Are you feeling more tired than normal at the moment? Maybe your aches and pains seem worse now you’re not getting your full quota of vitamin D from the sun’s rays? If this is the case, your instinct may be to get a vitamin D test.
If we follow the trends identified in studies, one in five people in the UK could have low vitamin D levels1 . It’s a common deficiency, but how important is it to be diagnosed with a vitamin D test?
What is vitamin D deficiency ?
Without a sufficient supply of vitamin D, your body may not be able to properly absorb the right amounts of calcium and phosphate. These two nutrients are important for keeping bones, teeth and muscles healthy. As a result, a mild to moderate vitamin D deficiency can cause bone pain and osteoporosis (weakening of the bones.) A more severe deficiency can cause children to get rickets and adults may develop osteomalacia 2/3 .
Vitamin D also offers important support to your immune system, with some research showing that low levels of this nutrient can increase your risk of infection and disease 4 .
What are the symptoms of low vitamin D?
It’s common to experience no symptoms or only vague niggles. But any of the following can be an indicator4 :
- Tiredness and fatigue
- Muscle aches and pains
- A general sense of not feeling well
- Muscle weakness (e.g. that can cause problems climbing stairs)
- Bone pain (most often noticed in shin bones and ribs, but also the lower back, hips, pelvis, thighs and feet)
Can you check vitamin D levels at home?
If you suspect your fatigue and aching muscles could be down to dwindling D levels, the only accurate way to reliably diagnose a deficiency is to take a vitamin D test. Your doctor can arrange a simple blood test for vitamin deficiency to make the diagnosis.
Vitamin D home tests are also available. These rely on a finger prick blood sample.
Can you rely on a vitamin D test kit ? 6
At-home tests are convenient when it’s difficult to attend a surgery appointment, but the following should be considered.
- User error. This is a possibility with at-home tests and can affect results. Make sure you follow guidance closely.
- Understanding results. A test can show you are deficient, but without the support of a nutritionist or doctor it can be difficult to interpret what your results mean for you. For example, in the context of your age, gender and other personal factors. You’ll also need to seek further advice on the best course of action to take.
What is vitamin D listed as on a blood test?
Measuring the concentration of 25-hydroxyvitamin D in your blood is the best way to identify a vitamin D deficiency 7. This is measured in in nanomoles/litre (nmol/L) or nanograms/millilitre (ng/mL). A level of 20 ng/mL to 50 ng/mL is a healthy range. If less than 12 ng/mL is detected, it implies a vitamin D deficiency8 .
Does a CBC test show vitamin D deficiency?
A complete blood count (CBC) is a common blood test that gives a snapshot of your overall health. It can be helpful in identifying a number of health conditions, including vitamin deficiencies 9 .
What can you do if you are vitamin D deficient?
The best way for your body to make vitamin D is through exposure to the sun. Sunlight is unfortunately an unreliable commodity during the long, dark days of the UK autumn and winter. So, during these times of year, you need to get more vitamin D from your diet. However, it’s difficult to get enough vitamin D from food alone. The NHS suggests taking a daily supplement containing 10 micrograms of vitamin D year-round.
Last Updated: 17th November 2020
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Author: Donia Hilal, Nutritionist
Donia started her career as a freelance nutritionist, later she joined Nestle as their Market Nutritionist to help support their healthier product range, before joining the team at Holland & Barrett in January 2018. Donia has 6 years experience as a Nutritionist and also works with clients on a one to one basis to support their goals which include weight loss, prenatal and postnatal nutrition and children’s health. Donia has a special interest in; weight management, plant-based nutrition, pregnancy nutrition, special diets and disease risk reduction. Donia’s LinkedIn profile |
Sources:
1 https://patient.info/bones-joints-muscles/osteoporosis-leaflet/vitamin-d-deficiency
2 https://www.nhs.uk/news/lifestyle-and-exercise/news-analysis-health-claims-about-vitamin-d-examined/
3 https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/
4 https://pubmed.ncbi.nlm.nih.gov/21527855/
5 https://patient.info/bones-joints-muscles/osteoporosis-leaflet/vitamin-d-deficiency#nav-0
6 https://www.verywellhealth.com/vitamin-d-at-home-test-covid-5083394
7 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2912737/
8 https://www.healthline.com/health/25-hydroxy-vitamin-d-test#results
9 https://familydoctor.org/complete-blood-count-cbc/