Orange — fruit card: vitamin C and some caution
Lankaran citrus fruits are the bright fruits of winter. The orange is a source of vitamin C, and its thick skin is peeled away. This card explains how to eat oranges during treatment and when to be careful.

01Short answer
02Simple explanation
Oranges: vitamin C.
Wash before peeling.
Acidity stings mouth sores.
Juice: pasteurised.
03Scientific explanation
Interactions: bitter (Seville) oranges contain furanocoumarins like grapefruit and can affect some medicines; ordinary sweet oranges carry little of this risk.
WHO: at least 400 g of fruit and vegetables a day is recommended; during treatment the amount may vary with appetite and your doctor’s advice.
FDA: wash produce under running water before cutting or peeling, because a knife can carry germs from the skin into the flesh.
04What happens in the body?
How to eat it
Wash, peel and divide into segments. Keeping the white pith adds fibre.

Juice
Sealed pasteurised juice; once opened, keep it in the fridge.

Washing and peeling
Wash your hands, rub the fruit under running water, dry it with a clean towel, then peel or cut it. Soap or bleach solutions are not needed.
Cut fruit
Keep cut fruit in the fridge and eat it within 1 day; do not leave it at room temperature for more than 2 hours.
05Fruit: four steps
Whole fruit, swap bruised, wash and peel, eat cut fruit soon.







06Key points at a glance
| Topic | In brief |
|---|---|
How to eat it | Wash, peel and divide into segments. Keeping the white pith adds fibre. |
Juice | Sealed pasteurised juice; once opened, keep it in the fridge. |
Washing and peeling | Wash your hands, rub the fruit under running water, dry it with a clean towel, then peel or cut it. Soap or bleach solutions are not needed. |
Cut fruit | Keep cut fruit in the fridge and eat it within 1 day; do not leave it at room temperature for more than 2 hours. |
07Key terms
- Folate
- A B vitamin needed for cell division.
- Furanocoumarins
- Compounds that affect how medicines are broken down.
- Neutropenia
- Low neutrophils, raising infection risk.
- Potassium
- A mineral for the heart and muscles.
- Fibre
- The part of plants that helps the gut work.
08Key points
- Oranges give vitamin C.
- Wash and peel.
- Care with mouth sores.
- Wash under running water.
- Eat cut fruit soon.
09Frequently asked questions
Do oranges interact with medicines?
Ordinary sweet oranges usually do not; bitter oranges and grapefruit do (see “Grapefruit — fruit card: the best-known food–drug interaction”).
Is fresh-squeezed juice allowed?
Squeezed at home from washed fruit and drunk at once, usually yes; during neutropenia ask your team.
Does this fruit treat leukemia?
No. It is a pleasant part of eating, not a treatment.
10Questions for your doctor
Take these questions to your appointment. The ones you save are collected on the “My questions” page and stay on this device only.
Do oranges interact with medicines?
Is fresh-squeezed juice allowed?
Does this fruit treat leukemia?
12Sources
- Leukemia & Lymphoma Society. Diet Guidelines for Immunosuppressed Patients
- U.S. FDA. Selecting and Serving Produce Safely
- NHS. 5 A Day: what counts?
- National Cancer Institute. Eating Hints: Before, During, and After Cancer Treatment
- USDA. FoodData Central
- Clinical Nutrition, 2021. ESPEN practical guideline: Clinical Nutrition in cancer
- National Cancer Institute (NCI). Constipation and Cancer Treatment
- World Health Organization (WHO). Drinking-water — fact sheet
- U.S. Food and Drug Administration (FDA). Grapefruit Juice and Some Drugs Don’t Mix
- National Center for Complementary and Integrative Health (NCCIH). Using Dietary Supplements Wisely
How to eat it
Juice
Washing and peeling
Cut fruit