Retirement Life
18 January 2023

The secrets for improved immunity in older age

As we grow older, our immune systems tend to weaken, making us more susceptible to illnesses and infections. This is due to a variety of factors, such as a decrease in the production of immune cells, lower levels of antibodies and a decrease in the body’s ability to fight off disease. While there is no way to completely stop the ageing process, there are steps that can be taken to help maintain a healthy immune system as we age.


To begin with, it is important to consider our sleep levels. As we age, our bodies need more rest, and not getting enough sleep can have a negative effect on the immune system. A 2015 study from the University of California showed that people who slept fewer than six hours each night during the course of a week were more than 4.2 times more likely to catch a cold. However, it should be noted that the researchers deliberately tried to infect the participants by directly administering nasal drops containing the cold virus. As a general rule, aim for seven to eight hours of uninterrupted sleep every night.


A balanced diet is also crucial for a healthy immune system, with plenty of fruits and vegetables containing essential vitamins and minerals. Limiting processed and sugary foods can also prevent the weakening of the immune system. For some people as they age, a loss of interest in food makes it harder to eat well and get all the nutrients we need for good health. Reducing calorie intake may also help to extend your lifespan, according to various studies.


As Sara Stanner, Science Director at the British Nutrition Foundation, says, “There’s no single nutrient or food that can ‘boost’ immunity. This means that having a healthy, varied diet is key for getting the nutrients that are most important for our immune system, as well as all the other systems of the body.”

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Exercise is probably one of the most crucial things we can do to maintain a healthy immune system. Professor Janet Lord, director of the Institute of Inflammation and Ageing at the University of Birmingham in the UK, says,

The immune system declines by about two to three percent a year from our 20s

, which explains why older people are more susceptible to infections, conditions like rheumatoid arthritis and, potentially, cancer. The thymus, a specialised organ of the immune system, declines in output with age. As a 70-year-old, you only have about one to five percent of the thymus output that you had as a 20-year-old.


Janet’s research looked at how exercise can prevent the immune system from declining and instead protect people against infections. The study found that of the 125 endurance cyclists they studied (aged between 55-79), most of them were producing the same level of T-cells as adults in their 20s, whereas a group of inactive older adults were producing very few.

The group also didn’t put on weight as they aged, and their metabolic health was maintained. Also, the thymic output did not decline in this group of cyclists.


Although exercising doesn’t protect against every aspect of ageing, it’s a way of maintaining a healthy age for longer. In summary, lifelong physical activity protects against some aspects of ageing, but not all.


And finally, it is vital to reduce the amount of stress in your life. Stress can have a negative effect on the immune system, making us more prone to illness and infection. A 2008 study showed that short-term stress boosted the immune system, but chronic stress has a significant effect on the immune system that ultimately manifests in an illness, due to a suppression of the immune system.


Taking time for yourself to relax and unwind can help to reduce stress and keep the immune system healthy. 

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Simple steps, regularly reinforced, can reduce our risks of illnesses and infections, allowing us to live a healthier and more productive life.


This article is for informational purposes only and should not be considered financial or medical advice.

Photo of Kathy Catton
Written by:

Kathy Catton

Kathy Catton is a freelance writer and editor, based on the Banks Peninsula. She is an experienced feature writer, magazine editor and copywriter. Quick to grasp the crux of any story and tell it in plain English, Kathy enjoys bringing stories to readers that surprise and delight.

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