drplsmith

Thanks for the question, some foods such as smoked or processed meat are linked to an increased risk of cancer. Some pathogens such as Epstein Barr Virus or Helicobacter Pylori are also linked to the aetiology of specific cancers. There can also be heritable factors (gene alleles) that increase the likelihood of cancer. It can be difficult to measure the relative impact of environmental and genetic factors that result in the onset of a given cancer.

Thanks for your comment. Sorry for the loss of your mum.

Generally for Melanoma some patients 'respond' to treatment and some currently do not (this is referred to as primary resistance). This could be for a number of reasons. For those who respond, some do so for many years without the re-emergence of tumours but some patients develop what's referred to as acquired resistance. There are a few reasons for this acquired resistance but ultimately the tumour evolves to escape or inhibit the immune response generated through immunotherapy. This is being intensively studied in order to improve both the number of people who can benefit and prevent the onset of resistance. As an immunologist studying cancer immunotherapy I'm pleased for you that it was at least partially helpful for your mum and am optimistic and determined that improvements to immunotherapy will continue to be made in the years ahead.

The ICVI is a charity that funds my research, and other immunologists, specifically in order to improve immunotherapy treatments. https://icvi.org.uk/ however there are also lots of other good cancer charities in the UK and elsewhere, some of which also study immunotherapy.

Good question, the main myth is probably that the immune system of healthy people need to be boosted at all. The immune system is a tightly controlled system in which too much activation can be as bad as too little. Avoiding stress and unhealthy dietary choices and the regular intake of fruit and vegetables are likely more important to maintaining a healthy immune system.

Another myth is that supplementation will necessarily result in increased concentrations of a given vitamin or other compound. Our gut controls the amount of a substance that is absorbed from our diet, and our liver metabolises much of what is absorbed. It often isn't clear how best to increase the concentration of something (for example vitamin D) via supplementation. Some approaches involve daily vitamin D supplementation and other intermittent high dose vitamin D. Regardless of the approach, the range of serum vitamin D (the amount present in our blood) is very tightly controlled.

Studies have shown that exercise can have varied effects on markers of immune function (markers are used to infer how the immune or inflammatory system may function). Some studies suggest that regular light exercise may reduce inflammation whilst intense exercise may suppress immune function. Whether these observations have practical implications for peoples health isn't yet clear.

Immunotherapy is currently used to treated numerous different cancers. Immunotherapy typically depends upon cells called 'T-cells' which identify and kill tumour cells. Although Immunotherapy has been very successful for some patients with cancers such as Melanoma, Lung cancer or B-cell lymphoma it fails to work in many patients and is largely ineffective against some cancers. I'm interested in how to improve T-cell function, especially using safe, low cost interventions involving diet or the gut microbiome.

A healthy lifestyle, described in some of my other answers, is the best way to maintain a strong and balanced immune system in people who are otherwise not suffering from illness. The anti-inflammatory properties of phytochemicals present in fruit and vegetables, along with vitamin D supplementation may be helpful to manage inflammation and resolve immune responses, for example to acute respiratory infections, especially for people who are deficient in vitamin D. For people who are already ill with chronic diseases such as cancer it may not be possible to strengthen the immune system in this way, at least not without also using powerful immunotherapies prescribed by an Oncologist.

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For books on the immune system I would recommend 'Immune' by Philipp Dettmer. For a science book unrelated to immunology I wold recommend 'The Selfish gene' by Richard Dawkins.