Background: Methods: Results: Conclusions:

Introduction: Exercise is one of several factors known to lower the risk of developing cancer, as well as improve outcomes in patients already diagnosed. People who exercise after cancer have lower rates of cancer complications, treatment toxicities, relapse and improved survival. This review highlights the supportive data and biochemical processes, which explain these potential benefits. Sources of data: PubMed, Embase, Medline and Cochrane libraries were searched for papers which addressed the effects of exercise and physical activity on cancer for this review. The search terms used were physical activity, exercise and cancer up to February 2021. We also referred to the background research required for international exercise intervention study involving men with prostate cancer (INTERVAL-GAP4) and scrutinized references within the robust papers published on this subject to ensure we did not miss any clinically studies. One hundred and eighty eight papers were included. Areas of agreement: Exercise programmes mitigate many of the complications and risks associated with cancer, particularly thromboembolism, fatigue, weight gain, arthralgia, cognitive impairment and depression. Areas of controversy: Molecular and biomarker changes, resulting from exercise, suggest that exercise elicits beneficial changes in insulin-related pathways, down-regulates inflammation and serum oestrogen levels, and enhances oxidative, immune and cellular repair pathways. Nonetheless, the evidence remains preliminary. Growing points: The timing, intensity and challenges of prehabilitation, adjunct and rehabilitation exercise programmes are being increasingly understood but their implementation remains sporadic. Areas for developing research: More robust clinical trial data are needed to substantiate a causal effect of exercise on overall and cancer-specific survival. These studies are ongoing. Research evaluating the most cost-efficient ways of incorporating prehabilitation, adjunct and rehabilitation programmes into routine practice would be helpful to funding bodies and health care strategists.

Gut microflora dysbiosis affects the majority of individuals after COVID-19, contributing to both gastro-intestinal (GI) and non-GI symptoms. Natural phytochemicals have reported anti-viral properties and favourable effects on inflammatory and oxidative pathways, both important for tissue damage post-viral pneumonia. This study involved 147 participants with symptomatic COVID-19, randomised to receive a placebo (P) or a phytochemical-rich concentrated food capsule (PC) in addition to a pre/probiotic lactobacillus capsule. Participants taking the PC had an almost two-fold reduction in mean fatigue scores compared to P [p = 0.02], a three-fold reduction in cough score and more than a double improvement in overall well-being scores [p = 0.02]. Two (1.5%) participants reported mild, increased bloating which they felt was attributable to the capsules, although GI symptoms improved in 25 of 31 participants (82%) who reported them at baseline. Sedentary, older, previously hospitalised men with GI symptoms had a statistically significantly improvement among those given the probiotic. Although some participants with early disease would have improved spontaneously, such a rapid improvement observed in the majority of participants, who had been suffering for an average of 108 days, was clinically relevant and welcomed, especially among those more likely to have pre-existing gut dysbiosis. We are now evaluating whether this blend could also enhance antibody titres post-COVID-19 vaccination.

Tea contains polyphenols such as flavonoids, anthocyanidins, flavanols and phenolic acids which in laboratory studies have reported to promote antioxidant enzyme formation, reduces excess inflammation, slow cancer cell proliferation and promote apoptosis. Evidence from epidemiological studies on the effect of tea consumption on prostate cancer (CaP) incidence has been conflicting. We analysed data from 25 097 men within the intervention arm of the 155 000 participant Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. Histologically confirmed cases of prostate cancer were reported in 3088 men (12·3 %) during the median 11·5 year follow-up. Tea consumption was assessed with a FFQ. Baseline characteristics were compared between groups using χ² and Kruskal–Wallis tests. Cox regression models were used to assess associations between tea intake and CaP incidence. There was no statistical difference between the risk of CaP between men who never drank tea to those who drank tea at any quantity. Amongst tea drinkers, those in the highest third of consumption group had a small but significantly lower risk compared with those in the lowest third (11·2 % v. 13·2 % hazard ratio 1·16; (95 % CI 1·05, 1·29), P = 0·004). This pattern persisted with adjustments for demographics and lifestyle. In conclusion, among tea drinkers, there was a small positive association between drinking tea and a reduced risk of prostate cancer. It does not support starting to drink tea, if men previously did not, to reduce the risk. Further research is needed to establish whether tea is justified for future prospective nutritional intervention studies investigating CaP prevention.

Men on active surveillance (AS), with prostate cancer, are very interested in dietary strategies that could improve their symptoms and help prevent progression of their disease. In this real-world trial involving 208 men, intake of phytochemical-rich food capsules helped slow prostate-specific antigen (PSA) progression significantly, and improved urinary symptoms and erectile function. What was novel about this study was that men randomised to take an additional blend of five Lactobacillus probiotics had a further three-fold slowing of PSA progression as well as reduction of inflammation. Currently, nearly 50% of men opt out of AS within 5 yr. If confirmed with further follow-up, these dietary interventions, alongside other lifestyle manoeuvres, could reassure men to remain on AS, and hence avoid the risks of radiotherapy, hormones, or surgery.