Everything You Need To Know About Vitamin D

Guest post from local Nutritional Therapist Sarah Gale

There is so much to love about winter. Snuggling on the sofa, hot cups of tea, the sound of rain lashing against the windows, the odd dry crisp sunny day to stretch your legs and get out for a long walk. What is less pleasurable about winter is the dark mornings, cold evenings, brisk winds and increasing rounds of cold and flu. As well as the increased risk for vitamin D deficiency.  

Vitamin D, often known as the sunshine vitamin, is produced naturally under the skin in response to sunlight... and it's not very aptly named, as it is actually a hormone! In Guernsey, there is enough sunlight between April and September to produce adequate amounts of vitamin D for most of us, however in winter we need to look at other sources to maintain our levels.

Let's take a look at why you need vitamin D, signs you might be deficient and what you can do about it. 


Winter Sun


Why is Vitamin D Important?

Vitamin D is a miracle vitamin (or hormone) that supports our health in a myriad of ways. It provides support for:

  1. Immune health: By supporting the immune system and fighting infections.
  2. Bone and muscle health: By regulating calcium levels and the activity of bone building cells which helps to prevent osteoporosis.
  3. Brain health: By playing a crucial role in neurological health and cognitive function.
  4. Heart health: By helping to prevent calcium build up in the arteries, normalise blood pressure and reduce inflammation.
  5. Skin health: By helping to prevent excess cell proliferation (increase in number of cells) which is found in conditions like psoriasis or eczema.
  6. Blood sugar balancing and insulin control: By helping to regulate blood sugar and prevent insulin resistance.
  7. Mood: Recent research has shown that vitamin D can have a positive effect on mood, with depression being associated with low vitamin D levels. Whilst the exact mechanism remains unclear, it is postulated that vitamin D may influence serotonin, our happy hormone, helping to improve our mood.


Why Might Your Vitamin D Levels Be Low?

In the winter, this is likely due to a lack of sunlight exposure. However, there are several other reasons which can contribute to low vitamin D levels all year round:

  1. The use of sunscreen as it blocks UV rays which hinders the production of vitamin D under the skin.
  2. Age. As we get older we become less efficient at converting sun rays into vitamin D and our kidneys are not as good at turning it into the active form of calcitriol.
  3. Being overweight or obese as our fat cells hoover up vitamin D, so it ends up being stored in fat instead of being used by the rest of the body.
  4. Darker skin tones make less vitamin D due to the higher levels of melanin in skin that protect against UV rays.
  5. Lack of general sunlight exposure, which is common in night shift workers and those who are housebound. In fact, we will all likely have experienced less sunlight than usual due to lockdowns.
  6. Genetics also play a factor reducing either the absorption or utilisation of vitamin D in the body.
  7. Pregnant and breastfeeding women have an increased risk of deficiency.


Are You Concerned You Might Be Vitamin D Deficient?

Here are 10 signs that you might be:

  1. You suffer with depression or anxiety (including recent changes in your mood or irritability).
  2. You have soft bones (low bone density).
  3. You are feeling tired all the time or noticed a decreased performance in usual activities.
  4. You have muscle cramps or muscle weakness.
  5. You suffer with joint pain.
  6. You have difficulty regulating your blood sugar levels or experience the post lunch energy crash.
  7. You have lowered immunity and catch every bug going around.
  8. Your wounds are slow to heal.
  9. You have low calcium levels in the blood.
  10. You have experienced unexplained weight gain.




How To Increase Your Vitamin D Levels In Winter

  1. Supplement with Vitamin D3 (not vitamin D2). Work with your GP or health practitioner to determine the correct dose for you. Make sure you also supplement with the other nutrients that vitamin D3 requires to work optimally including magnesium, vitamin K2, vitamin A, boron and zinc. A good multi plus vitamin D3 with K2 should cover this. As a safety note, please do check with your GP or health practitioner before starting any new supplements if you’re on medication or have a health condition.
  2. Top up your levels by eating naturally vitamin D3-rich foods like oily fish (salmon, sardines, fresh tuna, trout, halibut, mackerel, etc.), egg yolks and organic liver. Unfortunately, fortified foods don’t quite have the same benefit as they contain vitamin D2 which is less effective  raising and maintaining your vitamin D levels in the blood. Remember, it is not enough to rely on food alone to up your vitamin D levels to make sure you are supplementing too if you don’t have access to adequate sunlight.
  3. Book yourself some winter sun, if you can! If you can’t then you will need to rely on supplementation during the winter months and take advantage of the sun in summer instead. During summer, be sensible to prevent sunburn as skin exposure needs to be without sunscreen for vitamin D production to occur. It is recommended to avoid the hottest times of the day and limit your exposure to short periods of time depending on your skin type.


How To Support Your Vitamin D Levels

In my opinion, everyone should get their vitamin D levels tested in winter. Your GP is able to check your vitamin D levels for you or you can also purchase a home kit test for £29. It’s a finger prick test, so you can do it easily at home, just make sure you get guidance on how much to supplement with safely. The kits are available to purchase from the NHS - I do not have any affiliation with the kits, they are just something I recommend to clients as an easy and relatively cheap option to get your levels tested.


Meet Sarah...


Expert Sarah


Sarah Gale is a Registered Nutritional Therapist, Clinical Nutritionist DipION mBANT and hormone expert and helps women who just can’t lose weight break free of the diet cycle, rebalance their hormones and feel confident in their own skin again.

After a lifetime a hating her body and chronic yo-yo dieting, Sarah realised that yo-yo diets didn’t have the answers and by balancing her hormones, fixing her metabolism and working on her mindset she could finally lose the weight and get her self-confidence back.

Get in touch with Sarah if you would like to discuss your vitamin D profile and recommended levels.


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