Vitamin D2 and Vitamin D3: Benefits, Sources, Recommendations

Vitamin D is a major player in keeping the human body healthy. It comes in two main types: vitamin D2 and vitamin D3. Vitamin D2 is found naturally in some foods or added to foods like dairy and cereals. Vitamin D3 is nicknamed the “sunshine vitamin” due to its ability to be made in the presence of sunlight. Its main job is promoting calcium absorption, making it necessary for bone growth and remodeling (when mature bone tissue is removed and new bone tissue is formed).

However, other benefits of vitamin D may include blood pressure regulation, immune system support, weight management, and more. Here are 10 vitamin D benefits to know—including ways to get more of the vitamin in your daily diet.

Adequate vitamin D is crucial for a variety of health functions. Vitamin D comes in two main forms: vitamin D2 and vitamin D3. Vitamin D2 is mostly man-made and is added to various foods, such as fortified dairy products and cereals. When exposed to sunlight, human skin makes vitamin D3, and certain foods like fatty fish also contain the vitamin. Both types of vitamin D have similar health benefits, including the following:

Strengthens Bones

Vitamin D is known for its bone-building and strengthening powers. The nutrient helps the body absorb calcium for improved bone and muscle health. Calcium wouldn’t be able to do its job without vitamin D. The two nutrients together can also help prevent osteoporosis. This condition occurs when a person has weak, brittle bones.

Supports the Immune System

One study published in 2017 found that having frequent bouts of influenza and other respiratory illnesses, living at high latitudes, and the winter season are risk factors for low vitamin D. With that in mind, vitamin D can be beneficial for building immunity.

Researchers analyzed 25 randomized control trials comparing vitamin D supplements to placebos. They found that daily or weekly vitamin D supplementation reduced the risk of acute respiratory infection, particularly in individuals who were deficient in vitamin D.

Helps Strengthen Muscles

Along with its bone-building abilities, vitamin D is also influential in strengthening muscles. The vitamin helps muscle fibers develop and grow, which can help with bone support to increase balance and reduce fall risk.

Promotes Oral Health

Little research exists on vitamin D’s role in oral health. However, one review concluded that because vitamin D helps our body absorb calcium, it may lower the risk of tooth decay, cavities, and gum disease.

May Help Prevent Diabetes

Studies aren’t conclusive, but vitamin D could be beneficial in preventing type 1 and type 2 diabetes. One study published in 2019 found that six months of vitamin D supplementation increased insulin sensitivity in people with diabetes or at high risk of the disease.

May Reduce Irritable Bowel Syndrome Symptoms

Vitamin D may be helpful for individuals with irritable bowel syndrome (IBS), as people with IBS may have vitamin D deficiencies. Some researchers found in one review that, across six studies with data from 572 participants, there was a link between vitamin D supplementation and less severe IBS symptoms.

They suggested the reduction in severity might be due to the anti-inflammatory effects of vitamin D. However, researchers noted the results could not be generalized to all people with IBS. They also said that the relationship between vitamin D supplementation and this change in IBS symptoms is complex and not completely understood.

Can Be Helpful for Depression

The sun can brighten your mood, and so can vitamin D: Researchers found a link between depression and vitamin D deficiency. They acknowledged that more research is needed to define the exact workings of it—such as if low vitamin D levels are a cause or effect of depression.

However, the authors also recommended vitamin D deficiency screenings for individuals with depression and vitamin D deficiency. They noted that these screenings are a cost-effective and simple way to aid in improving outcomes related to depression.

Can Reduce Multiple Sclerosis Risk

Getting enough vitamin D could reduce the likelihood of developing multiple sclerosis (MS). MS is an autoimmune disorder resulting from inflammation-induced nerve damage within the central nervous system (CNS).

Lower vitamin D levels have been linked to an increased risk of multiple sclerosis. However, a higher vitamin D intake may result in lower disease activity, as indicated on an MRI, and a lower relapse risk.

Can Reduce Pregnancy Complications

Consuming enough vitamin D can be beneficial during pregnancy. Vitamin D deficiency has been linked to an increased risk of developing complications such as:

Helps Prevent Rickets in Children

Vitamin D supports bone health, which is especially important for children. If they are lacking in vitamin D intake, they can develop rickets, a disease that softens bones and particularly affects children up to two years old.

Babies should receive 400 international units (IU) of vitamin D daily until they are 12 months old. After that, they need 600 IU.

The daily vitamin D recommendation for adults is as follows:

• Adults aged 19 to 70: 15 micrograms (mcg) or 600 IU
• Pregnant and lactating people: 15mcg or 600 IU
• Adults aged 70+: 20mcg or 800 IU

Approximately 25% of Americans do not have sufficient vitamin D levels. There are a few reasons why a person may be deficient in vitamin D. These reasons range from not getting enough of the vitamin from foods you eat to taking medicines that don’t allow vitamin D conversion or absorption in the body.

Not consuming enough vitamin D can result in:

• Bone density loss
• Bone pain
• Rickets
• Weak bones or muscles

Though vitamin D is good for you, it’s possible to have too much vitamin D. Excessive vitamin D intake is called vitamin D toxicity. Symptoms of this toxicity include:

• Constipation
• Nausea and vomiting
• Poor appetite
• Weakness
• Weight loss

If the level of vitamin D in your body is too high, it can lead to kidney damage. Vitamin D toxicity typically results from using supplements too much, not from sun exposure.

If you find out you are deficient or lacking in vitamin D intake, there are a few key ways you can up your daily dosage, including:

• Eating vitamin D-rich foods: Fatty fish (salmon, tuna, mackerel, and sardines) and mushrooms are natural sources of vitamin D. You can also try fortified milk, juices, yogurts, and breakfast cereals.
• Spending limited time in the sun: The body makes vitamin D3 when exposed to the sun. Remember to wear sunscreen or use sun protection like hats and sunglasses.
• Using supplements: You can always go the supplement route, in the form of vitamin D3, if a healthcare provider thinks it’s necessary. Whatever supplements you use, ensure your vitamin D intake does not exceed the safe upper daily limit of 4,000 IU or 100 mcg.

Dietary supplements may or may not be suitable for you. Supplement effects vary individually, based on type, dosage, frequency of use, and medication interactions. Talk to a healthcare provider or pharmacist before you begin taking supplements.

The sunshine vitamin, vitamin D, is beneficial in many ways. Some of its potential benefits include lowering the risk of MS, helping prevent rickets or diabetes, and strengthening bones and muscles.

You can get vitamin D from foods, sunshine, and supplements. Getting enough vitamin D is important, as too much or too little can have side effects like nausea, bone weakness, and poor appetite.