Could playing host to parasitic worms help healthy ageing?

Parasitic worms could hold the key to living longer and free of chronic disease, according to a review of prior evidence written by UCL researchers. The review, published in  eLife , looks at the growing evidence to suggest that losing our 'old friend' helminths (parasitic worms), which used to live relatively harmlessly in our bodies, can cause ageing-associated inflammation. The researchers raise the possibility that carefully controlled, restorative helminth treatments could prevent ageing and protect against diseases such as heart disease and dementia, and warrant further investigation. Bruce Zhang, BSc student with the UCL Institute of Healthy Ageing and co-author of the review, said: "A decline in exposure to commensal microbes and gut helminths in developed countries has been linked to increased prevalence of allergic and autoimmune inflammatory disorders - the so-called 'old friends hypothesis'. "A further possibility is that this loss of 'old friend' microbes and helminths increases the sterile, ageing-associated inflammation known as inflammageing." Inflammageing is increasingly thought to be a contributory factor to the major diseases of later life, including heart disease, dementia, cancer, chronic obstructive pulmonary disease, osteoporosis, age-related eye disease and - more recently - symptom severity during SARS-CoV-2 (COVID-19) infections. One theory is that changes in the gut microbiome might cause inflammageing, but until now little consideration has been given to the role of organisms comprising the macrobiome - the ecosystem of macro-organisms - including helminth parasites such as flukes, tapeworms and nematodes.