Food & Nutrition

Your Winter Immune Health Toolkit – Are You Vitamin D Deficient?

Eloise Edington  |   12 Nov 2021

This year, more than ever, immune health is at the forefront of our minds, and especially from the perspective of ‘what can I do to help myself?’  The good news is, there’s lots you can do. And a great place to start is to build a winter immune health toolkit. 

Today on Fertility Help Hub, leaders in the supplement / wellbeing field, Nutri Advanced, share how to build your winter toolkit.

By Rachel Bartholomew BA (Hons), Dip ION, mBANT, CNHC, GHW – Nutritionist & Health Writer at Nutri Advanced

Amid the busy-ness of life however, the last thing you need, especially at this time of year is another long to do list.  Trying to do too much at once often leads to overwhelm and inaction, and that’s no help to anyone.

Have you been googling, “Vitamin D deficiency for fertility”?

Simply start at the top of the table below and work your way down at your own pace. Your immune system will thank you for it.

“So this little toolkit has been put together with gentle ease and simplicity in mind, because we could all do with a bit more of that.”

Your Winter Immune Health Toolkit 

Vitamin or nutrient, where it is sources and the supplemented form:

  • Vitamin D – can be sourced from sunlight, mushrooms, wild oily fish, egg yolks and fortified foods. The supplemented form is Vitamin D3
  • Vitamin K – can be sourced from fermented foods such as cheese and natto. The supplemented from is Vitamin K2 (MK-7)
  • Vitamin C – can be sourced from citrus fruits, bell peppers, kiwi fruit, broccoli, papaya, Brussels sprouts, cantaloupe melon and berries. The supplemented form is ascorbic acid.
  • Quercetin – can be sourced from onions, apples, berries, broccoli, kale and some teas. The supplemented form os Quercetin 
  • Zinc – can be sourced from lamb, pumpkin seeds, hemp seeds, grass-fed beef, chickpeas, lentils and cacao. The supplemented form is zinc bisglycinate
  • Selenium – can be sourced from brazil nuts, eggs, liver, poultry and sunflower seeds. The supplemented form is selenomethionine

1. Vitamin D3 (& K2)

It’s no accident that the powerful partnership of Vitamin D3 & Vitamin K2 is top of your toolkit list. In fact, maintaining optimal Vitamin D levels is likely the single-most important step you can take to support your immune system right now. Often referred to as the ‘sunshine’ vitamin, Vitamin D supports immune function and maintaining healthy levels is vital for supporting your body’s ability to fight infection.

In fact, it has recently been studied for its ability to reduce the risk of respiratory infections. Unlike most essential nutrients however, the main source of vitamin D isn’t food, but sunshine. Your bare skin produces Vitamin D when it comes into contact with the sun’s rays, so deficiency risk is increased during the winter months and when spending prolonged time indoors. 

Public health advice is that everyone should take a daily Vitamin D supplement between October – March when there is reduced likelihood of Vitamin D production in the skin. Exceptions are babies receiving 500ml or more fortified formula milk daily, or breastfed babies where mum is certain that her breast milk contains optimal daily amounts. Getting enough Vitamin D via breast milk is a challenge however and for most breastfed babies, a daily supplement will be required.

Vitamin K is the icing on the cake where Vitamin D supplementation is concerned and yet not many people realise how closely these two nutrients work together to support immune, bone, and heart health. In one study, researchers found Vitamin K was reduced in patients with Covid-19 and was related to poor prognosis. Whilst further research is now needed to evaluate whether Vitamin K supplementation improves outcomes in Covid-19, it is already suggested that vitamins D & K work well when taken together. Vitamin K is ideally supplemented as K2 in the form of MK-7, a special form which is generally agreed to be one of the most effective ways to supplement Vitamin K.

