As we age, our immune system becomes less effective at fighting infections and less responsive to vaccinations. The ageing immune system is associated with chronic inflammation which in turn is linked to just about every condition linked to old age.
However, making eating a healthy diet and exercising regularly a part of your life can help you maintain a healthy immune system into old age.
Since the 18th century our average lifespan has doubled due to improvements in healthcare and sanitation. However, unless you remain healthy, mobile and socially engaged in those latter years is the increase in years lived really worth it?
The immune system has two branches- innate and adaptive. The innate system is more basic and you were born with it. It is nonspecific and reacts to all foreign threats to the body. Adaptive immunity is ‘learnt’ and reacts when it encounters a bacteria, virus or fungi that it remembers from a previous infection and to which it has developed an appropriate antigen.
As we age, innate immunity can become over stimulated and the initial immune reaction (inflammation) does not settle down after a short period but becomes ongoing or ‘chronic’. At the same time, the adaptive immune system becomes less effective at fighting infection.
The types of disease which we see associated with a state of chronic inflammation include cancer, type 2 diabetes, cardiovascular disease and dementia. It is also a core feature of certain autoimmune conditions which are common in older people such as rheumatoid arthritis.
The key message here is that keeping your immune system healthy and avoiding chronic inflammation are important aspects of staying well into old age.
How to do that?
Physical exercise- several studies have demonstrated that regular exercise seems to keep immune cells ‘younger’ longer. In one study 61 healthy men, aged 65-85 years were given a flu shot and their immune response recorded. Those that were moderately active and very active produced more antibodies in response to the vaccine than the mostly inactive men. The response was greater the more exercise they did.
We should note that this was not a controlled trial so there may have been other aspects of their lifestyles which contributed to their better immune response too.
Which brings us to diet…There is no direct evidence that a particular diet can slow down immune ageing. But there are plenty of associations. In particular, research suggests that diet is linked to older people’s risk of developing sarcopenia. This condition causes a loss of muscle mass, strength, and functionality.
It seems to be that there is a two-way relationship between skeletal muscle and the immune system. Muscles produce anti-inflammatory chemicals called myokines, which downgrade chronic inflammation but research also suggests that chronic inflammation can accelerate muscle loss in sarcopenia. So, both exercise to rebuild and maintain muscle and protein and vitamin D adequacy to support that muscle building are important, but so are anti-inflammatory foods to reduce the inflammation.
The Mediterranean diet is an excellent example of a diet pattern which is high in antioxidants and low in inflammatory foods such as processed, fried, overly salty and sugary foods and red meat. In countries where this kind of eating prevails we see people living an active and healthy life well into their nineties and beyond. Typically, they also enjoy many social occasions around food and family and stay actively involved in walking, gardening, farming and so on. Read my blogpost on the Mediterranean diet here: And on living longer here.
As we age it’s not unusual to put on a bit of weight. Fat or adipose tissue that accumulates around the middle and the organs is particularly associated with cytokine release (chemicals which can lead to chronic inflammation). Therefore maintaining a moderate weight is important. Slightly heavier than is recommended for people under age 70 is fine, as studies have shown that older adults with lower body mass don’t recover as well after an illness, but a ‘beer gut’ or ‘spare tyre’ is definitely not a good thing for our immune system or just about anything else!
Interested in knowing more? My upcoming six week course “Healthy Ageing”, run in conjunction with Pilates and Fitness instructor Charmaine Voigt brings you all you need to know and all the tools you need to address eating well and exercising to maintain your fitness inside and out for the years ahead. Check it out here: https://www.goodnessmenutrition.com.au/healthy-ageing-course and register early to get the Early Bird Special price of $145.