The Benefits of Vitamin D from Head to Toe, Says Science

Vitamin D can lead to sharper eyesight, better memory, slower aging...and so much more.

Pouring capsules into handSCIENCE PHOTO LIBRARY/Getty Images

Is it the magic vitamin? Well, it might be close. Research in recent years has shown that vitamin D may be one of the most powerful supplements to boost your total wellness and even help promote longevity.

For years, vitamin D was touted as an ace for stronger bones, shinier hair, and as a potential mood-booster. But you might not be aware of the many benefits vitamin D can provide for your whole system.

Dietitians Just Shared 6 Tips to Help Your Gut Absorb Vitamin D

Brain

brain benefits of vitamin DSensorSpot/Getty Images

When taken with fish oil, vitamin D is a powerful mood booster, according to a study published in the FASEB journal. The aptly named “sunshine vitamin” improves mood and lowers depression by aiding the conversion of the essential amino acid tryptophan into serotonin—a brain chemical that regulates mood.

But that’s not all! Vitamin D improved memory and cognitive functions in older women, according to a separate study published in Journals of Gerontology A. Meanwhile, previous research has found it may also have some protective effects against Alzheimer’s disease—read 8 Supplements and Vitamins for Memory—What Works and What Doesn’t.


Eyes

Adult woman green eyes with wrinkles closeupVolanthevist/Getty Images

Laugh lines aside, your eyes themselves undergo signs of aging that can impair your vision. A daily dose of vitamin D reduced some of the effects of aging on eyes, reduced inflammation, and improved vision in mice, according to a study published in Neurobiology of Aging.

A second study found that it may also help prevent macular degeneration, a common eye disease that can lead to blindness if it goes untreated.


Ears

Earb-d-s/Getty Images

What causes vertigo, that disorienting sensation of dizziness and spinning? Vertigo may feel like your head is spinning, but the problem often stems from the structures in your inner ear that are responsible for balance.

However, taking vitamin D and calcium twice a day may reduce vertigo and lower your chances of getting vertigo again, according to a study published in Neurology.


Teeth

teeth benefits of vitamin DTetra Images/Getty Images

Want stronger, whiter teeth and fewer cavities? Taking a daily vitamin D supplement may help, according to a meta-analysis published in Nutrients. Researchers analyzed dozens of controlled studies with thousands of participants in several countries to find that that vitamin D was associated with a 50-percent reduction in the incidence of tooth decay.

10 Things Dentists Do to Prevent Tooth Decay


Gums

Comprehensive dental examinationBatke/Getty Images

The same vitamin D supplement that strengthens your teeth can also help protect your gums from bacterial infections that lead to problems like gingivitis and periodontitis, according to the Nutrients study.

Periodontitis, a potentially serious infection of the gum tissue, affects up to 50 percent of people in the U.S. It’s a major cause of tooth loss and can also contribute to heart disease. Protect yourself by knowing the early signs of gum disease.


Heart

Senior African descent woman clutches chest in painfstop123/Getty Images

One of vitamin D’s most powerful roles is in the cardiovascular system, where there are 200 genes regulated by vitamin D. How does it work? Vitamin D may help stop cholesterol from clogging arteries, regulate blood pressure, and improve the function of cells in the heart.

Even better, it may also be able to help heal existing heart damage, according to research published in the International Journal of Nanomedicine.

23 Vitamin D Benefits That Can Save Your Life


Lungs

Close up of unrecognizable woman doing breathing exercises at the parkHispanolistic/Getty Images

Asthma, chronic obstructive pulmonary disease (COPD), emphysema and chronic bronchitis affect about 15 percent of Americans, according to the most current data from the CDC. While it’s not a cure, vitamin D can reduce the number of lung disease flareups by 40 percent, a study published in The Lancet concluded.

The same may be true for asthma, according to a separate study published in Cochrane Review. Researchers found that people who took a daily dose of vitamin D in addition to their asthma medication reduced the number of severe asthma attacks they experienced.


Gut

gutLaurence Monneret/Getty Images

People with metabolic syndrome— increased blood pressure, high blood sugar, excess body fat around the waist, and abnormal cholesterol or triglyceride levels—are at a high risk for heart disease, stroke and type 2 diabetes.

Exercise and a healthy diet are important practices to avoid or heal the syndrome, but research has suggested vitamin D may also help. In a study published in Frontiers in Physiology, vitamin D improved signs of metabolic syndrome by boosting healthy gut bacteria in mice.

Types of Probiotics and How to Pick the Right One for Your Needs, according to Gut Health Research


Liver

African woman suffering from liver pain, croppedProstock-Studio/Getty Images

Higher vitamin D levels are linked with lower levels of cancer in general, and less liver cancer specifically, according to a BMJ study. Researchers took samples from over 33,000 adult participants and found that higher levels of the nutrient were associated with a 20-percent reduction in cancer and a 30 to 50 percent reduction in liver cancer. Read 9 Silent Signs of Liver Cancer You Shouldn’t Ignore


Reproductive system

Hands of newborn baby and motherKohei Hara/Getty Images

Both men and women show reproductive and fertility benefits from vitamin D. Female participants who had a healthy vitamin D level early in pregnancy were more likely to have a baby with a healthy weight and head size in a study published in the Journal of Clinical Endocrinology & Metabolism.

Similarly, men with higher vitamin D levels had a better fertility potential, particularly through better sperm motility, say researchers in a separate study, published in World Journal of Men’s Health.

15 Everyday Things That May Be Harming Your Fertility


Bones

X-ray of knee - osteoarthritis and rheumatoid arthritisPeter Dazeley/Getty Images

Think calcium is the best nutrient for bones? Think again. The positive effects of vitamin D on bone health are some of the most documented benefits of the nutrient. Vitamin D is essential to building and maintaining strong bones, while inadequate vitamin D can lead to osteoporosis, a brittle bone disease, according to the Mayo Clinic.

Does Yoga Strengthen Your Bones? An Orthopedic Surgeon’s Answer Might Surprise You


Knees

Black woman massaging her painful knee, close upProstock-Studio/Getty Images

Your knees are one of the most-used joints in your body and often one of the first places to experience joint pain as you get older. Research has suggested the most common causes of joint pain are osteoarthritis from joint overuse or injury, and rheumatoid arthritis—an autoimmune disease that attacks joints.

Vitamin D can help protect against both types of arthritis. People who maintained healthy vitamin D levels were less likely to get rheumatoid arthritis, according to a study published in Journal of Autoimmunity. Similarly, people with low vitamin D levels reported more symptoms of osteoarthritis, like knee pain and difficulty walking, according to research by the American College of Rheumatology.

Read Everything You Need to Know About Supplements for Joint Pain


Feet

Sore feet cannot walk Use both hands to massage the feet.chanakon laorob/Getty Images

Stress fractures—microfractures that often occur in small bones due to overuse—are fairly common injuries, particularly in people who participate in high impact activities, like running or sports, or people who are significantly overweight. According to a study published in The Journal of Foot and Ankle Surgery, vitamin D may reduce stress fractures by helping improve bone density.

Stay connected on staying healthy by signing up for The Healthy @Reader’s Digest daily newsletter. Follow us on Facebook and Instagram, and keep reading:

Popular Videos

Sources
  • Harvard School of Public Health: "Vitamin D"
  • FASEB Journal: "Vitamin D and the omega-3 fatty acids control serotonin synthesis and action, part 2: relevance for ADHD, bipolar disorder, schizophrenia, and impulsive behavior"
  • Journals of Gerontology A: "Three Doses of Vitamin D and Cognitive Outcomes in Older Women: A Double-Blind Randomized Controlled Trial"
  • Neurobiology of Aging: "Vitamin D rejuvenates aging eyes by reducing inflammation, clearing amyloid beta and improving visual function"
  • JAMA Ophthalmology: "Association Between Vitamin D Status and Age-Related Macular Degeneration by Genetic Risk."
  • Neurology: "Prevention of Benign Paroxysmal Positional Vertigo with Vit D Supplementation: A Randomized Trial."
  • Nutrients: "Vitamin D Deficiency and Oral Health: A Comprehensive Review"
  • Infection and Immunity: "Vitamin D-Mediated Induction of Innate Immunity in Gingival Epithelial Cells."
  • International Journal of Nanomedicine: "Nanomedical studies of the restoration of nitric oxide/peroxynitrite balance in dysfunctional endothelium by 1,25-dihydroxy vitamin D 3 - clinical implications for cardiovascular diseases"
  • CDC: "Lung Obstruction Among Adults Aged 40–79: United States, 2007–2012"
  • The Lancet Respiratory Medicine: "Vitamin D3 supplementation in patients with chronic obstructive pulmonary disease (ViDiCO): a multicentre, double-blind, randomised controlled trial"
  • Cochrane Library: "Vitamin D for the management of asthma"
  • Frontiers in Physiology: "Vitamin D Signaling through Induction of Paneth Cell Defensins Maintains Gut Microbiota and Improves Metabolic Disorders and Hepatic Steatosis in Animal Models."
  • BMJ: "Plasma 25-hydroxyvitamin D concentration and subsequent risk of total and site specific cancers in Japanese population: large case-cohort study within Japan Public Health Center-based Prospective Study cohort."
  • Journal of Clinical Endocrinology & Metabolism: "Maternal Serum 25-Hydroxyvitamin D and Measures of Newborn and Placental Weight in a U.S. Multicenter Cohort Study."
  • World Journal of Men's Health: "Vitamin D and Male Fertility: An Updated Review"
  • Mayo Clinic: "Vitamin D is essential to strong bones. Inadequate vitamin D can lead to osteoporosis, a brittle bone disease."
  • Journal of Autoimmunity: "Decreased sensitivity to 1,25-dihydroxyvitamin D3 in T cells from the rheumatoid joint."
  • American College of Rheumatology: "Low Vitamin D Levels May Worsen Osteoarthritis of the Knee"
  • The Journal of Foot and Ankle Surgery: "Association of Vitamin D With Stress Fractures: A Retrospective Cohort Study".

Charlotte Hilton Andersen
Charlotte Hilton Andersen, MS, is an award-winning journalist, author, and ghostwriter who for nearly two decades has covered health, fitness, parenting, relationships, and other wellness and lifestyle topics for major outlets, including Reader’s Digest, O, The Oprah Magazine, Women’s Health, and many more. Charlotte has made appearances with television news outlets such as CBS, NBC, and FOX. She is a certified group fitness instructor in Denver, where she lives with her husband and their five children.