish liver oil, and egg yolks. For vegans, D3 derived from lichen is now a widely available option.
Vitamin D2 (Ergocalciferol): Found in plants, this form is produced when UV light interacts with ergosterol in fungi such as yeast and mushrooms. It is often used to fortify foods, including some plant-based milks and cereals.

Metabolism and Effectiveness

Both D2 and D3 are absorbed effectively and undergo a two-step activation process in the liver and kidneys. However, multiple studies indicate that D3 is more potent and efficient than D2 at increasing and sustaining blood levels of 25-hydroxyvitamin D, the form measured to assess vitamin D status. D3's ability to maintain higher levels for longer makes it more favorable for correcting deficiencies.

Supplement Stability

Some research suggests D2 supplements may be more sensitive to temperature and humidity, potentially degrading faster than D3 over time. For supplementation, D3 is often preferred due to its higher efficacy and stability. Plant-based D3 from lichen is an effective option for vegans.

Comparison of Vitamin D2 and Vitamin D3


Feature	Vitamin D2 (Ergocalciferol)	Vitamin D3 (Cholecalciferol)
Primary Source	Plant-based (fungi, mushrooms, fortified foods).	Animal-based (sunlight exposure, fatty fish, egg yolks). Vegan version from lichen.
Effectiveness	Less potent at raising and maintaining blood levels.	More potent and effective for improving vitamin D status.
Supplement Stability	Potentially more sensitive to environmental factors and less stable.	Generally considered more stable, with less risk of degradation.
Dietary Suitability	Natural choice for vegans and vegetarians from plant sources.	Primary choice for omnivores. Vegan D3 derived from lichen available for vegans.

Choosing the Right Vitamin D for Your Needs

The choice between D2 and D3 often comes down to a few key factors, with D3 generally offering superior efficacy.

For Omnivores and Most People

For individuals who do not follow a plant-exclusive diet, vitamin D3 is the recommended choice for supplementation. It is widely available and more effective at raising and sustaining blood vitamin D levels. Your body also produces D3 from sun exposure, making it the most physiological form.

For Vegans and Vegetarians

While D2 from fortified foods is an option for plant-based diets, vegan-friendly D3 supplements from lichen are now available and offer the superior effectiveness of D3. Always check the product label to ensure the D3 is lichen-sourced.

The Importance of Overall Context

Proper supplementation involves more than just selecting D2 or D3:

Dosage: Consult a healthcare professional for the correct dose based on your blood levels, as excessive intake can lead to toxicity.
Absorption: Take vitamin D with a meal containing some fat for better absorption.
Lifestyle Factors: Sun exposure, BMI, and other health conditions influence your needs.

Conclusion: The Best Choice for a Nutrition Diet

When debating is it better to get vitamin D or vitamin D3, the evidence supports D3 for supplementation due to its superior effectiveness in raising and maintaining blood vitamin D levels. For most people, and especially those correcting a deficiency, D3 is recommended. Vegan D3 from lichen offers a potent alternative for those on plant-based diets. Always consult a healthcare provider to determine your individual needs and dosage.

For more information, refer to the National Institutes of Health (NIH) Office of Dietary Supplements website.

Frequently Asked Questions

The main difference is that Vitamin D is the general term for the nutrient, which includes several forms. Vitamin D3 (cholecalciferol) is one specific, more potent form of Vitamin D, while D2 (ergocalciferol) is another.

Both forms are absorbed effectively, but research indicates that vitamin D3 is utilized more efficiently and maintains higher blood levels for longer compared to vitamin D2.

While vitamin D2 is plant-based, vegan-friendly D3 derived from lichen is now available. Given D3's superior effectiveness, plant-based D3 is the recommended choice for vegans aiming for maximum potency.

Sunlight is the primary source of vitamin D3, but factors like geographic location, skin tone, and use of sunscreen can limit production. Most people, especially during winter months, cannot rely solely on sun exposure and may need supplements.

Food sources of vitamin D3 include fatty fish such as salmon and trout, fish liver oils, egg yolks, and fortified dairy products. Vegans can find D3 in fortified foods or lichen-based supplements.

Yes, it is possible to have too much vitamin D from excessive oral supplementation, but not from sun exposure. This can lead to vitamin D toxicity and hypercalcemia.

Vitamin D deficiency is linked to several health issues, including bone disorders like osteoporosis and rickets, and may affect immune function, muscle strength, and mood.