Learn about the health benefits of Vitamin D and how to avoid deficiency
Vitamin D is known as the “sunshine vitamin”; however, it’s not strictly a vitamin (it’s a hormone) as it can be synthesised on the skin when the body is exposed to sunlight.
Food sources of vitamin D are only required in the absence of adequate sunlight.
Learn why vitamin D is important, what it does in the body, the deficiency signs and symptoms to look out for and how to maintain optimal vitamin D levels.
How to get Vitamin D
The body creates vitamin D on the skin when exposed to direct sunlight; the ultraviolet B (UVB) rays from the sun stimulates vitamin-D receptor cells in the skin that triggers a chemical reaction in the body, enabling it to produce vitamin D3. Vitamin D can be stored in the liver for four months.
In the UK and Ireland, people can top up their vitamin D levels during spring and summer from late March/ early April until late September. Vitamin D levels tend to dip during the winter months due to the darker days and less sunlight exposure.
Experts recommend short bursts of unprotected sun exposure (around 5 – 10 minutes), a few times per week for fairer skin types, in order to maintain vitamin D levels. For those with darker skin tones, it can take three to six times longer to produce the same amount of vitamin D3 due to their skin pigmentation.
Sunscreens block the absorption of vitamin D on the skin. Furthermore, commercial sunscreens contain toxic, carcinogenic ingredients that can wreak havoc with your health. Research has shown that chemicals in sun creams can disrupt hormones and metabolism, cause allergies and damage healthy cells; they have also been linked to cancer (especially the chemical oxybenzone).  Learn more about the toxic chemicals in sun creams and how to protect the skin naturally.
It is also possible to obtain vitamin D from food sources, although it is difficult to get enough of it from the diet. There are two types of vitamin D food sources: D2 (ergocalciferol D2) from plant sources which is found in sun-exposed mushrooms and D3 (cholecalciferol D3) from animal sources found in cod liver oil, oily fish (herring, mackerel, sardines, wild-caught salmon) and egg yolks (opt for organic).
What happens when your vitamin D is low?
The signs and symptoms of vitamin D deficiency include:
- Bone pain and bowing of lower limbs due to rickets (in children) and osteomalacia (in adults). This is caused by demineralised bones (lack of vitamin D and calcium) which makes bones become soft and weak, often leading to bone deformities.
- Osteoporosis – this is when bones become weak and fragile, increasing the risk of breaks and fractures.
- Poor immune function (frequent bouts of illness) including allergies and autoimmunity.
- Severe asthma in children – studies have shown that asthmatic children tend to have low serum vitamin D levels and there is a strong link between reduced lung function in children and vitamin D deficiency.
- Insomnia and sleep issues as vitamin D is linked to sleep quality and duration.
- Mood issues and depression as vitamin D is needed for serotonin production (the hormone that regulates mood and feelings of wellbeing).
- Menstrual irregularities and fertility problems – vitamin D helps to modulate hormone levels and a lack of vitamin D can change a woman’s menstrual cycle significantly and impair semen quality (affecting both sperm production and motility).
- Musculoskeletal pain that is non-specific.
Causes of Vitamin D deficiency
- Inadequate intake of vitamin D or exposure to sunlight.
- Excessive animal protein or calcium intake can lower blood levels of vitamin D.
- Lack of dietary fats (i.e., consuming a low-fat diet) as vitamin D is a fat-soluble vitamin, meaning it gets absorbed along with fats in the diet.
- Low magnesium levels as magnesium is a co-factor nutrient for vitamin D synthesis.
- Poor liver function due to excess alcohol, drugs and caffeine consumption or toxin overload which compromises the conversion of vitamin D in the body.
- Malabsorption issues and compromised digestive function in conditions like coeliac disease, Crohn’s disease, dysbiosis (an imbalance of gut bacteria) and cystic fibrosis which causes poor intestinal absorption of vitamin D.
- Reduced kidney function (which is common in the elderly) as the kidneys are unable to convert vitamin D to its active form.
- Overeating and eating too much junk food. Obesity can lead to vitamin D deficiency as extra fat cells alter the release of vitamin D into the bloodstream. For every 10% increase in BMI (Body Mass Index), there is a 4.2% reduction in blood vitamin D levels.
- Those with darker skin tones are at a higher risk of vitamin D deficiency as they have more melanin pigments in their skin which reduces the skin’s ability to produce vitamin D from sunlight.
