Yes, low vitamin D can definitely cause fatigue, with studies linking deficiency to persistent tiredness, low energy, and exhaustion, often improving with supplementation. It impacts energy production, immune function, and muscle health, leading to feeling worn out even after rest, making it a common but often overlooked symptom, alongside muscle weakness, bone pain, and mood changes.
Some of the effects of vitamin D deficiency include:
Vitamin D is known for its importance for bone health. But it also plays a role in inflammation, immune health, mental health, and energy production. Low vitamin D levels have been linked with fatigue. Adding a vitamin D supplement to your diet may help improve your energy levels after a month.
High doses of Vitamin D supplements may contribute to headaches if they cause blood calcium levels to rise too much. This typically occurs with prolonged high-dose Vitamin D supplementation rather than standard daily dosing. Symptoms may also appear alongside nausea, increased thirst or general fatigue.
Vitamin D deficiency was more prevalent in acne patients than in HCs (pooled OR = 2.97, 95% CI = 1.68-5.23, I2 = 72%). Also, vitamin D levels were negatively correlated with acne severity. Conclusion: This meta-analysis demonstrated the significantly low vitamin D levels in acne patients.
Here are 10 unexpected signs of a vitamin D deficiency that may surprise you.
Estrogen Imbalance: Vitamin D deficiency can lead to lower estrogen levels, causing depression, hot flashes, mood swings, and more. Parathyroid Hormone Imbalance: Vitamin D deficiency limits the body's ability to regulate calcium levels controlled by the parathyroid gland.
Individuals with deficient or insufficient circulating vitamin D concentrations (i.e., <30 ng/mL) are more likely to take longer to fall asleep (i.e., longer sleep latency and later sleep timing) and/or exhibit shorter sleep duration (11–16).
B vitamins and headaches
Vitamin B12 deficiency can lead to anemia (low red blood cell count). And this can indirectly cause headaches. There's some evidence that vitamin B1 and vitamin B12 deficiencies may be linked to migraines. Severe vitamin B3 and vitamin B5 deficiencies can cause headaches.
Certain groups of people are more likely than others to have inadequate vitamin D status. These include breastfed infants, older adults, people with limited sun exposure, people with dark skin, people with conditions that limit fat absorption, and people with obesity or those who have undergone gastric bypass surgery.
[9,10] Low vitamin D leads to bone abnormalities (e.g., osteomalacia, osteopenia, and osteoporosis) and worsens muscle strength. [11] In otherwise healthy individuals, fatigue can be a manifestation of low vitamin D levels and its impact on reduced maximum functioning of skeletal muscles via vitamin D receptors.
Chronic fatigue is one of the most common and overlooked signs of vitamin deficiency. If you find yourself constantly tired, even after a good night's sleep, a lack of vitamin B12 might be to blame. This essential vitamin is responsible for energy production, red blood cell formation, and proper neurological function.
The Role of Vitamin D
Furthermore, some research suggests that vitamin D deficiency may be linked to an increased risk and severity of osteoarthritis, a common cause of joint pain. Ensuring adequate vitamin D levels through sunlight exposure, diet, or supplementation can be a crucial step in managing joint discomfort.
Vitamin and mineral deficiencies, including B2, B3, B5, B6, B9, B12, C, D, iron, and magnesium, are among the most common causes of unexplained fatigue. Vitamin D deficiencies affect over 50% of the global population, and approximately 12.5% have iron deficiency anemia.
Taking an over-the-counter vitamin D supplement can help raise your levels and improve deficiency symptoms within six weeks to four months, depending on how severe your deficiency is. You may begin to feel consistently more energetic and in a better mood when your use of vitamin D supplements starts to work.
You can become deficient in vitamin D for different reasons:
Symptoms when vitamin D is low
Fatigue. Not sleeping well. Bone pain or achiness. Depression or feelings of sadness.
If you have low energy, certain vitamins and supplements may help improve your symptoms. Low levels of B vitamins, vitamin D, and iron can cause fatigue. But taking these vitamins is only likely to improve your energy if your levels are low. Ginseng, coenzyme Q10 (CoQ10), and ashwagandha may all help increase energy.
Individuals experiencing a deficiency often report feeling unusually tired or weak, even after adequate sleep. This symptom arises because a lack of B12 impairs the production of red blood cells, leading to fewer cells to transport oxygen throughout the body.
As breakfast is so often the largest (and most important) meal of the day, the morning is a prime time to take the sunshine vitamin. Plus, vitamin D levels tend to be highest during the day because of our exposure to the sun. So, taking it in the morning sets you up for further success.
In daytime workers, vitamin D deficiency was closely related to shorter duration of total sleep time (odds ratio [OR]: 3.07, 95% confidence interval [CI]: 1.51–6.26, P = . 002) and higher risk of excessive daytime sleepiness (OR: 2.20, 95% CI: 1.30–3.74, P = . 003).
Supplementing vitamin B6 may improve sleep quality and duration. A 2019 study also found that taking a supplement of magnesium, melatonin, and vitamin B complex for 3 months improved sleep and helped treat insomnia.
When vitamin D levels are low and the body isn't able to properly absorb calcium and phosphorus, there is an increased risk of bone pain, bone fractures, muscle pain, and muscle weakness. In older adults, severe vitamin D deficiency (levels less than 10 ng/mL) may also contribute to an increased risk of falls.
The body makes vitamin D in a chemical reaction that occurs when sunlight hits the skin. This reaction produces cholecalciferol, and the liver converts it to calcidiol. The kidneys then convert the substance to calcitriol, which is the active form of the hormone in the body.
Vitamin D absorption can be prevented by limited sun exposure (dark skin, sunscreen, covering up, indoor lifestyle), medical conditions (celiac, Crohn's, cystic fibrosis, liver/kidney disease, obesity), certain medications (steroids, anti-seizure drugs, weight-loss drugs), and even some nutritional factors like low magnesium, with fat malabsorption issues and obesity being major culprits for preventing both dietary and sun-derived vitamin D from working effectively.