Question: Why can some people’s immune system be stronger and some weaker?

Helena Fisk answered on 12 May 2020:

Hi Mellisa, great question!
There are a number of things that can influence our immune response / how strong our immune system is. Our genetics, race, sex, lifestyle (diet and exercise) and age can all affect our immune system. I’ve given a bit of detail for each below 🙂

Our genetics can influence our immune system and immune system disorders can be inherited from our parents. In this way people may be born with or develop immunodeficiency disorders (weakened immune system so we are unable to defend ourselves against viruses and bacteria) or autoimmune disorders (where the immune system mistakenly attacks our body).

Response to vaccination and how common particular diseases are in a population has been seen to differ by race and sex. For example, females and African American, American Indian, or Latino individuals have a higher risk of developing autoimmune diseases.

Our immune system naturally declines with age so response to vaccination is lowered in the elderly and susceptibility to infection increases.

Our lifestyle can also influence our immune system. Eating a healthy well balanced diet including foods rich in B vitamins, vitamin C, vitamin D, omega-3 fats, and fibre (which is good for our good gut bacteria which have an impact on our immune system) can help support our immune system. Exercise has also been shown to help support our immune system.
Here is a link to NHS and British dietetic association resources that give more info on nutrients and what foods are good sources of these:
https://www.nhs.uk/conditions/vitamins-and-minerals/
https://www.bda.uk.com/food-health/food-facts/nutrients-food-facts.html

I hope that was helpful and not too much info! 🙂