You’re probably thinking, a Vitamin D article outside of the winter months...Why? This article discusses why Vitamin D isn’t just essential in the winter months but throughout all seasons. So, if you’re interested in bone health, immune system support and how to ensure you are getting enough Vitamin D in your diet, then we invite you to scroll through this article.
Why is Vitamin D3 associated with Winter?
As you may already know, the best form of Vitamin D is sourced from sunshine. UV rays convert an inactive of Vitamin D in our skin to active Vitamin D. However, within the UK, we do not have the right amounts of UV rays all year round, which means deficiency may be more prevalent in the winter. Due to the UK population having their main source of Vitamin D reduced in the winter, there tends to be an increased interest and drive around the winter months for Vitamin D supplementation and fortification. That being said, many of us do not have sufficient time in the sun throughout the summer months, nor do we consume enough in our diet. So, is Vitamin D a focal point of the diet just in winter or all around the year too?
Recommendations state that we require at least 15mins of sunshine exposure on uncovered and unprotected skin in order to gain our daily requirements. This recommendation is provided with a caveat that it must be between April and September, and 11am-3pm in the UK. Of course, reaching these requirements for some people may not always be possible. We have already discussed how time of year affects this, but it should be mentioned that this recommendation is not attainable to people who wear modest clothing or those who are housebound. This is why we are also recommend consuming 400iu or 10mcg of Vitamin D through our daily diet. These values can seem rather arbitrary when it’s not put in the context of food, this is discussed below.
Vitamin D3 in the Diet
Vitamin D rich sources of food include the following:
- Egg Yolks
- Fortified Milk
- Red Meat
For reference, in an average medium egg you will only find 1.6mcg of Vitamin D. Meaning that you would need to eat 6.25 eggs per day. Alternatively, a more potent source of Vitamin D is Salmon, on average 100grams of wild salmon contains 988iu, whereas 100grams of farmed salmon provides 240iu of Vitamin D. Finally, looking at the nutrition information of a popular plant-based milk (Oatly) found that in 100ml of the milk there is 1.1mcg of Vitamin D. Meaning that you would need to drink ~910ml of oatly milk to meet your daily needs.
It’s worth mentioning that Public Health England advised, in 2016, that to protect bone and muscle health, everyone needs a daily vitamin D supplement equivalent to an average daily intake of 10 micrograms. The NHS recommends that an adult should take no more than 4000iu or 100mcg of Vitamin D per day.
So, as you may see above, unless you are an avid consumer of fish you are unlikely to be reaching your daily Vitamin D needs all year around. According to the national diet and nutrition survey (NDNS) there has been a 9-year decline in dietary Vitamin D intake between 2009-2017. Additionally, mean intakes of vitamin D were below the RNI in all age/sex groups.
Without Vitamin D, Calcium is unable to absorb effectively from the intestine and manage calcium homeostasis intra- and extracellularly within physiologically acceptable range. Vitamin D uses the hormonal form 1,25-(OH)2D, which acts through a nuclear vitamin D receptor to enhance the efficiency of intestinal absorption of dietary calcium.
Calcium is needed for effective muscle contraction; without it the action cannot be completed. As we have discussed above, Vitamin D is essential for calcium absorption in order for this to take place. Not to mention that a clinical symptom of vitamin D deficiency include proximal muscle weakness, muscle pain, and gait impairments. A cause-and-effect relationship has been established between the dietary intake of vitamin D and maintenance of normal muscle function.
Bone and Dental Health
Once again using the knowledge that we know above, Vitamin D is essential for calcium absorption. Calcium plays a vital structural role in bones. When Calcium and Vitamin D are taken together, they have been shown to reduce the loss of bone mineral in post-menopausal women. Low bone mineral density is a risk factor for osteoporotic bone fractures. As well as reducing the risk of falls associated with postural instability and muscle weakness. Falling is a risk factor for bone fractures among men and women 60 years of age and older. Not to mention Vitamin D being used for healthy mineralisation of strong teeth.
Time and time again, studies have demonstrated that taking vitamin D supplementation has positive effects on bone strength and mineralisation. One study on post-menopausal women and older men found that supplementing with Vitamin D alongside calcium results in small increases in bone mineral density. In addition, several studies have found a link between low serum Vitamin D and fractures within older adults. Lastly, Calcium and vitamin D supplementation have been associated with a lower risk of tooth loss and better periodontal health in elderly men and women.
Lastly, Vitamin D receptors are found on T-helper 1 and 2 immune cells, indicating that they help to modulate the immune system and inflammatory responses.
Our Vitamin D3 Softgels
In the UK, we have to rely on our diet for adequate intake. This is made easier by a simple 1 a day supplement providing 250% (1000iu) of your daily needs. Vitamin D is responsible for adequate calcium absorption, which in turn contributes to the maintenance of muscle function, teeth and bones. Evidence shows that just 20mcg/800iu can reduce the risk of falling associated with postural instability and muscle weakness. Falling is a risk factor for bone fractures among men and women 60 years of age and older. In addition, adequate Vitamin D3 contributes to the normal function of the immune system. Each pack of Biovit’s Vitamin D3 softgels provides 60 doses, or a 2 months' supply.
So, as you’ll see, Vitamin D3 and its incredible health effects aren’t just essential at winter, but all year around too.