how our immune system changes over time.

How Does Our Immune System Change Through the Years?

Introduction

Our immune system is crucial in protecting us from harmful bacteria, viruses, and other threats. Like the rest of our body, it changes as we age, affecting how well we can fight off illness. From infancy to old age, our immune system evolves, making us more or less vulnerable to certain diseases.

The Science of Immunity and How It Changes with Age

In infancy, babies rely on antibodies passed from their mothers to protect them. Over time, exposure to different environments, foods, and microbes helps build the immune system's ability to fight future infections. During childhood, the immune system continues to grow. By adolescence, it performs at its peak, responding quickly to illness. As we age, lifestyle factors - such as diet, stress, and sleep - affect our immune health. In later years, the immune system gradually weakens, making us more prone to infections. This is known as immunosenescence, where the immune system becomes slower and less effective (Simon et al., 2015).

Supporting Healthy Immunity Through the Years

In infancy, breastfeeding is essential for developing a strong immune system, as it provides important nutrients and immune-boosting antibodies. In adolescence, a balanced diet, exercise, and stress management are key to supporting immunity. In adulthood, lifestyle choices - such as maintaining gut health through diet, probiotics, and regular exercise - play a larger role in immune function. As we age, keeping nutrient levels high, especially vitamin D, zinc, and probiotics, becomes more important to counteract immunosenescence (Simon et al., 2015).

The Gut-Immune Connection: How Probiotics Support Immune Function 

Around 80% of our immune system is in our gut, making gut health essential for strong immunity. The balance of friendly bacteria in the gut helps regulate immune responses. As we age, the types of bacteria in our gut change. Children have more of the Bifidus strains, while adults benefit more from Lactobacillus strains. A study of 106 adults found that synbiotic supplementation improved immune markers and gut bacteria composition (Li et al., 2023). A diet rich in fibre, fermented foods, and probiotics helps maintain a good microbiome balance, supporting immune health and reducing the risk of illness (Simon et al., 2015).

Conclusion

Our immune system changes through life, but we can strengthen it at every stage. Supporting gut health with diet, probiotics, and stress management helps maintain a strong immune system. By understanding how our immunity evolves, we can make choices that keep it healthy and resilient.

References

• Li, X., Hu, S., Yin, J., Peng, X., King, L., Li, L., Xu, Z., Zhou, L., Peng, Z., Ze, X., Zhang, X., Hou, Q., Shan, Z., & Liu, L. (2023). Effect of synbiotic supplementation on immune parameters and gut microbiota in healthy adults: A double-blind randomized controlled trial. Gut Microbes, 15(2), 2247025. https://doi.org/10.1080/19490976.2023.2247025
• Simon, A. K., Hollander, G. A., & McMichael, A. (2015). Evolution of the immune system in humans from infancy to old age. Proceedings of the Royal Society B: Biological Sciences, 282(1821), 20143085. https://doi.org/10.1098/rspb.2014.3085