Differences Between Vitamin D2 and Vitamin D3

Vitamin D2 and vitamin D3 are two different forms of the same nutrient that can be used by the body. Learn more about them.
Differences Between Vitamin D2 and Vitamin D3
Saúl Sánchez

Written and verified by el nutricionista Saúl Sánchez.

Last update: 19 March, 2023

Vitamin D is a nutrient that can be found in different configurations in the body or in nature. It’s essential to achieve a correct state of health, as a vitamin D deficit is related to alterations at the inflammatory level and a greater risk of developing complex diseases. Specifically, we’re going to show you the difference between two of its most common forms, vitamin D2 and D3.

The first thing that we must make clear is that at least 50% of the population fails to meet the daily requirements of the nutrient, which is why it presents an inadequate level in the body. Preventing this situation requires optimizing the diet and increasing exposure to sunlight. Likewise, the inclusion of supplements in the diet may become necessary.

Vitamin D2

Vitamin D2 is a nutrient that comes from mainly plant foods. The most typical examples are mushrooms. These have a relatively low concentration of the substance, so it’s difficult to reach the recommended daily doses through these vegetables. Of course, once vitamin D2 is ingested, it quickly transforms into type D in the body.

From a technical point of view, this nutrient is known as ergocalciferol. It has a water-soluble character and can also occur in certain yeasts. Vitamin supplements often contain this active form. They’ve been shown to be capable of preventing the development of certain diseases or reducing their severity, especially when exposure to the sun is insufficient. This is stated by a study published in the Journal of Infection and Public Health.

Vitamin D3

A woman standing by a pool with a picture of the sun drawn on her back with sunscreen.
One of the benefits of sun exposure is the endogenous synthesis of vitamin D, but using sunscreen on a regular basis is also important to avoid skin diseases.

Vitamin D3 is what the body synthesizes from radiation. It’s considered a higher quality nutrient than the version present in food. It can be stored in the body’s adipose tissue, so it’s important to sunbathe during the summer to avoid vitamin deficiencies in the winter.

It’s important to take into account that maintaining low levels of vitamin D in the body is a risk factor for the appearance of diseases, such as cardiovascular diseases. According to research published in In Vivo, this marker in the blood can be used as a predictor. The need to revise (increase) the optimal doses of the vitamin in the body is even currently being debated.

Importantly, vitamin D can’t be synthesized endogenously under all circumstances. For example, sunscreens often block radiation that stimulates the production of the substance, known as cholecalciferol. In this case, the levels of it in the body could be compromised, which would be negative for health.

The production rate isn’t identical in the different seasons of the year either. The position of the Earth with respect to the Sun has a decisive influence. Therefore, summer is the best time to ensure optimal synthesis of the substance. Likewise, it should be noted that vitamin D3 can also be administered through supplements, being much more effective in increasing the concentration in the blood than vitamin D2.

Vitamin D toxicity

It’s true that an excessively high dose of vitamin D2 or D3 could be toxic to the body. However, this situation is difficult to achieve. The concentration of the nutrient in food is low enough to prevent this scenario from occurring, even in the context of a poorly varied diet. Through exposure to sunlight, it’s also impossible to experience an overdose.

Now, it’s true that the indiscriminate consumption of vitamin D supplements, in any of their forms, could cause an excess of the nutrient in the serum. In this case, the most typical symptoms will be confusion, abdominal pain, vomiting, and a higher concentration of calcium in the blood. This is confirmed by a study published in the journal Frontiers in Endocrinology.

Even so, we’re talking about a very rare situation. The most common with regard to vitamin D is to suffer a deficit, not an excess. In fact, this is considered a serious public health problem, responsible for a large number of deaths a year around the world. It’s important to remedy it through good dietary and lifestyle habits.

Vitamin D and its relationship with cancer

It’s important to note that vitamin D is a nutrient that is closely related to cancer in any of its forms. Maintaining adequate levels of the substance in the body or even supplementation could help increase survival from the disease. Chemo results can even be improved, according to research published in The Journal of Steroid Biochemistry and Molecular Biology.

In fact, it’s possible to find some trials that show that patients with tumor diseases who are frequently exposed to sunlight have a greater chance of surviving. In this sense, the systematic inclusion of a vitamin D supplement as a prevention and aid method to prevent tumor progression is evaluated.

Even so, there are certain disagreements in this regard. The intervention of a dietary nature in cancer patients still requires more research. The indications that have been given to date are scarce and not very consistent. At present, more attention is being paid to this field, given the results of published studies.

Not only is it important to maximize the levels of vitamin D in the body, but many other essential elements can mark the future of this disease. For example, vitamin C can exert an important antioxidant effect that neutralizes the formation of free radicals. Also, selenium.

Other foods with vitamin D

We’ve discussed that vitamin D2 is found primarily in foods of plant origin, such as fungi and yeasts. However, there are certain edibles of animal origin that contain this nutrient, although in a different form. They’re mainly eggs, oily fish, and dairy products.

All of them are considered healthy and are recommended in the context of a balanced and varied diet. At this same time, they can provide a significant amount of proteins of high biological value. These elements help keep the muscle active and functional, avoiding chronic diseases related to lean mass, such as sarcopenia.

It should be noted that one of the great allies of vitamin D to improve disease prevention is physical exercise. It’s important to stay active, prioritizing strength work above all. In this regard, a state of balance in the internal environment, beneficial for health in the medium term, will be guaranteed.

As stated by research published in the journal BMJ, losses in grip strength are associated with an increased risk of death from any cause. Also, the catabolism of lean mass is considered a bad marker when it comes to chronic and complex diseases. There’s no reason to believe that aging will cause you to experience a reduction in muscle capacity, as this doesn’t have to be the case if you exercise.

Along these lines, it’s important to remember that a deficiency of vitamin D in the body can be one of the causes of reduced muscle strength, as current evidence suggests. For this reason, it will always be necessary to guarantee a varied diet and exposure to sunlight. You can even consider nutritional supplementation. However, in this regard, it’s best to first with a nutritionist.

How to detect a vitamin D deficiency?

A woman standing in a dark room during the day, peeking through the blinds to look outdoors.
Lack of exposure to sunlight, something characteristic of certain regions or people, could lead to a vitamin D deficiency.

We’ve mentioned that a vitamin D deficiency is related to a worse state of health. However, we must be attentive to possible symptoms to prevent this situation early and apply an efficient remedy. In the first place, a nutrient deficiency can be suspected when exposure to sunlight during the year isn’t adequate, either due to a person’s lifestyle or due to weather conditions.

In many countries, especially those located to the north, there often aren’t enough hours of light to achieve optimal production of the nutrient inside the body. Here, the best option would be to opt for supplementation in a systematic way, although vitamin D that’s endogenously synthesized usually has higher quality.

At the same time, symptoms such as weakness, tiredness, dizziness, or lack of strength may indicate that the levels of the nutrient in the body aren’t adequate. According to a study published in the journal Reviews in Endocrine & Metabolic Disorders, such a situation could increase the risk of developing metabolic problems, as physical activity will also be affected.

Vitamin D2 and vitamin D3: Two forms of the same nutrient

As you’ve seen, vitamin D2 and vitamin D3 differ in their chemical structure, their origin, and their effects on the levels of vitamin D as such in the blood. However, it’s crucial to ensure the intake or synthesis of this element in order to achieve good health in the medium term.

Remember that not only diet matters when it comes to preventing diseases. Promoting other good lifestyle habits, such as regular physical exercise, will also make a difference. Exposure to sunlight is key. However, a principle of progression must be followed to avoid burns that could put the skin at risk.



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