It’s not uncommon to feel run down or susceptible to the odd cold or bout of flu during winter, but if you find yourself more vulnerable than usual or taking longer to bounce back, your lifestyle could be putting strain on your immune system. Addressing a few of these factors might just help to get your health back on track…
Get more fresh air
Many of us spend our daytimes indoors, in spaces with poor ventilation or air-conditioning – this can promote the airborne transmission of viruses such as the rhinovirus, which is responsible for around 40% of colds. If your working environment makes this unavoidable, or if you have a long and stuffy commute to work, it’s all the more important to get outdoors to strengthen your immune system. Try nipping out for a stroll at lunchtime, or regular weekend walks with friends and family.
The sunshine vitamin
Yes, you guessed it – vitamin D. Insufficient daylight exposure limits our ability to produce this immune-supporting micronutrient. Altered levels of vitamin D3, the active metabolite of vitamin D, have been associated with a higher susceptibility to immune-mediated disorders and inflammatory diseases. This is because vitamin D3 is crucial for activating our immune defences and, in particular, stimulating the cells that are involved in detecting and killing off the bacteria and viruses that have the potential to make us ill.
Vitamin D has the ability to transform immune cells – primarily T-cells and macrophages – from inactive and harmless immune cells into killer cells that are able to react to and fight off serious infections in the body by seeking out pathogens and destroying them.
According to scientific studies, we can get sufficient levels of vitamin D with as little as 15-30 minutes of sun exposure. When it’s cold though, most of us cover up to keep warm, and getting enough natural sunlight can prove especially difficult for those living in built-up areas. No need to fret, though, as vitamin D can also be sourced from the diet. The recommended daily allowance (RDA) for adults for adults is 5 mcg or 200 IU, easily achieved by regularly incorporating oily fish, eggs, cheese or milk (or soya milk for vegans) into the diet.
Don’t stress yourself sick
A major influence on the immune system’s ability to defend against bacterial and viral infections is stress. Stress presents itself in many forms; whether it’s induced by sleep deprivation, physical exertion, poor diet, emotional pressure, work pressure – you name it, most of us are exposed to stress in one form or another.
Elevated stress levels increase the production of hormones such as cortisol and adrenaline – a natural and necessary response if you find yourself in life-threatening circumstances and need to defend yourself against – or run from – harm. Chronic elevated levels of cortisol can lead to exhaustion, however, directly compromising the immune system by preventing the proliferation of T-cells and macrophages, and therefore reducing the amount of immune cells available to combat infection.
Managing stress is therefore essential for our wellbeing – not only to help us cope better with everyday pressures, but also so we’re better equipped to fight pathogens and save our immune defences for when we really need them. Whilst we can’t always change what’s creating our stress, we can – gradually – learn how to cope better with life’s daily challenges. Introducing regular moderate exercise, or practicing yoga and mindful meditation may bring some calm into your life, helping to regulate the production of stress hormones, while also increasing the production of the mood-regulating neurotransmitter serotonin.
Exercise can also help to increase our immune defences, but it’s all about balance as we found out in a recent interview with body fitness champion and personal trainer Karen Norris about the relationship between exercise and immunity.