Feeling the seasonal Scandi blues? These are 5 key signs that indicate you’re Vitamin D deficient

At this time of year, when the days are darker and we spend less time outdoors, many of us risk becoming vitamin D deficient. Particularly prevalent in European and Asian communities, research shows that one billion people around the world are vitamin D deficient, a situation that has ramifications for our health (more on which later).

It is well known that sun exposure is the easiest way to stimulate the production of vitamin D in the body, which is why we’re particularly vulnerable to deficiency in the dark, winter months. “The NHS recommends supplementing with vitamin D3 from autumn and throughout the winter months for this reason,” explains Rhian Stephenson, nutritionist, naturopath and founder of Artah.

Without sunlight, which (let’s face it) can be rare in the UK, there are other ways of ensuring we get our vitamin D fix. “Most foods are poor sources of vitamin D, but the ones that do offer it include salmon, swordfish, tuna, full fat dairy that’s fortified with vitamin D, sardines, beef liver, cod liver oil and egg yolks,” says Stephenson, who emphasises that eating such foods won’t deliver adequate levels, but will help. Those who eat a vegan diet, she warns, are particularly at risk of vitamin D deficiency.

When it comes to supplementing, which is key to prevent deficiency, Stephenson says that recommendations vary by country. “In the US and Canada, the RDA is 600IU per day for adults and 800IU per day for individuals over 70, while in the UK the RDA is 400IU,” she says. “The bare minimum is 400IU – in my experience, this is too low to correct an insufficient or deficient status.”

It’s also worth noting that supplements are available in D2 and D3 form, but you should always opt for D3. “In addition, look for supplements that are paired with vitamin K2, like our Essential D3/K2, because they work together to optimise calcium metabolism. Without K2, calcium can accumulate and deposit in arteries, rather than being transported to our bones,” she adds.

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Optimal vitamin D levels are essential for systemic health. “It regulates cellular growth and gene expression (essential for cancer prevention), improves cell differentiation and is involved in immunity, fertility, muscle strength, hormone balance, sexual health, energy, mood and more,” says Stephenson. Put simply, it’s essential for all-round health and wellbeing.

Vitamin D deficiency impacts both physical and mental health. We all know about osteoporosis, but low levels are also linked to poor immunity, depression and back pain – to name three problems. “It’s linked to poor outcomes across the board – from autoimmune conditions, Covid-19 and cancer to general immunity, hormone health and mood disorders,” says Stephenson. Hypertension, diabetes, fibromyalgia and neurological disorders, such as multiple sclerosis, are all also linked to vitamin D deficiency.

The only way to truly know if you are vitamin D deficient is to have a blood test via your GP. However, there are also signs and symptoms you can look out for.

One of the most common symptoms when you have a severe vitamin D deficiency is a feeling of chronic, profound or irremediable fatigue. To add to that, poor sleep is another symptom.

Some studies have shown a correlation between frequent muscle pain and weakness, and vitamin D deficiency. Meanwhile bone and joint pain is common, as vitamin D is essential for the body to absorb calcium – without it, increased fragility and pain may occur.

It’s essential for healthy hair that grows optimally. A deficiency can cause hair to fall out or slow growth because a deficiency intervenes with a follicle’s life cycle. Alopecia is also believed to be related to vitamin D insufficiency.

Vitamin D deficiency is associated with a weak immune system. If you’re often ill and don’t know why, consider getting a blood test.

Scientific research shows that vitamin D may play a key role in balancing our mood and minimising the risk of depression. Low levels can contribute to seasonal affective disorder and are often associated with feelings of overwhelm, sadness, anxiety, forgetfulness and sadness.

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