Vitamins D2 and D3: which one to choose and why?

In Canada, the lack of sunlight for many months makes supplementation almost essential to avoid vitamin deficiency. Often called the “sunshine vitamin”, it could play a protective role against certain diseases and supports our immune system; its exact role in the prevention of certain types of cancer is still the subject of active research, according to the National Institute of Public Health of Quebec (INSPQ). However, when choosing your food supplements, a question often arises: should we favor vitamin D2 (ergocalciferol) or vitamin D3 (cholecalciferol)?

Although both forms increase your vitamin levels, their origin and absorption efficiency differ greatly. To ensure effective treatment, it is crucial to understand which of the two molecules remains active the longest in your body.

Understanding the difference between vitamin D2 and vitamin D3

Vitamin D is not a single entity, but a family of essential nutrients. Being a fat-soluble vitamin, it requires the presence of fat to be transported and stored in the body.

The origin of the sources: plant (D2) vs animal (D3)

The main distinction lies in the origin of the resource:

• Vitamin D2: It is mainly of plant origin. It is found naturally in certain mushrooms exposed to UV rays or in enriched products such as plant-based dairy products and juices.

• Vitamin D3: It is the form that our own body synthesizes thanks to the sun. In supplements, it usually comes from lanolin (sheep's wool) or, for vegan options, lichen.

Vitamin D2 is a plant version often derived from yeast or mushrooms, while vitamin D3 is the natural form produced by the skin, known to be much better used by the human body.

Why is vitamin D3 better absorbed by the body?

When it comes to correcting a deficiency, the science clearly leans in favor of D3. Studies show that vitamin D3 raises serum concentrations (blood levels) much more effectively and sustainably than D2.

D3 binds more strongly to the vitamin D blood transport protein (DBP), which slows its elimination and helps maintain high blood levels longer than D2 after taking a dose. This is especially important for older adults or individuals at risk of frailty, as optimal absorption is key to bone health and fall prevention. You will find vitamin D3 supplements from brands like Natural Factors in our selection in store and online.

The essential benefits of adequate supplementation

Why supplement? An optimal dose of vitamin D is essential to promote calcium absorption, strengthen the immune system against winter viruses and could help reduce the risk of certain chronic diseases, although this last point is still the subject of research. In Quebec, supplementation is the only reliable solution to maintain your health when exposure to the sun is insufficient.

The role of the sun and winter deficiencies in Quebec

The Quebec reality: Between October and April, the UV index in Quebec is too low to stimulate the skin's natural vitamin production. Without the help of the sun, the body depletes its reserves, which inevitably leads to a deficiency.

• Public at risk : Elderly people, office workers, and people with dark skin are at a much higher risk of vitamin deficiency.

• Consequence: A drop of serum concentrations weakens the immune response and overall energy starting in the fall.

Bone health, immunity and prevention

The vitamin acts as a regulatory hormone on several vital systems:

1. Bone health: It plays an essential role in the treatment and prevention of osteoporosis, by promoting intestinal absorption of calcium necessary for bone health. It is considered an essential support for pharmacological treatments of osteoporosis, but does not replace them.

2. Immune modulation: It activates natural defenses (T lymphocytes) to better fight common respiratory infections.

3. Prevention and protection: Maintaining good vitamin levels helps with cell protection. Some research suggests that optimal levels may help support cancer prevention and cardiovascular health, though this remains an active area of study.

Which treatment should you choose for your food supplements?

For maximum effectiveness, always favor vitamin D3 (cholecalciferol). It is better recognized by the body than D2 and allows you to reach an optimal blood vitamin level more quickly and maintain it for longer. Whether you are an omnivore or vegan, D3 remains the reference treatment to correct a deficiency.

Choose the D3 for maximum efficiency

The science is clear: according to several studies, vitamin D3 increases serum concentrations more effectively and longer-lasting than D2, particularly when taken occasionally in high doses; the differences reported vary depending on the studies and the parameters measured (from 56% to more than 2 to 3 times depending on whether the blood level or the storage in the tissues is measured).

• Better stability: The D3 molecule is more stable over time, which ensures that the dose of vitamin indicated on your bottle remains active.

• Prolonged retention: Once ingested, D3 circulates in the bloodstream longer, providing continued protection for your bone health and immune system.

• Recommended use: This is the form favored by health professionals for the treatment of winter deficiencies in Quebec.

Options for vegans (D3 from lichen)

For a long time, vegans had to make do with vitamin D2 (from mushrooms), which was less effective. This is no longer the case today.

• The lichen revolution: Vitamin D3 is now extracted from lichen (a symbiosis of fungus and algae).

• Same efficiency: This plant D3 has exactly the same molecular structure as animal D3. It therefore offers the same vitamin and benefits without any product of animal origin.

• Suitable for everyone: This is a great prevention option for those who follow a strict diet while refusing to compromise on the quality of their vitamin intake.

FAQ: Your questions about vitamin D

What is the main difference between vitamin D2 and vitamin D3?

Vitamin D2 generally comes from plant sources (mushrooms, yeast), while vitamin D3 is the form produced naturally by the skin during exposure to the sun or from animal sources (lanolin, fatty fish). D3 is known to raise blood levels more effectively.

Can you take vitamin D2 if you are vegan?

Yes, D2 is traditionally the vegan option. However, there are now dietary supplements of vitamin D3 extracted from lichen, offering a plant-based alternative that is just as powerful as animal D3.

Can vitamin D help prevent cancer?

Several studies suggest that optimal vitamin D levels could play a role in reducing the risk of certain types of cancer (notably colorectal and breast) by regulating cell growth. Medical monitoring is necessary for any specific treatment.

At what time of day should you take your supplement?

As it is a fat-soluble vitamin (which dissolves in fats), it is strongly recommended to take it during a meal containing good fats (avocado, olive oil, nuts) to ensure optimal absorption.

Conclusion: Optimize your vitamin levels throughout the year

To effectively counteract the lack of sun and protect your health, vitamin D3 is the logical choice. More efficient than D2, it provides better prevention against winter ailments and sustainably supports your bone mineral density.

It is important to remember that each individual has unique needs. Depending on your age, diet or daily exposure, the ideal vitamin dose may vary. To obtain personalized treatment and choose among the best food supplements on the market, do not hesitate to consult our expert advisors. 

References

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6. Comparison of the Effect of Daily Vitamin D2 and Vitamin D3 Supplementation on Serum 25-Hydroxyvitamin D Concentration. Advances in Nutrition, PMC (NIH). 2023. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10831883/
7. The use of calcium and vitamin D in the management of osteoporosis. PMC (NIH). https://pmc.ncbi.nlm.nih.gov/articles/PMC2621390/
8. Calcium and Vitamin D Supplementation on Bone Health: Current Evidence and Recommendations. ScienceDirect. https://www.sciencedirect.com/science/article/pii/S1873959814000891