Serotonin, neuroendocrine tumours & your diet
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Should I avoid foods high in serotonin?
The only time you should avoid foods high in serotonin is before and during the 24-hour urine (pee) collection for the 5-HIAA test. Eating foods high in serotonin during this time may cause a false positive result.
Otherwise, it is not necessary to avoid foods high in serotonin if they do not trigger symptoms for you.
Serotonin in foods will not affect tumour growth.
Which foods are high in serotonin?
The following foods are high in serotonin and should be avoided if you are having the 24hour urine collection 5-HIAA test:
- Walnuts (black, English and butternuts)
- Cashew
- Coconut
- Banana
- Tomatoes
- Avocados
- Plums
- Grapefruit
- Cantaloupe
- Honeydew
- Olives
- Eggplant
- Pecans
- Plantains
- Pineapple
- Kiwi
- Dates
- Brazil nuts
- Almonds
- Shagbark
- Macadamia nuts
How long do I need to avoid these foods?
After the 24-hour urine collection, you can reintroduce the foods listed above into your diet.
Please contact your registered dietitian with any questions.
Adapted from: The Carcinoid Cancer Foundation (2008). Nutritional Concerns for the Carcinoid Patient: Developing Nutrition Guidelines for Persons with Carcinoid Disease.
