We all know that vitamin D is essential for good health, but are you getting enough?

It is an essential, fat soluble nutrient which is involved in the function of each body system, not least the immune system, partly by functioning as a hormone.1 It is likely that low levels of vitamin D may play a role in many of the health issues which are unfortunately so prevalent nowadays.

Statistics show that up to 25% of the general UK population may be deficient in vitamin D.2 The body is able to produce large quantities of vitamin D when exposed to UVB light, giving vitamin D its name as the ‘sunshine vitamin’. Dietary sources include cholecalciferol (vitamin D3 from predominantly animal sources e.g. eggs, oily fish) and ergocalciferol (vitamin D2, from plant sources e.g. mushrooms, tofu). In the modern world, it is common to spend extensive time indoors, overuse sunscreen, and have a poor quality diet lacking in these foods, all of which can contribute to low levels of vitamin D. Certain individuals may be especially vulnerable to deficiency, including:

  • Those who follow a vegan or vegetarian diet3
  • Pregnant and breastfeeding women
  • Breast-fed infants and young children
  • Individuals with dark4 or covered skin5
  • People with digestive impairments, such as Inflammatory Bowel Disease (IBD) or fat malabsorption disorders such as gallbladder removal/dysfunction.6
  • The elderly, since vitamin D synthesis in the skin becomes less efficient with advancing age7
  • People taking medications that can significantly deplete vitamin D status e.g. steroids8 and fat blocking medications used for weight loss (e.g. Orlistat9).

For example, if you’re on a few medications, your work life is leaving you stressed and tired with a few bugs going around at home, you may benefit from some vitamin D.

So, why is vitamin D essential to health, and why can vitamin D deficiency be so detrimental to our health and wellbeing?

  • Sex hormones: vitamin D may have a beneficial effect on Premenstrual Syndrome (PMS) according to preliminary research.10,11 On the other end of the spectrum, having excess androgens (e.g. testosterone), which is linked with various conditions such as polycystic ovary syndrome (PCOS),12 can also be supported by vitamin D, with research showing that vitamin D may help reduce these levels.13
  • Energy: vitamin D deficiency is associated with pronounced fatigue, with individuals suffering from chronic fatigue syndrome showing low levels of vitamin D in research.14
  • Structure: menopausal women are at risk of conditions such as osteoporosis or osteopenia due to the decline in oestrogen. Given that vitamin D is essential for bone health,15 it can be a great idea to increase intake as a preventative measure for perimenopause. Vitamin D may also be supportive for severe hair loss conditions such as alopecia,16 alongside measures to support stress since it is a common driver of hair problems.17
  • Nervous System: vitamin D has the potential to protect nerve cells18 and support conditions such as MS,19 depression,20 and cognitive decline.21 Vitamin D deficiency may also decrease levels of dopamine, a neurotransmitter involved in our emotions and pleasure. Mood swings and psychological disorders such as bipolar may consequently be related to low vitamin D.22
  • Immunity: vitamin D can reduce the risk of infection23 in those with autoimmunity, modulate the underlying disease process and reduce the risk of developing it in the first place.24 Individuals with rheumatoid arthritis may benefit from increased dietary and supplementary intake to help them manage their symptoms.25 The anti-inflammatory properties of vitamin D can also be useful for conditions such as eczema,26 with research showing that low maternal vitamin D intake may increase the likelihood of allergies in offspring.27
  • Digestion: a more permeable gut wall (so-called ‘Leaky Gut), driven by gluten and lectins, contributes to an impaired immune system.28 Vitamin D may support healthy junctions in the gut lining and the healing process,29 alongside other nutrients such as zinc,30 vitamin A,31 and L-glutamine.32 Poor vitamin D status is also associated with an increased risk of chronic digestive conditions, notably Crohn’s Disease33 and Ulcerative Colitis.34

As you can see, vitamin D deserves its place in the nutritional first aid kit.