Action / Info
💧 Staying properly hydrated
How much and how to hydrate correctly during cancer treatment.
How much fluid do you need?
ESPEN recommends an intake of 30–40 ml of fluid per kilogram of body weight per day — for a person weighing 70 kg, that means roughly 2.1–2.8 liters. Water is the main source, but stewed-fruit drinks, herbal tea, soups and drinkable yogurt also count. If you have frequent vomiting or diarrhoea, your needs may be higher — discuss this with your medical team.
Signs of dehydration to watch for
Dark-colored urine (darker than pale yellow) is the simplest indicator. Other signs include a dry mouth, dizziness when standing up, increased fatigue and passing less urine. On chemotherapy days or after radiotherapy, actively monitoring your hydration is essential.
Practical tips for staying hydrated
If you do not like plain water, add a few mint leaves, slices of cucumber or a drop of lemon. Ginger or chamomile tea can settle the stomach and helps with hydration. Avoid too much caffeine — coffee and black tea have a mild diuretic effect. Alcohol is not advised during most cancer treatments.
Key points
What to remember from this article
- ✓30–40 ml per kg of body weight per day is the basic requirement
- ✓Pale yellow urine indicates good hydration
- ✓Vomiting and diarrhoea increase fluid needs
- ✓Soups, stewed-fruit drinks and herbal teas contribute to hydration
Related practical guides
Concrete tips for similar situations
Medical note
The information in this article is for guidance only and is based on international guidelines (ESPEN, Canadian Cancer Society, Memorial Sloan Kettering). It does not replace individualized medical advice. Discuss any nutrition decision with your medical team or an oncology nutritionist.
Sources
- ESPEN Guidelines on Nutrition in Cancer Patients, 2021
- Canadian Cancer Society – Drinking enough fluids
- Memorial Sloan Kettering Cancer Center – Hydration during chemotherapy