Whilst we are in the midst of the coronavirus Covid-19 crisis, there has never been a more important time to keep your immune system fit and healthy.

The immune system is our bodies defence against invading bacteria, viruses, fungi, parasites and other pathogens. It is a complex network of hundreds of specialised cell types and organs and is the second most complicated structure in the body, after the brain.

Specialised cells called neutrophils, macrophages, lymphocytes and other white blood cells travel around the body and using molecular recognition, identify foreign invaders and destroy them. A recent article in New Scientist (28th March 2020), says you`re only as young as your immune system.

At around the age of 60, the immune system deteriorates, a process called immunosenescence. The immune cells become less mobile and efficient, which over time make us more susceptible to disease and illness .However, the good news is that you can do a lot to reverse this process with lifestyle changes. A recent study by Lord et al (2018), found that a group of cyclists aged between 55-79 years of age (who exercised regularly), had immune systems that were biologically 20 years younger.

Research has shown that there are many factors that influence the efficiency of our immune system. Adequate sleep is vitally important. Deprivation leads to reduced antibody production and raised levels of stress hormones such as cortisol (which dampen the immune response). Melatonin a hormone involved in sleep, also helps reduce inflammation, which if excessive, is detrimental to immune function.

Exercise, as mentioned earlier, is a key factor in keeping the immune system healthy. Clinical trials have shown that regular exercise boosts the activity and efficiency of your immune cells. In fact being active and using your muscles stimulates macrophages and results in an anti-inflammatory response. Blomberg (2015), showed that obesity and sedentary life resulted in greater levels of adipose (fat) tissue, producing a negative effect on the immune system. Exercise can be many things ranging from cleaning the house to long walks and running. Keeping active is the key.

Science has also shown how vital nutrition is to our immune function. Most people know that a well-balanced diet of animal and vegetable protein, combined with fruit and vegetables is important. However, there are additional vitamins and minerals which have been shown to help boost the immune system. Professor Dayong Wu et al (2018), has demonstrated in clinical trials that vitamins vitamin D + E are associated with improved immune function. Foods particularly high in vitamin D are tuna, mackerel, salmon, cheese and egg yolk. While vitamin E levels are higher in avocado, spinach, almonds and other nuts. The mineral Zinc has also been shown to improve immune function, but it is important not to exceed 30 mg /day.

There is particular interest in how our gut bacteria are involved in health and it is thought they too have a role in the immune systems health. Probiotics and fermented foods, such as kimchi and a diet high in fibre, is also recommended.

There is a lot of interest currently in how restricting food intake improves immune function. Our evolutionary adaptation to starvation is that it prioritises our repair and immune cells over others, such as those involved in growth and reproduction. Diets, such as the immune diet are gaining interest as a way of boosting health and well-being. They appear to work by deactivating a nutrient sensing pathway inside cells called mTOR which appears to boost the immune system. Although research is on-going, the 16:8 diet is showing promising results. This involves having no calories for 16 hours and then eating during an 8 hour period. This can be done either once a week or for longer periods. The drug Rapamycin appears to produce the same effect and is currently undergoing trials. Statins, the cholesterol lowering drug has also shown similar results, but research is at an early stage. Another area of huge importance is mental well-being. This has been discussed in detail in this article by Anna Tingle, one of our clinic psychotherapists.

In summary, the best and most effective way of keeping your immune system fit and healthy is the following:

  • Adequate sleep
  • Regular exercise
  • A well-balanced diet
  • Vitamins D+E
  • Zinc (with other minerals)
  • Probiotics
  • Fasting diets
  • Mental well-being and stress management
  • Don’t smoke
  • If you drink alcohol, drink in moderation

Clive D Lathey D.O MSc (Sports Medicine)

Registered Osteopath, Sports Scientist + Clinic Director