Managing Weight Gain During and After Cancer Treatment
Being diagnosed with cancer and going through treatment can affect your body in many ways. Some people lose weight, while others gain weight. Weight changes are common and often linked to treatment, side effects, lifestyle changes, or the type of cancer.
Even if you are gaining weight during treatment, there are steps we can explore to help manage weight changes and feel confident about your food choices.
Why Weight Gain Happens
1. Treatment-related changes
- Hormone therapy most frequently used for breast, prostate, ovarian cancers can lower hormone levels which can lead to weight gain
- Corticosteroids can: Increase appetite, cause fluid retention (also known as edema symptoms include swelling in hands, feet, face), change body shape (changes include developing a puffy face, rounded back of neck, larger abdomen)
- Chemotherapy can slow metabolism, cause fluid retention, or trigger menopause which can affect weight.
2. Eating changes
- Nausea, anxiety, or depression → cravings for carbs or sweets
- Eating more to cope → may cause weight gain
3. Activity changes
- Fatigue → less physical activity → fewer calories burned
4. Cancer-related fluid buildup
- Some cancers (ovarian, colorectal) may cause fluid in legs or abdomen → edema or ascites
Signs of Fluid Retention
- Skin feels tight or stiff
- Rings, bracelets, shoes feel tighter
- Indentations remain after pressing skin
- Swelling in hands, feet, or legs
Tip — Contact your healthcare team if fluid retention appears suddenly.
Tips to Manage Weight
1. Focus on your meals
- Follow Canada’s Food Guide: ½ plate fruits & vegetables, ¼ plate protein foods, ¼ plate whole grains
- Choose fibre- and protein-rich foods → helps you feel full
- Drink water as your main beverage
2. Eat mindfully
- Enjoy meals with family or friends
- Put away TV, phones, and electronics while eating
- Eat when hungry, stop when full
3. Move your body
- Physical activity helps manage weight, mood, and fatigue
- Check with your healthcare team before starting exercise
4. Track your progress
- Keep a food diary or note activity
- Focus on small, realistic changes
Tips to Manage Fluid Retention
- Limit salty foods → salt makes your body hold water
- Avoid standing long periods → raise feet when resting
- Don’t cross legs while sitting
- Avoid tight clothing or jewelry
- Your healthcare team may suggest medications (diuretics) if needed
When to Seek Support
Dietitian:
- Helps understand why weight is changing
- Guides healthy food choices
- Supports realistic weight goals
Healthcare team:
- Checks for underlying causes
- Advises safe exercise and medications
Remember
Weight gain during cancer treatment is common and often temporary. You have some control, but perfection isn’t expected. Being patient and seeking support is the best way to protect your health and well-being.
Connect with your dietitian if you have questions or need guidance. You don’t have to navigate these changes alone.