Vitamin D and why you most definitely need to supplement
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.
Your body makes vitamin D when it’s exposed to sunlight. 80 to 100 percent of the vitamin D we need comes from the sun. The sun exposure that makes our skin a bit red (called 1 minimum erythemal dose) produces the equivalent of 10,000 to 25,000 international units (IU) of vitamin D in our bodies.
The problem is that most of us aren’t exposed to enough sunlight.
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.
Overuse of sunscreen is only one reason why so many are Vitamin D deficient. While these products help protect against skin cancer, they also block a massive 97 percent of your body’s vitamin D production.
Ageing skin produces less vitamin D. The average 70 year-old person creates only 25 percent of the vitamin D that a 20 year-old does. Skin colour makes a difference. People with dark skin also produce less vitamin D. Those with severe deficiencies are people that keep their skin covered all the time.
Although possible to obtain vitamin D from food sources, 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.
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.
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.
The reference ranges for vitamin D in the UK (2022) 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.
- 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.
- 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.
- 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.
- 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.
With all these causes of vitamin D deficiency, and how hard it is to get from diet alone, you can see why supplementing with enough of this vitamin is so important.