Possibly. Vitamin D deficiency is linked to muscle weakness and bone pain in adults, and many people with low levels feel run down. Direct evidence that low vitamin D causes fatigue, or that supplements lift energy, is limited and mixed, so the best move is to test your level before assuming it is the cause.
What Vitamin D Does in Your Body
Vitamin D is best known for supporting bones. The NIH Office of Dietary Supplements explains that in teens and adults, a true deficiency causes osteomalacia, which brings bone pain and muscle weakness. Weak, achy muscles can easily feel like tiredness, which is one reason low vitamin D gets blamed for low energy.
What Research Says About Vitamin D and Fatigue
The evidence is still developing. A 2023 review of five randomized trials in people with multiple sclerosis found that vitamin D supplementation produced a small reduction in fatigue. The result was fragile, though. It lost statistical significance when one study was removed, the doses varied widely, and most participants started with normal vitamin D levels.
The authors called for larger trials, and the findings apply to people with MS, not necessarily the general public. In plain terms, vitamin D may help some people feel less fatigued, but it is not a proven energy fix.
Who Is at Risk for Low Vitamin D
The NIH says about one in four people in the U.S. have levels that are too low or inadequate. Higher-risk groups include:
- Older adults, whose skin makes less vitamin D from sunlight
- People who rarely get sun exposure, including those who cover up or use sunscreen
- People with darker skin
- People with conditions that limit fat absorption, such as Crohn’s disease, celiac disease, or ulcerative colitis
- People with obesity or a history of gastric bypass surgery
Clouds, smog, and window glass also reduce how much vitamin D your skin makes.
How to Check and Raise Your Vitamin D Level
A blood test for 25-hydroxyvitamin D tells you where you stand. Per the NIH, 20 ng/mL (50 nmol/L) or higher is adequate for most people, below 12 ng/mL (30 nmol/L) is too low, and above 50 ng/mL (125 nmol/L) may cause problems. More is not better.
Few foods contain vitamin D naturally, but fatty fish is among the best sources, and many milks, cereals, and juices are fortified. The recommended daily amount is 600 IU for ages 1 to 70 and 800 IU for ages 71 and older. If you’re tired and wondering about other causes, our guide to why you’re tired all the time even when you sleep enough is a good next read.
Supporting Energy Alongside Healthy Vitamin D
Once your vitamin D is in a healthy range, you can look at other pieces of the energy puzzle. Performance Lab Energy is a caffeine-free formula with magnesium malate, acetyl L-carnitine, R-lipoic acid, CoQ10, PQQ, and BioPerine, ingredients involved in how mitochondria make cellular energy.
Frequently Asked Questions
How Do I Know If My Vitamin D Is Low?
Ask your doctor for a 25-hydroxyvitamin D blood test. Below 12 ng/mL is too low, and 20 ng/mL or higher is adequate for most people.
Can You Get Too Much Vitamin D?
Yes. Levels above 50 ng/mL may cause problems, so check with your doctor before taking high doses.
Is Sunlight Enough to Keep Vitamin D Up?
Not always. Clouds, smog, age, and darker skin reduce production, and window glass blocks it. Food and supplements can fill the gap.
