Great blog post answering this vexing question from Biocare the other day. I’ve added it – and my comments as usual – to the COVID-19 Guidance document which you can always find here.
Why are older people at more risk?
An age-related decline in immune function is one of the most recognised consequences of ageing.[iii] This age-related change is driven by reduced production of white blood cells, free radical damage, and increased inflammation.[iv] The immune system of older individuals is therefore prone to mounting a weaker response to ‘threats’ such as bacteria and viruses than that of younger individuals.
It is common for older individuals to have one or more health conditions which can compromise their immune system further. A health survey published in 2018 reported that 33% of women and 42% of men aged 75 and over were living with cardiovascular disease,[v] whereas the prevalence was around 5% for both genders aged 16-34 years.
[Ed: In fact, only today I saw figures from a study in Wuhan where they found most people who died from COVID-19 were over 50, male and had at least one chronic illness, the top ones being high blood pressure, cardiovascular disease and diabetes – if that describes you, it is even more important you take more care of yourself using the info below and from your doctors, please. That’s not to say you’re even going to get the virus and you might have it mildly or not even know you’ve got it; just that having one or more chronic conditions makes the severity risk higher. Knowledge is power. I do also wonder if it is the meds people are taking for these things that might also be causing some problems, which brings us neatly onto the next point Biocare made…]
Use of multiple medications is prevalent amongst the older population. 1 in 10 people aged 65 and over take at least 8 different prescribed medications a week, with this increasing to 1 in 4 of those aged 85 and over.[vi] But did you know that certain medications can actively deplete nutrients? For example, proton pump inhibitors (PPIs) and non-steroidal anti-inflammatory drugs (NSAIDs) can deplete iron and vitamin C, blood pressure medications (e.g. diuretics, beta blockers) can deplete zinc, and bronchodilators and statins can deplete vitamin D.[vii] Commonly prescribed medications can therefore reduce an individual’s level of the very nutrients required for a strong immune system! For those on multiple medications, we encourage them to contact us, the Clinical Nutrition team, so we can advise them about which nutrients they might need to increase their intake of. [Ed: or ask me :)]
Dehydration is common amongst older individuals. Some dislike the taste of water, while others opt for a cup of tea instead, not realising that tea and coffee are ultimately dehydrating due to the caffeine. [Ed: I’m not sure that’s true anymore actually, but….] There is even a suggestion that older individuals may be less likely to experience thirst and more likely to drink less as a consequence.[viii] Dehydration can impair blood flow and cellular activity which might then compromise immunity. It is also a risk factor for urinary tract infections (UTIs) and poor kidney health,[ix] which can put further strain on the immune system.
Poor digestion – as we get older, stomach acid production tends to decline by 30-40% which can compromise our ability to digest and absorb nutrients efficiently from food.[x] This can make us more prone to nutrient depletion, which can then compromise the health of the immune system and beyond. Many medications also directly impact our gut microbiome, such as antibiotics[xi] and PPIs,[xii] further compromising our digestive and immune system. [Ed: see more on low stomach acid and enzymes here.]
Poor digestion coupled with other factors such as low dietary diversity and use of multiple medications, is likely putting older individuals at risk of nutrient deficiencies/insufficiencies which are weakening their immune system, including:
Zinc supports the function of white blood cells and low levels impair immunity.[xiii],[xiv],[xv]Zinc deficiency may increase the risk of pneumonia amongst older individuals.[xvi]
Vitamin A supports multiple aspects of the immune response.[xvii],[xviii] Deficiency is associated with an increased risk of infection.[xix]
Vitamin D supports bone health,[xx] immune function,[xxi] and mental health[xxii] to name just a few functions. Up to 50% of adults aged 65 and over in the UK are deficient in vitamin D though![xxiii] Vitamin D has specifically been shown to help prevent and manage the symptoms of viral infections in older individuals.[xxiv]
Iron is vital to healthy oxygen transport around the body.[xxv] Iron deficiency therefore limits oxygen delivery to cells, driving fatigue and decreased immunity.[xxvi],[xxvii]
In the document, I have also added supplement and dosage suggestions for you to help with those. You can find the full COVID-19 Guidance document here.