The importance of vitamin D in supporting the immune system

Researchers from The Irish Longitudinal Study on Ageing (TILDA) have released a crucial report which shines a light on the role of vitamin D and unveils shocking levels of deficiency in older people in Ireland. The team, based at Trinity College in Dublin, concluded that Vitamin D supplementation was necessary for those over the age of 50 and those currently shielding. They also highlighted a range of studies showing vitamin D plays a role in the prevention of respiratory infections, boosting the immune system response to infections and reducing the need for antibiotic use. 

The study, titled Vitamin D deficiency in Ireland – implications for COVID-19, used data from wave 1 of The Irish Longitudinal Study on Ageing (TILDA), which started back in 2009. This was a prospective study of 8,172 adults aged 50 years and older in Ireland living in the community – not in care homes or hospitals. The participants were personally interviewed and their answers on their socio-demographic status, physical, mental and behavioural health recorded. 72% of the participants consented to a health assessment and of those, 91% submitted a blood sample for vitamin D level assessment (5,382 people). 

The data revealed that of those aged 55+ years in the Republic of Ireland, 1 in 5 are vitamin D deficient during the winter and 1 in 12 during the summer. This rises to nearly 30% of those aged 70+ and 47% of those aged 85+. These are the age groups considered to be ‘extremely medically vulnerable’ to adverse health outcomes of COVID-19 and have been advised to participate in ‘cocooning’ (known as ‘shielding’ in the UK) during the pandemic.

The researchers also considered the findings of a range of medical studies into the role of Vitamin D in immune function and immune response to infection. One such study in 2017 carried out by Vanherwegen AS, Gysemans C, Mathieu looked at regulation of immune function by vitamin D and its use in diseases of immunity.

Principal Investigator of TILDA Rose Anne Kenny comments:

“We have evidence to support a role for Vitamin D in the prevention of chest infections, particularly in older adults who have low levels. In one study Vitamin D reduced the risk of chest infections to half in people who took supplements. Though we do not know specifically of the role of Vitamin D in COVID infections, given its wider implications for improving immune responses and clear evidence for bone and muscle health, those cocooning and other at-risk cohorts should ensure they have an adequate intake of Vitamin D.”

The researchers concluded that adults aged over 50 should take Vitamin D supplements, and not just in winter, but all year round if they don’t get enough sun.


Altruvita’s high quality Vitamin D supplement is from cholecalciferol and provides around 500% of the adult daily requirement for health.

Can Vitamin D help you right now?

As governments around the world battle the COVID-19 pandemic, public health measures that can reduce the risk of infection and death in addition to lockdowns and social distancing are desperately needed. Here at Altruvita we’re constantly reading about the latest clinical trials and studies looking at the impact of micronutrients, nutrition and vitamin deficiencies on health.

An article published by a team based in the US and Hungary reviewed the roles of vitamin D in reducing the risk of respiratory tract infections, knowledge about the epidemiology of influenza and COVID-19 and how vitamin D supplementation might be a useful measure to reduce risk. 

Vitamin D is already known to reduce risk of infections through several mechanisms. Those mechanisms include lowering viral replication rates and reducing concentrations of pro-inflammatory chemicals that produce the inflammation that injures the lining of the lungs, leading to pneumonia.

Evidence supporting the role of vitamin D blood levels in reducing risk of COVID-19 infection includes that fact that the outbreak occurred in winter, a time when vitamin D concentrations are lowest. Note that the number of cases now in the southern hemisphere near the end of their summer are low (for example in Australia, New Zealand and South Africa). Cases have been higher than in areas which are most likely to have vitamin D deficiency.

Vitamin D deficiency has been found to contribute to acute respiratory distress syndrome (ARDS); and that case-fatality rates increase with age and with chronic disease comorbidity, both of which are associated with lower 25(OH)D concentration. 

According to national surveys in the UK, across the population approximately 1 in 5 people are thought to have low vitamin D levels and are deficient (defined as serum levels below 25 nmol/L). Patients with levels 25 nmol/L to 50 nmol/L are classed as insufficient.

The UK has been lucky to enjoy sunny weather since the start of the lockdown, an end to the heavy rain of the winter just gone. Those of us who are lucky enough to be able to get out in our gardens or take a daily walk outside are now getting an opportunity to soak up some sunshine. Between late March/early April and September, the majority of people aged 5 years and above will probably obtain sufficient vitamin D from sunlight when they are outdoors, alongside foods that naturally contain or are fortified with vitamin D.

However, the authors of the review suggest that the goal should be to raise 25(OH)D concentrations above 100-150 nmol/L, which is way higher than just obtaining sufficient levels (anything over 50 nmol/L). The only way to achieve this fast enough during the peak of the this pandemic is to do everything – get out in the sun, eat vitamin D rich foods and take a supplement.

Some studies have reported that vitamin D supplementation reduced the risk of influenza, whereas others studies did not. To reduce the risk of infection, the authors of this paper advised that people at risk of influenza and/or COVID-19 consider taking 10,000 IU/d of vitamin D3 for a few weeks to rapidly raise 25(OH)D concentrations, followed by 5000 IU/d. For treatment of people who become infected with COVID-19, higher vitamin D3 doses might be useful. Randomised controlled trials and large population studies should be conducted to evaluate these recommendations.

