There is more to vitamin D than just contributing to bone health in adults and bone development in children. Studies are revealing links between vitamin D and the reproductive system, cardiovascular system, immune system and mental health.

This has now raised the question of just how much vitamin D is required to maintain good health.

How much is right for you will depend on several factors, including your stage of life. For example, both the elderly and pregnant women are more at risk of developing symptoms of depression with a deficiency in vitamin D.

Depression makes managing diabetes difficult.

Why might I be vitamin D deficient?

The Australian Health Survey (2011-2012) found that 23% of Australian adults were vitamin D deficient. This included 17% who were mildly deficient, 6% who were moderately deficient and less than 1% who were severely deficient.

How do you know if you have healthy vitamin D levels?

Begin by assessing if you are at risk of a vitamin D deficiency. Those at risk include:

• People who have had skin cancer or are a high risk of skin cancer and avoid direct sunlight on the skin.
• Individuals who wear clothing that covers and conceals the skin.
• Naturally very dark-skinned people.
• People who spend long hours indoors.
• The elderly with a reduced ability to metabolise vitamin D.
• People who are overweight, as fat stores allows more storage of vitamin D in body fat compartments.
• Infants and babies who rely on vitamin D deficient mothers for their supply of vitamin D.
• People who take medication that interacts with Vitamin D metabolism or accelerates its degradation.
• Those with medical conditions or medications that cause skin sensitivity which leads to sun avoidance.

What should my vitamin D level be?

Contact your doctor if you feel that you are at risk. Your doctor can refer you for a blood test. At present vitamin D levels of 50-60nmol/L are recommended for adults to maintain bone health and muscle strength.

In future this recommended level may become more tailored to suit the individual and their health difficulties. For instance, a recent small study reported improvements in insulin sensitivity and insulin resistance in response to improving low levels of vitamin D. This small study of South-Asian women living in New Zealand suggests that ethnicity may play a role in how vitamin D supplements is used by the body. More research is needed as ethnicity is not the only factor that affects your vitamin D level.

How do I increase my vitamin D level?

There are numerous ways you can obtain vitamin D:

1. Expose your skin to the sun’s ultraviolet B waves. This begins a metabolic process that also involves the liver, kidneys and calcium. This process produces vitamin D3, or cholecalciferol. The amount produced in this way depends on a number of factors including skin pigmentation, use of sunscreen, latitude, season and age. Be aware that it is ultraviolet A waves that passes through glass, not ultraviolet B waves. This means that sitting in the sun behind glass will not help you increase your vitamin D levels.
2. Eating eggs, liver, and fatty fish like salmon, herring and mackerel will increase your Vitamin D3 levels.
3. You can find vitamin D2 in certain foods. It naturally occurs in plants, fungi and yeast.
4. Some foods like milk products may be fortified with vitamin D3.
5. If necessary, a vitamin D tablet or injection supplement can be taken under medical supervision.

More and more studies are showing just how important vitamin D is for good health. While those sun rays through the glass may feel warm and comforting, they are not actually helping you make vitamin D. If necessary, see your doctor to check your levels as taking supplements requires medical supervision.

By Amanda Callaghan RN CDE

References:

Australian bureau of Statistics (ABS) 2011 – 2013. Australian Health survey: Biomedical Results for Nutrients. https://www.abs.gov.au/statistics/health/health-conditions-and-risks/australian-health-survey-biomedical-results-nutrients/latest-release

David Scott, Aya Mousac, Negar Naderpoorc, Maximilian P.J. de Courtend, Robert Scragge,

Barbora de Courtenc (2019) Vitamin D supplementation improves waist-to-hip ratio and fasting blood glucose in vitamin D deficient, overweight or obese Asians: A pilot secondary analysis of a randomised controlled trial Journal of Steroid Biochemistry and Molecular Biology 186 (2019) 136–141  https://doi.org/10.1016/j.jsbmb.2018.10.006

Gleicilaine A. S. Casseb1  · Manuella P. Kaster1  · Ana Lúcia S. Rodrigues (2019) Potential Role of Vitamin D for the Management of Depression and Anxiety CNS Drugs 33:619–637 https://doi.org/10.1007/s40263-019-00640-4

Jorde, R, Grimnes, G (2020), Increased calcium intake is associated lower serum 25-hydroxyvitamin D levels in subjects with adequate vitamin D intake: a population-based observational study. BMC Nutrition, https://doi.org/10.1186/s40795-020-00381-4

National Cancer Control Policy (2016) https://wiki.cancer.org.au/policy/Position_statement_-_Risks_and_benefits_of_sun_exposure

Von Hurst, W. Stonehouse, J. Coad (2010) Vitamin D supplementation reduces insulin resistance in South Asian women living in New Zealand who are insulin resistant and vitamin D deficient–a randomised, placebo-controlled trial, Br. J. Nutr. 103 (04) 549–555.