- Breastfeeding without adequate sunlight or supplementation means less vitamin D will pass through the breast milk to the baby.
Health benefits of Vitamin D
Vitamin D is commonly known for its key function of maintaining bone health; however, it also performs many other functions in the body.
It is a vital co-factor nutrient for muscle contraction and bone metabolism. Vitamin D aids calcium absorption, keeps calcium and phosphorus levels balanced in the body and strengthens muscles. Research suggests there is a strong correlation between chronic pain and vitamin D deficiency, and supplementation of vitamin D can reduce inflammation and pain in the body.
Being a powerful immune modulator, Vitamin D supports immune function and can improve the body’s antimicrobial defence system. It also helps regulate immune cells and reduce inflammation to promote a healthy immune response. Those with allergies, constant infections (viral and bacterial) and autoimmune conditions should see a natural health therapist to get their vitamin D levels checked; supplementation may be required.
Vitamin D has shown to have anti-cancer properties and the ability to regulate gene cells, enhancing anti-tumour activity of immune cells. It also inhibits angiogenesis (the formation of new blood vessels for tumour cells), preventing cancer cells from receiving the oxygen and nutrients they need to grow.
In the gastrointestinal system, vitamin D plays a role in keeping the gut microbiome healthy (by increasing beneficial gut bacteria), protecting the gut barrier and regulating inflammation, especially of the gut lining (mucosa). Vitamin D can help with inflammatory bowel conditions like ulcerative colitis and Crohn’s disease.
Vitamin D is also involved in blood sugar metabolism; it aids the secretion of insulin (the hormone that helps transport glucose into cells) and increases insulin sensitivity in cells. Vitamin D is beneficial for individuals with type 1 and type 2 diabetes. Those with type 2 diabetes tend to have lower vitamin D levels.
How to tell if you have Vitamin D deficiency
If you’re experiencing any of the symptoms above or you live in colder climates where your exposure to sunlight may be limited, it’s advisable to get your vitamin D levels checked by doing a simple blood test. Speak to a natural therapist such a naturopath or nutritional therapist who can organise this for you and provide advice regarding supplementation.
The reference ranges for vitamin D in the UK are as follows:
- Below 25 nmol/L indicates deficiency
- 25 – 50 nmol/L is sub-optimal
- 50 nmol/L and above is considered normal
- 75 – 125 nmol/L is the optimal range for vitamin D
Re-testing blood levels every four months (after supplementation) is recommended so your vitamin D dosage can be adjusted accordingly. This should be done under the guidance of a practitioner.
How to increase your Vitamin D levels naturally
- Go for a walk in the sun.
- Increase your intake of organic vegetables which contain important co-factor nutrients and eat more vitamin D containing foods including sun-exposed mushrooms, organic egg yolks and oily fish like sardines and mackerel.
- Cut down on meat, animal proteins (including dairy products) and sugar. Learn more about hidden sugars and the effect sugar has on health.
- Include healthy fats in your diet such as avocado, extra virgin olive oil, nuts, flaxseeds, chia seeds and flaxseed oil.
- Avoid alcohol and caffeine. Try a coffee alternative such as turmeric latte or caffeine-free chicory root coffee. Learn more about the negative effects of coffee.
- Boost your magnesium levels through diet and supplementation. Food that are high in magnesium include leafy green vegetables (kale, spinach, rocket), almonds, pumpkin seeds and cashews. Learn more about the benefits of taking magnesium.
- Support your liver by reducing your toxic load and doing a detox. Drinking warm water with fresh lemon juice first thing in the morning is a great way to cleanse the liver. Here are more ways to support liver health.
- Improve gut health and boost beneficial gut bacteria with probiotics. Fermented foods like sauerkraut and kimchi, garlic and broccoli are great for the gastrointestinal system. Learn more about foods for gut health.
Boost health naturally with Vitamin D
Vitamin D is an essential nutrient for bone and muscle health, the immune system, gut health and blood sugar metabolism. Low vitamin D levels can lead to a host of health issues including frequent illness, asthma, infertility, mood disorders and osteoporosis. As a Natural Chef, you will not only learn the best food sources of Vitamin D, but also how to enhance the bioavailability through food combining, optimal ranges and doses as well as supporting the conditions of which low vitamin D status is associated with.