Teaching pack: Diet, Exercise & Lifestyle

Obesity, alcohol and inactivity are established causes; diet quality, fibre and the gut microbiome shape immunotherapy response; structured exercise improved survival in a randomised colon cancer trial (CHALLENGE, 2025); fasting-mimicking and ketogenic diets, GLP-1 agonists, vitamin D and aspirin are under test. Cachexia and malnutrition during treatment are treatable and under-treated. The evidence ranges from strong to hype, and this front keeps the two apart.

• Alcohol reduction, pricing and cancer warning labels: Alcohol causes at least seven cancers and there is no safe threshold. Price, availability and cancer warning labels are the tools that work; most people still do not know alcohol causes cancer.
• Aspirin for cancer prevention and adjuvant therapy: Daily low-dose aspirin lowers bowel cancer risk in people with Lynch syndrome and appears to cut recurrence in bowel cancers with a particular mutation. In healthy older people it caused more harm than good.
• Bariatric surgery and cancer incidence: People with severe obesity who have weight-loss surgery develop about a third fewer cancers over the following decade, especially womb and other hormone-related cancers, than similar people who do not.
• Cachexia pharmacotherapy: GDF-15 blockade, anamorelin, olanzapine: Cachexia pharmacotherapy covers three drug approaches to cancer wasting: a new antibody that blocks the hormone suppressing appetite, an appetite hormone mimic approved only in Japan, and a very cheap old tablet. None is yet standard everywhere; all beat what came before.
• Cachexia-directed therapy (GDF-15 blockade): Treating the wasting that kills many cancer patients, by blocking the hormone that suppresses appetite.
• Chronotherapy: timing treatment to the body clock: Giving the same drug at a different time of day, because the body clock changes how much damage it does and how well the immune system responds.
• Coffee and tea intake: Coffee does not cause cancer and is probably protective against liver and womb cancer. Very hot drinks of any kind may raise oesophageal cancer risk.
• Dietary fibre and the gut microbiome for immunotherapy response: Patients who eat plenty of fibre and avoid probiotic pills seem to respond better to immunotherapy for melanoma, probably because fibre feeds the right gut bacteria. A proper trial is under way.
• Dietary supplements during cancer treatment: interactions and harms: Most people on cancer treatment take supplements, often without telling their team. Antioxidants, St John's wort, high-dose vitamins and some herbs can blunt chemotherapy or radiotherapy or interact with targeted drugs.
• Dietitian-led weight-loss programmes in HR-positive breast cancer: Being overweight after breast cancer is linked with more recurrence, so a 3,000-woman trial tested a two-year telephone weight-loss programme. Women lost weight, but the trial did not clearly show fewer recurrences.

• ALASCCA (phase 3, n=626): Time to recurrence at 3 years, group A (PIK3CA exon 9/20): 7.7% vs 14.1%, HR 0.49
• CHALLENGE (CCTG CO.21) (phase 3, n=889): Disease-free survival at 5 years: 80.3% vs 73.9%, HR 0.72
• ROMANA 1 and ROMANA 2 (phase 3, n=979): Change in lean body mass over 12 weeks (ROMANA 1): 0.99 kg vs -0.47 kg
• PREHAB: multimodal prehabilitation before colorectal cancer surgery (phase 3, n=251): Fewer severe complications and faster recovery with prehabilitation; surgery not delayed.
• Low-dose olanzapine for cancer anorexia (Tata Memorial) (phase 3, n=124): Weight gain greater than 5% at 12 weeks: 60% vs 9%
• Ponsegromab phase 2 in cancer cachexia (phase 2, n=187): Change in body weight at 12 weeks (placebo-adjusted): 2.81 kg vs 1.92 kg vs 1.22 kg vs 0 kg

1. What is exercise oncology and is there real evidence?
   Answer

   Structured exercise during and after treatment; the CHALLENGE trial (2025) randomised colon cancer survivors and showed improved disease-free and overall survival, the first level-1 evidence, plus less fatigue and neuropathy.

• WCRF Continuous Update Project: https://www.wcrf.org/research-policy/continuous-update-project/
• CHALLENGE trial (NEJM 2025): https://www.nejm.org/doi/full/10.1056/NEJMoa2502760