Staying hydrated during treatment
Drinking enough fluids is important during cancer treatment, especially if you have increased fluid losses from vomiting or diarrhoea. Not drinking enough can lead to dehydration. Dehydration occurs when the body doesn’t have enough water to carry out normal functions. Signs of dehydration can include less frequent urination or very dark urine, headaches, dizziness, dry mouth and low blood pressure 1,2.
Tips to Stay Hydrated
- Aim for 8–10 glasses (about 1.8–2.3 litres) of fluids each day. This amount can vary depending on your height, weight and how much fluid you need to replace losses 1,3.
- Measure how much your drinking glasses hold so you can track your intake. Many tall glasses hold more than one cup 1.
- Keep a water bottle or beverages nearby at all times 1.
- Set reminders around the house to drink regularly 1.
- Make a simple chart with boxes and tick off a box for each cup of fluid you drink 1.
- Thirst isn’t always a good indicator of dehydration, so drink based on your daily goal rather than waiting until you feel thirsty 2.
- If you can’t drink large amounts at once, take small sips throughout the day 1.
- Include foods with high fluid content such as ice blocks, jelly, Italian ice, soups, smoothies and watermelon 1,3.
- Avoid alcoholic drinks and limit caffeinated beverages, as they can increase fluid loss 1,3.
- Other beverage ideas include sparkling water, juices, sports drinks, broth, flavoured waters and oral nutrition supplements 1,3.
References:
1. Cancer Council NSW. Hydration during cancer treatment [Internet]. Sydney: Cancer Council NSW; 2025 [cited 2025 Nov 18]. Available from: https://www.cancercouncil.com.au/cancer-information/living-well/nutrition-and-cancer/treatment-side-effects-and-nutrition/hydration/
2. eviQ. Dehydration and fluid intake during cancer treatment – Information for patients [Internet]. Sydney: Cancer Institute NSW; 2023 [cited 2025 Nov 18]. Available from: https://www.eviq.org.au/patients-and-carers/side-effects/dehydration
3. Queensland Health. Nutrition tips for staying hydrated [Internet]. Brisbane: Queensland Health; 2018 [cited 2025 Nov 18]. Available from: https://www.health.qld.gov.au/__data/assets/pdf_file/0026/154394/oncol_hydration.pdf
Know more about the subject
Safe food handling with a weakened immune system
Common Questions About Hair Loss During Cancer Treatment
Hair loss is often associated with cancer treatment, but not everyone will experience it.
What Everyday Changes Are Necessary During Cancer Treatment?
Cancer treatment can bring changes to your daily life, but with a few simple adjustments, you can continue many of your usual activities and maintain a good quality of life.
How to Prepare for Cancer Treatment Sessions
A few simple tips to eat well, stay comfortable, and manage your daily routine while undergoing cancer treatment.
Vitamins and Minerals That Play a Major Role in the Battle Against Cancer
Ask your doctor or nutritionist about the need of taking vitamin and mineral supplements. Food supplements should not be used as a substitute for a varied diet.
