18 Reasons To Take A Vitamin D Supplement

Why you might not be getting enough vitamin D (and what you can do about it).

Originally Published: 
A man taking a vitamin D supplement.

This article was produced in partnership with d.velop™.

Of the 13 vitamins and minerals deemed essential by the National Institute of Health, vitamin D is the only one that your body produces naturally when you stand in the sun. And that’s not where its uniqueness ends. Vitamin D is a key ingredient in a healthy immune system and an important building block for muscle and bone, but one that over a billion people—that’s billion with a “B”—don’t get enough of.

If that’s not enough to convince you to take a vitamin D supplement on a regular basis, then maybe the 18 reasons below, a mix of reasons you might not be getting enough vitamin D and what adequate vitamin D can do for your—and your kids’—long-term health.

1. It can be hard to spend enough time outside.

Ninety percent of humans’ vitamin D should come from sunlight, but there are many aspects of life, from rainy weather to office work to grocery delivery services, that keep people out of sunlight. These factors depend on where you live, obviously, but it’s not just Seattle-based tech workers, for instance, who aren’t getting enough vitamin D.

2. Sun protection can block vitamin D production.

When sunlight hits the skin, it provides the energy that converts cholesterol in skin cells into vitamin D. That need for direct contact means that sun protection measures demanded by dermatological realities—clothing, sunscreen, shade, etc.—can also limit the amount of vitamin D being outside can provide.

3. Vitamin D helps to increase immune cell production of microbe-fighting proteins.

Antimicrobial peptides, or AMPs as they’re known, serve an important purpose in the immune system, including as a defense against viruses like influenza. Research has shown that vitamin D deficiencies, which rise when people get less sun during the winter, may be the reason that the flu is such a seasonal phenomenon. That would suggest that maintaining adequate vitamin D levels during the colder months could lead to the production of more AMP and decrease the prevalence of the flu.

4. There aren’t a ton of foods naturally rich in vitamin D.

The other ten percent of vitamin D should come from diet. The problem is that there simply aren’t all that many foods that are naturally good sources of vitamin D. So unless you want your diet to contain a lot of fatty fish and egg yolks, it’s a good idea to seek out other sources.

5. Sufficient vitamin D levels are linked to fewer upper respiratory tract infections.

While more research is needed to define the specific mechanism, there is a clear inverse relationship between vitamin D levels and upper respiratory tract infections. One review of 25 different randomized control trials (with more than 11,000 total participants) found that vitamin D supplementation reduced the risk of acute respiratory tract infection.

6. Vitamin D deficiency is associated with increased susceptibility to infection.

Not getting enough vitamin D can cause failures in communication between cells, such as not giving instructions to white blood cells to produce certain proteins that help the body fight illness. Adequate vitamin D facilitates these communications, which ultimately allow immune systems to function properly.

7. Without sufficient vitamin D, bones can become thin, brittle, or misshapen.

Rickets in children and osteomalacia in adults, two very unpleasant bone conditions, happen when vitamin D levels are too low for too long. It’s also necessary for the development of strong bones in children.

8. Vitamin D plays a key role in activating the immune system.

Adequate levels of vitamin D can help to ensure that our immune system has what it needs to protect the body from “invaders” such as bacteria, viruses, and other pathogens. Suboptimal levels of vitamin D may not provide enough of a signal to turn on immune system protection to work effectively and defend against these invaders.

9. Vitamin D can help maintain healthy blood pressure.

Vitamin D helps regulate the renin-angiotensin-aldosterone system, a critical regulator of blood volume and electrolyte balance, both of which contribute to blood pressure.

10. Vitamin D supports both innate immunity…

As its name suggests, innate immunity is present from birth to protect us. It’s also known as “non-specific” because it’s the first line of defense against all of the things that threaten our physical health.

11. …and adaptive immunity.

The other side of the immune system is adaptive or “specific” immunity, the second line of defense against pathogens that we develop over time with a balanced diet and healthy lifestyles.

12. Vitamin D may have some associations with mood.

A Norwegian study of overweight and obese individuals found that taking vitamin D supplements seemed to ameliorate the symptoms of depression, indicating a possible causal relationship. Overall, more research is needed to continue to explore the link between vitamin D and mood.

13. Vitamin D may contribute to factors that influence weight.

Researchers continue to investigate the possible links between vitamin D and weight management as well as how it may impact other factors that can affect weight like mood and poor sleep. Researchers have suggested that people whose weights are considered to be “overweight” or “obese” have their vitamin D levels tested.

14. Pregnant women with adequate vitamin D levels are more likely to give birth to healthy children.

Adverse health outcomes for babies including low birth weight, preeclampsia, neonatal hypocalcemia, and bone fragility have been linked to low vitamin D levels both in utero and during infancy.

15. Good oral health probably depends on vitamin D.

Vitamin D deficiency is associated with a host of oral health disorders. In kids, it can induce tooth mineralization that leads to enamel defects that increase the chances of tooth decay and crumbling. In adults, low vitamin D levels are associated with gum problems like periodontitis.

16. Vitamin D supplementation likely reduces falls.

The evidence suggests that vitamin D plays an important role in building and sustaining muscle mass. Insufficient vitamin D may be related to the development of sarcopenia, which is muscle loss due to aging. Another study found that women who took vitamin D and calcium supplements had dramatically lower chances of falling, which is often caused by muscle weakness.

17. As you get older, your skin’s ability to produce vitamin D decreases.

Aging reduces vitamin D production in skin, which means that taking vitamin D supplements becomes even more important as the years go on.

18. Some necessary medications can negatively affect vitamin D levels.

Laxatives, steroids, cholesterol-lowering drugs, and seizure medications are among the medications that can lead to vitamin D deficiencies. Since simply not taking them is clearly not an option, it’s important to maintain healthy vitamin D levels with supplements while taking anything that could decrease your vitamin D levels. It’s always important to check with your doctor before taking a dietary supplement to make sure all of your medications, and health concerns are considered.

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Clinical studies have shown that ampli-D™ can achieve optimal vitamin D status (30 ng/mL) on average 3X faster, and is 3X more effective, compared to the same mcg amount of conventional vitamin D3. Source: Quesada-Gomez and Bouillon (2018) Osteoporos. Int. 29, 1697-1711.

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