1. Being sick or getting infections often
One of vitamin D’s most important roles is keeping your immune system strong so you’re able to fight off viruses and bacteria that cause illness.
It directly interacts with the cells that are responsible for fighting infection.
If you often become sick, especially with colds or the flu, low levels of vitamin D may be a contributing factor.
Several large observational studies have shown a link between a deficiency and respiratory tract infections like colds, bronchitis, and pneumonia.
A number of studies have found that taking vitamin D supplements at a dosage of up to 4,000 IU daily may reduce your risk for respiratory tract infections.
Vitamin D plays an important role in immune function. One of the most common symptoms of a deficiency is an increased risk of illness or infections.
2. Fatigue and tiredness
Feeling tired can have many causes, and vitamin D deficiency may be one of them.
Unfortunately, it’s often overlooked as a potential cause.
Case studies have shown that very low blood levels of vitamin D can cause fatigue that can have a severe negative effect on quality of life.
Excessive fatigue and tiredness may be a sign of vitamin D deficiency. Taking supplements may help improve energy levels.
A depressed mood may also be a sign of vitamin D deficiency.
In review studies, researchers have linked vitamin D deficiency to depression, particularly in older adults.
In one analysis, 65% of the observational studies found a relationship between low blood levels and depression.
Some studies have shown that giving vitamin D to people who are deficient helps improve depression, including seasonal depression, which typically occurs during the colder months.
Depression is associated with low vitamin D levels, and some studies have found that supplementing improves mood.
4. Bone and back pain
Vitamin D helps maintain bone health in a number of ways.
For one, it improves your body’s absorption of calcium.
Bone pain and lower back pain may be signs of inadequate vitamin D levels in the blood.
Large observational studies have found a relationship between a deficiency and chronic lower back pain.
One study in 98 people with lower back pain found that increased pain severity was associated with lower levels of vitamin D.
Another review of 81 studies also found that people with arthritis, muscle pain, and chronic widespread pain tended to have lower levels of vitamin D compared with people without these conditions.
Slow healing of wounds after surgery or injury may be a sign that your vitamin D levels are too low. Low blood levels of vitamin D may be a cause or contributing factor to bone pain and lower back pain.
5. Impaired wound healing
In fact, results from a test-tube study suggest that the vitamin increases the production of compounds that are crucial for forming new skin as part of the wound-healing process.
One review of four studies found that vitamin D deficiency compromised certain aspects of healing in people who had dental surgery.
It’s also been suggested that vitamin D’s role in controlling inflammation and fighting infection is important for proper healing.
One analysis looked at patients with diabetic foot infections.
It found that those with severe vitamin D deficiency were more likely to have higher levels of inflammatory markers that can jeopardize healing.
Unfortunately, there is very little research about the effects of vitamin D supplements on wound healing in people with a deficiency at this point.
However, one study involving 60 people with diabetic foot ulcers found that taking a vitamin D supplement for 12 weeks significantly improved wound healing compared with a control group.
Inadequate vitamin D levels may lead to poor wound healing following surgery, injury, or infection.
Read more at healthline.com