Vitamin D supports the immune system.* Explore Altruvita’s Vitamin D supplement and the rest of our Immune Support range – just click hereOur Vitamin D is from cholecalciferol and provides around 500% of the adult daily requirement for health.

* EU REGISTERS ON NUTRITION AND HEALTH CLAIMS

Reference:

Grant WB, Lahore H, McDonnell SL et al. Evidence that Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths. Nutrients. 2020 Apr 2;12(4). pii: E988. doi: 10.3390/nu12040988.

Why is Vitamin D so important for our health?

sunlight

At a time when it’s crucial to have a healthy immune system, both to help prevent infections and support our body in recovering when we do get ill, we wanted to share some facts and important information with you about vitamin D. 

How do our bodies get vitamin D?

In humans, around 90% of the vitamin D we need is synthesised in the skin when we are exposed to sunlight and the other 10% is obtained from certain foods. The former is why it is sometimes referred to as the ‘sunshine vitamin’! The amount of vitamin D that we produce is influenced by the latitude we live at, the time of year it is, the time of day we tend to venture outside, whether we are wearing sunscreen and the natural pigmentation of our skin. 

For example, during the winter months in the UK (and anywhere else above the northerly latitude of 35 degrees) the UVB rays from the sun don’t penetrate all the way down to our skin, so we can’t make vitamin D. That’s why Public Health England recommends that all adults and children (over the age of 1) should take a vitamin D supplement throughout autumn and winter.

Why is vitamin D so important?

When our bodies get vitamin D (from either the skin’s exposure to sunlight or food) they turn it into a hormone called activated vitamin D or calciferol. This works to help to regulate the amount of calcium and phosphorus in our bodies for healthy bones, muscles and teeth. 

Did you know that even if you get plenty of calcium in your diet (from sources such as milk and leafy green vegetables), your body can’t absorb it unless you have enough vitamin D?  That means that a lack of vitamin D can lead to bone deformities such as rickets in children, and a bone condition called osteomalacia in adults. 

Activated vitamin D also contributes to the normal function of the immune system and the process of cell division. If you are keen to support your immune system function at this time, it’s worth considering if you are likely to be getting enough vitamin D. 

Who is at risk of vitamin D deficiency?

  • People who are unable to go out much during the daytime in those all-important spring and summer months, such as office workers, the housebound, and night shift or factory workers. 
  • People who cover most of their skin with clothing when they go outside, even during the warmer weather.
  • People over 65, because their skin is not as good at making vitamin D. 
  • Now that self-isolation and social distancing measures are part of our day-to-day life, we all need to keep an eye on the amount of sunlight we get.   

Which foods can we get Vitamin D from?

As mentioned above, the best source of vitamin D is when our bodies are exposed to sunlight and make it for us, but we can get a small amount by eating certain foods as well. 

The most common food sources of vitamin D include: 

  • Oily fish such as sardines, salmon, pilchards, trout, herring and kippers.
  • Eggs – mainly from the yolk, so be careful if you’re keen on egg white omelette! 
  • Red meat, though this will vary depending on what kind of meat and the time of year it is produced. 
  • Milk – again, it can depend on the time of year
  • Fortified products such as cereals, some dairy products and soy milk.

Altruvita’s high-strength vitamin D supplement

Along with vitamin C and selenium, vitamin D helps to support a healthy immune system, along with the other important roles it plays in our body. Shop Altruvita’s high-quality cholecalciferol vitamin D supplement here

A startling fact about British wintertime and vitamin D…

Do you feel a little gloomy and run down in the winter? It might interest you to know that the lack of sunshine during those colder months of the year doesn’t just impact our mood, it actually can impact on our physical health too. Direct sunlight acting on the skin provides the majority of our vitamin D requirement, so when there’s less sun, we make less of this essential nutrient.  

The link between certain health problems and a Vitamin D deficiency has been noted through comparisons between regions with relatively low levels of sunlight, and those that enjoy more hours of sunshine. Incidence of various cancers, irritable bowel syndrome and inflammatory bowel disease have all been linked to low exposure to sunlight and a reduction in the potential of vitamin D production.

You might be deficient in vitamin D if you cover your skin, or if you spend the daylight hours indoors. For individuals living above the north latitude of 35 degrees (which is all of the United Kingdom!), the sun cannot not reach the necessary angle for UVB penetration for all of the winter months. That means that for UK residents there is no opportunity for winter vitamin D production, unless you head to warmer climes for a holiday! 

Vitamin D levels are also strongly linked to mental illness, with a Swedish study showing 58 percent of people who had attempted suicide were vitamin D deficient. They concluded that testing vitamin D levels in mental health care is of vital importance.

Thankfully, vitamin D can also be consumed through dietary sources! There are certain foods that are very rich in vitamin D. Oily fish such as mackerel, salmon and tuna are not only excellent sources of vitamin D, they also contain omega-3 fats that deliver benefits to the cardiovascular system. Among the other foods that can boost your daily vitamin D intake are fortified milk, mushrooms, egg yolks, liver and fortified breakfast cereals. 

Sunlight is our main provider of vitamin D, so over the winter months especially, vitamin D supplementation is recommended for adults and children in the UK.

Photo by Diana Parkhouse on Unsplash