Vitamin D is created from direct sunlight on the skin when outdoors. It is an essential nutrient needed to keep bones, teeth and muscles healthy. A lack of vitamin D can lead to bone deformities such as rickets in children, and bone pain caused by a condition called osteomalacia in adults. Pain in a particular part of the body can also signal a person is lacking the sunshine vitamin.
Several large observational studies have found a relationship between a deficiency and chronic lower back pain.
One study examined the association between vitamin D levels and back pain in more than 9,000 older women.
The researchers found that those with a deficiency were more likely to have back pain, including severe back pain that limited their daily activities.
In one controlled study, people with vitamin D deficiency were nearly twice as likely to experience bone pain in their legs, ribs or joints compared to those with blood levels in the normal range.
In addition to back pain, people with a vitamin D deficiency may have an increased risk of chronic headaches, according to a study from the University of Eastern Finland.
The findings, published in Scientific Reports, were the result of an analysis of serum vitamin D levels and occurrence of headache in approximately 2,600 men aged between 42 and 60 years in 1984-1989.
In 68 percent of these men, the serum vitamin D level was below 50 nmol/l, which is generally considered the threshold for vitamin D deficiency.
Chronic headache occurring at least on a weekly basis was reported by 250 men, and men reporting chronic headache had lower serum vitamin D levels than others.
When the study population was divided into four groups based on their serum vitamin D levels, the group with the lowest levels had over a twofold risk of chronic headache in comparison to the group with the highest levels.
Chronic headache was also more frequently reported by men who were examined outside the summer months of June through September.
People may also experience a certain problems with their immune system.
According to the NHS, between October and early March, people in the UK don’t get enough vitamin D from sunlight, which heightens the risk of a vitamin D deficiency.
The Department of Health recommends that a person takes a daily supplement containing 10 micrograms of vitamin D throughout the year if they:
- Aren’t often outdoors – for example, if you’re frail or housebound
- Are in an institution like a care home
- Usually wear clothes that cover up most of their skin when outdoors
“If you have dark skin – for example you have an African, African-Caribbean or south Asian background – you may also not get enough vitamin D from sunlight,” noted the health body.
The NHS warns against taking too many vitamin D supplements, however: “Taking too many vitamin D supplements over a long period of time can cause too much calcium to build up in the body (hypercalcaemia).”
This can weaken the bones and damage the kidneys and the heart, the health site says.
Other sources of vitamin D
People can also top up the vitamin by eating certain foods.
- Oily fish – such as salmon, sardines, herring and mackerel
- Red meat
- Egg yolks
- Fortified foods – such as most fat spreads and some breakfast cereals