The sunshine vitamin plays a vital role in overall health, but it needs to be in balance
Vitamin D, known as the `sunshine vitamin’ because sunlight helps our bodies to produce it, is essential for maintaining strong bones and a healthy immune system, as well as keeping muscles and brain cells working. Too little or too much can have adverse effects on your health.
“Vitamin D involves a complex interplay between environmental and individual factors. Either deficiency or overdose of vitamin D can affect overall health, yet understanding individual vitamin D requirements can be complicated; explains Dr Jay Narainsamy, a specialist physician and endocrinologist at Netcare Park Lane Hospital in Johannesburg.
“Individual factors such as having darker skin, pre-existing illnesses, higher body mass index (BMI), cultural aspects and our modern lives’ tendency towards more indoor activities may contribute to vitamin D deficiency, even where there is bountiful availability of sunshine in a climate such as ours.
“Most studies on vitamin D deficiency have been conducted in other countries, where the climate, demographic and socio-economic factors differ from our local context. Data on South African populations is scarce and a lot more complicated to interpret, given the different sun exposures across provinces, different ethnic groups and general lack of recent information; she explains.
Learn more
You can get your vitamin levels checked at the following facilities:
- Get Tested South Africa
get-tested.co.za (Vitamin D is tested as part of the Wellness Tests) - Netcare Appointmed:
Tel: 0860 555 565
netcare.co.za / Netcare-Mobile-App - Any pathology lab such as Pathcare, Ampath or Lancet — with a referral from a GP
Why do our bodies need vitamin D?
“Vitamin D is responsible for regulating the calcium levels in our cells, therefore a deficiency of vitamin D also leads to low levels of calcium and phosphate, and in response an increased parathyroid hormone. This is detrimental to bone health and causes bone loss that may increase the risk of fractures,” Dr Narainsamy warns.
Apart from the risks to skeletal health, the effects of vitamin D deficiency are being studied in more detail for wider-ranging consequences.
“One meta-analysis suggested that vitamin D supplementation reduced cancer mortality. While cardiovascular risk reduction has not been conclusively proven, there have been studies which showed benefits in reducing blood pressure, reduction of irregular heart rhythm risk in older patients and lower incidence of heart attacks:’ Dr Narainsamy notes.
“Vitamin D is known to influence the immune system, especially the innate immunity which is the body’s first response to fighting off harmful pathogens and may, therefore, assist in protecting against respiratory illness. Conversely, vitamin D deficiency might be related to an increase in autoimmune diseases. People with diabetes and pre-diabetes can also benefit from identifying vitamin D deficiency, as it has a role in insulin regulation too:”
Some international medical societies have suggested screening for deficiency in susceptible groups, including people who are malnourished or obese, have a sedentary lifestyle, limited sun exposure or are over the age of 65, and individuals with conditions causing gastrointestinal malabsorption, liver disease or failure, renal insufficiency, fibrosis and those taking medications that alter vitamin D metabolism.
Symptoms of too little vitamin D
Most people with a vitamin D deficiency do not experience symptoms and are probably unaware of the issue, says Dr Narainsamy. Those who have a severe, prolonged deficiency may present with bone discomfort or pain in the lower back, pelvis or lower extremities, and could experience falls and impaired physical function, muscle aches, proximal muscle weakness and symmetric lower back pain (pain on both sides).
“If a person suspects they are vitamin D deficient, I recommend discussing testing with your general practitioner, or an endocrinologist or nephrologist. A medical referral is required for the test, as the result needs to be interpreted with the patient’s history and managed holistically. A thorough evaluation should be done before medication or supplementation is prescribed.”
In addition, some people may also need more detailed evaluation including testing the levels of calcium, magnesium, phosphate, 1.25 hydroxy vitamin D and parathyroid hormone.
“Dietary sources of vitamin D include oily fishlike sardines, salmon and tuna, egg yolks, beef liver and fortified cereals or plant-based dairy alternatives, as well as cod liver oil. But diet alone may not be sufficient to boost levels and lifestyle changes may be advised, along with short- or long-term supplements prescribed.”
Symptoms of too much vitamin D
Dr Narainsamy explains that vitamin D is a fat-soluble vitamin, which means it can be stored and may build up in the body. “It is important to have your levels checked regularly, especially if you are taking supplements, as vitamin D overdose can be harmful,” she advises.
If vitamin D levels become too high, this can cause hypercalcemia (when blood calcium levels become too high). This may present as nausea, dehydration, constipation, needing to urinate more frequently or in greater volumes, and kidney stones.
By: Supplied by MNA on behalf of Netcare
Photography by: Gallo/Getty Images
Also read: Consider this your intro to vitamins 101
