Why You Need Vitamin D3 (2024)

Vitamin D3 (cholecalciferol) has a few health benefits, including helping the body absorb calcium. Fish, beef liver, eggs, and cheese naturally contain vitamin D3. It can also be produced in the skin following exposure to ultraviolet (UV) radiation from the sun.

Supplement forms of vitamin D3 are also available and may be used for general health, as well as the treatment or prevention of vitamin D deficiency.

Vitamin D3 is one of two types of vitamin D. It differs from vitamin D2 (ergocalciferol) in both its structure and sources.

The article explains what vitamin D supplements do and the benefits and drawbacks of vitamin D3 specifically. It also lists other essential sources of vitamin D3.

Why You Need Vitamin D

Vitamin D, also called calciferol, is a fat-soluble vitamin (which is broken down by fat and oils in the gut). It is commonly referred to as the "sunshine vitamin" because the D3 type can be naturally produced in the body following exposure to the sun.

Vitamin D has many functions in the body, chief of which include:

• Bone growth
• Bone remodeling
• Regulation of muscle contractions
• Conversion of blood glucose (sugar) into energy

Not getting enough vitamin D can lead to an array of health concerns, including:

• Delayed growth in kids
• Rickets in kids
• Osteomalacia (loss of bone minerals) in adults and adolescents
• Osteoporosis (porous, thinning bones) in adults
  

How Do I Know if I Need More Vitamin D?

If you do not obtain enough vitamin D to meet the body's needs, you are considered to have a vitamin D deficiency. This can be diagnosed through blood testing.

However, the U.S. Preventive Services Task Force does not recommend routine vitamin D screening in adults without symptoms of deficiency.

Not everyone low in vitamin D experiences symptoms. Those who do may notice:

• Muscle and/or bone pain
• Muscle weakness
• History of fractures
• Muscle twitching

If you suspect you could be vitamin D deficient, ask your healthcare provider to test your blood levels or take an at-home test.

Causes for vitamin D deficiency are many, including diseases or conditions that limit fat absorption and the breakdown of vitamin D in the gut. As such, you are at greater risk for vitamin D deficiency if you have:

• Celiac disease
• Crohn's disease
• Cystic fibrosis
• Gastric bypass surgery
• Liver disease
• Malnutrition
• Obesity
• Ulcerative colitis

Older people who are housebound or have dark skin are also more vulnerable to vitamin D deficiency.

Vitamin D deficiency affects almost 50% of the population worldwide. Both vitamin D2 and D3 can be used to treat this, with vitamin D3 generally being the preferred choice.

Vitamin D3 vs. Vitamin D2

Vitamin D2 and vitamin D3 are chemically similar and are both well-absorbed in the gut. Where they differ significantly is in their sources:

• Vitamin D2 is naturally found in mushrooms, including shiitake, portobello, and crimini mushrooms. The vitamin D content increases when these mushrooms are exposed to UV radiation.
• Vitamin D3 is naturally found in animals and animal-derived products like milk. It is also directly synthesized in the skin when it is exposed to ultraviolet B (UVB) radiation.

Aside from the fact that vitamin D3 is likely easier to consume in your day-to-day diet, unless you are a vegetarian or vegan, vitamin D3 has proven superior to vitamin D2 in two other important ways:

• Vitamin D3 has better bioavailability, meaning more of the vitamin enters the bloodstream and can be used by the body
• Vitamin D3 has a better half-life, meaning it stays in circulation for longer

On the downside, vitamin D3 in supplements has historically been synthesized using lanolin derived from sheep's wool. This makes it unsuitable for those who choose to avoid animal-based products.

With that said, some manufacturers have been able to synthesize vitamin D3 from algae and lichen.

Vitamin D3 For Those Without Deficiency

Beyond its use in treating vitamin D deficiency, vitamin D3 may offer health benefits to certain people without such deficiency—in particular, those with high blood pressure or osteoporosis.

Hypertension

Hypertension, more commonly known as high blood pressure, is cardiovascular disease commonly seen in people with vitamin D deficiency.

Recent studies suggest that vitamin D3 may help lower blood pressure in people with hypertension and vitamin D deficiency as well as certain groups of people with hypertension only.

According to a 2019 review of studies in the journal Medicine involving 1,687 people, vitamin D3 was able to significantly reduce systolic ("top number") blood pressure in people over the age of 50 and those with obesity.

This is important because isolated systolic hypertension can increase the risk of stroke, heart disease, and chronic kidney disease over time.

Osteoporosis

Osteoporosis is a frequent consequence of long-term vitamin D deficiency, so common wisdom would suggest that vitamin D supplements may help prevent or slow the progression of this common, aging-related bone disease. There is some evidence to support this claim.

Researchers found that giving Vitamin D3 supplements in addition to calcium supplements can reduce the incidence of hip fractures and non-vertebral fractures in older people.

Sources of Vitamin D3

Whether you are nutritionally deficient or simply want to meet your recommended daily allowance (RDA) of vitamin D, you can obtain ample supplies of vitamin D3 from animal-based foods, dietary supplements, and sun exposure.

Dietary Sources

Food should always be the first source of vitamin D. Here are some of the best dietary sources of vitamin D3 to bolster your intake: