Does vitamin D give you energy?

A man standing outside with his eyes closed, soaking up some sunlight.
(Image credit: Getty Images)

Most of us know that vitamin D builds strong, healthy bones and teeth, and some of us know that it has other health benefits, from protecting against serious diseases to supporting our immune system. But does vitamin D give you energy too? 

To an extent, vitamin D does play a role in reducing fatigue and boosting energy levels. This is because it aids the function of the mitochondria within the body’s cells, which is responsible for creating energy. 

Here, we’ve taken a deeper dive into the research around vitamin D and energy, and spoken to the experts to explain how it all works.

What is vitamin D?

Vitamin D (sometimes referred to as calciferol) is a vitamin that we obtain from exposure to sunlight, certain foods and supplements. It enables the body to absorb calcium and phosphorus from food passing through the gut, which helps to grow strong, healthy bones and teeth. If we don’t get enough vitamin D, our bones can become brittle, weak and misshapen.

There are several other health benefits of vitamin D:

  • It supports a strong and healthy immune system by fighting off bacteria and viruses 
  • It regulates heart function and reduces blood pressure 
  • It may reduce the risk of certain diseases, such as cancer, type 2 diabetes and multiple sclerosis

There is also evidence that low vitamin D levels may contribute to low mood, according to a review in the Depression and Anxiety journal. However, we need more research to establish the exact link.

Does vitamin D affect your energy levels?

The evidence suggests that it does. According to the Cleveland Clinic, some of the top symptoms of vitamin D deficiency in adults are fatigue, muscle weakness and low mood, all of which can make us feel down and exhausted. 

A double-blind trial in the Medicine journal compared the results of two groups who experienced fatigue and vitamin D deficiency. One group was given vitamin D supplements, while the other was given a placebo. Researchers found that the group given vitamin D experienced significant improvements in energy levels in just four weeks.

Dietitian Rahaf Al Bochi, a spokesperson for the Academy of Nutrition and Dietetics, also tells Live Science vitamin D deficiency is associated with low energy levels. “Vitamin D has been shown in research to aid the function of the mitochondria within the body’s cells, which is responsible for creating energy,” she says.

Rahaf Al Bochi, RDN
Rahaf Al Bochi, RDN, LDN

Al Bochi is a registered nutritionist and spokesperson for the Academy of Nutrition and Dietetics. She practices through an intuitive eating approach and specializes in the Mediterranean eating pattern.  She is a member of the Academy's Nutrition Entrepreneurs dietetic practice group and a graduate of Ryerson University.

This research was published in Endocrine Abstracts and found that vitamin D supplementation in deficient adults improved muscle function by turbo-charging the mitochondria — the batteries our cells need to function. Every patient in the study reported an improvement in energy levels after taking a fixed dose of vitamin D for 10 to 12 weeks.

Where do you get vitamin D?

“Your body can make vitamin D when exposed to sunlight,” says Al Bochi. In fact, most people get their vitamin D this way in the summer, according to the National Institutes of Health, and it doesn’t take much exposure for your body to start producing it.

However, the Skin Foundation warns that even short, limited exposure is more than enough time to cause DNA damage that causes genetic mutations, increasing the risk of skin cancer throughout your lifetime.  

Older people and people with brown or black skin are less likely to benefit from sun exposure because their skin is less able to make vitamin D from sunlight. And only some people want to expose their arms, legs and face in public. 

Side view portrait of a happy woman breathing deep fresh air at sunset in a house balcony

(Image credit: Getty Images)

Although it’s challenging to get all the vitamin D you need from food alone, certain foods are naturally rich in vitamin D. These include: fortified foods and drinks such as milk or breakfast cereals, oily fish such as salmon, mackerel, sardines, tuna and fish liver oils, egg yolks, cheese and some mushrooms.

“A vitamin D supplement may be needed, especially during the winter months when sunlight exposure is limited,” adds Al Bochi. 

The NIH recommends getting 400 international units (IU) a day for children up to one year, 600 IU for people aged one to 70, and 800 IU for people over 70.

If you’re unsure how much vitamin D you should take, speak to your doctor or a registered dietician for advice. Too much vitamin D can cause calcium to build up in the blood, resulting in nausea, vomiting and weakness. It can even lead to a potentially serious condition called hypervitaminosis D.

This article is for informational purposes only and is not meant to offer medical advice.

Joanne Lewsley

Joanne Lewsley is a UK-based freelance writer and editor, covering health and lifestyle news and features. She mainly creates evidence-based health and parenting content and has worked with a number of global sites, including BabyCentre UK, Medical News Today, Fit & Well, Top Ten Reviews, and Yahoo!