2. Vitamin C

Vitamin C comes a close second in your immune health toolkit. This incredible nutrient supports your ability to fight infection, is a powerful antioxidant and has anti-inflammatory activity. It has been shown to shorten the duration of the common cold, prevent it in some conditions and clinical trials are even currently underway to test the effectiveness of Vitamin C in patients with Covid-19. Our bodies can’t make Vitamin C and we have only a very limited capacity to store it, so it must be regularly included in our diets.

Vitamin C is found in fresh fruits and vegetables, yet sadly, intakes are known to be generally low in a typical Western diet high in refined and processed foods. In addition, there are times when our needs for Vitamin C increase significantly, such as when we are fighting infection, and during times of stress and illness. 

This is when our daily intake needs to be increased even further.  In fact, evidence suggests that Vitamin C levels decline dramatically in critically ill patients.  For general health and wellness, and prevention of infection it is important to achieve dietary intakes that provide at least 100 – 200mg per day. In contrast however, when Vitamin C needs increase such as during illness or infection, significantly higher (gram) doses may be needed to compensate for the increased demand.

Good food sources of Vitamin C include citrus fruits, bell peppers, kiwi fruit, broccoli, papaya, Brussels sprouts, cantaloupe melon and berries. Think ‘fresh’, ‘little’ and ‘often’ when adding Vitamin C foods to your diet.  ‘Fresh’ – because the Vitamin C content of foods degrades quickly over time, so the longer you leave fresh fruits and vegetables before eating, the less Vitamin C they will contain.  And ‘little’ and ‘often’ because Vitamin C is processed fairly quickly in the body. 

This means you’ll get more benefit from spreading your Vitamin C foods throughout the day rather than eating lots in one go.  The same is true for Vitamin C supplements too, which are best taken in smaller doses throughout the day or as a time-release formula.  Ascorbic acid is the form of Vitamin C found naturally in food and is often the preferred form in supplements.

3. Quercetin

Quercetin is a flavonoid – a naturally occurring beneficial compound found in plant foods. Flavonoids may be helpful in the protection against disease and several studies have found quercetin to be a useful immune support.

Flavonoids have demonstrated impressive anti-viral, anti-microbial, anti-inflammatory and antioxidant properties and are considered to be a highly valuable addition to the diet. Quercetin may even help to enhance the anti-viral activity of zinc. Quercetin is found in rich supply in onions, apples, berries, kale, broccoli and some teas and can also be taken in supplement form.

For 20% off any Nutri Advanced supplements, use code FHH20 at checkout.

4. Zinc

Zinc is an essential mineral which we need to consume in our diets. A severe deficiency of zinc is known to suppress immune function, and even mild to moderate zinc deficiency can have a negative impact on the immune system’s ability to deal with infection.

The body doesn’t have much ability to store zinc so it’s crucial that your diet consistently delivers this immune-supporting mineral.

Zinc-rich foods include lamb, pumpkin seeds, hemp seeds, grass-fed beef, chickpeas, lentils and cacao.  Plant-based zinc foods are generally less bioavailable than animal sources so those following a vegetarian or vegan diet need to be particularly mindful of getting enough in the diet.  Zinc can be safely taken in the supplement form of zinc bisglycinate.

5. Selenium

Less well known for its impact on immune health, but still a valuable addition to your toolkit, last but not least is selenium, an essential mineral that must be consumed in the diet.  Selenium deficiency seems to speed up the rate that viruses can mutate, and influenza has been found to be more harmful when selenium is deficient. For general immune health, it’s important to ensure that selenium levels are optimal.  Selenium is found in rich supply in Brazil nuts, eggs, liver, poultry and sunflower seeds.  If you need extra selenium in supplement form, this can be taken in the form of selenomethionine.

Nourish your immune system with the ingredients it needs most

Your immune system is incredibly complex, intelligent and effective at protecting you against foreign invaders such as bacteria and viruses.  The aim of your immune health toolkit is to help you to feed and nourish it with the ingredients it needs most to function at its optimal best.  Start with Vitamin D, work your way through at your own pace and know that every little thing you do is worthwhile.

For 20% off any Nutri Advanced supplements, use code FHH20 at checkout.

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