Kiwi holds nearly twice the vitamin C of an orange. But recent research has focused elsewhere.
In randomised trials on chronic constipation, two kiwifruit a day matched or beat prunes and psyllium for improving bowel movements, with less abdominal discomfort. The explanation is its unusual fibre structure, which holds on to water.
Key benefits
It improves bowel frequency and comfort
Several randomised trials in chronic constipation found two a day increased weekly bowel movements and reduced bloating. Unlike stimulant laxatives, it is not habit-forming.
Exceptionally dense in vitamin C
93 mg per 100 g, roughly twice an orange. Gold kiwi is higher still. One fruit comfortably exceeds the daily requirement.
Actinidin aids protein digestion
Kiwi's protease actinidin speeds the breakdown of meat and dairy proteins in the stomach. Using kiwi to tenderise meat works on the same principle.
It appears in sleep quality research
A small trial found better sleep duration and efficiency after four weeks of eating two kiwifruit an hour before bed. The sample was small, so treat it as preliminary.
How to eat it well
- The skin is edible and substantially increases the fibre. Scrub it, or choose gold kiwi if the fuzz bothers you.
- Do not let it sit in dairy. Actinidin breaks down milk protein and turns it bitter. Add it to yoghurt right before eating.
- To ripen a hard one, put it in a paper bag with an apple.
- Do not marinate meat longer than 30 minutes or the texture collapses.
- For constipation, follow the studied protocol: two a day, consistently.
What to watch out for
- With latex, avocado or banana allergy, cross-reaction is possible. Kiwi is among the more common food allergens in children.
- It contains oxalate, so avoid large amounts with a history of calcium oxalate stones.
- Actinidin can make the tongue tingle or sting. Cooking removes this.
- On warfarin, keep vitamin K intake steady.
Nutrition
Approximate values per 100 g edible portion.
- Calories
- 61 kcal
- Carbohydrates
- 14.7 g
- Fiber
- 3.0 g
- Sugars
- 9.0 g
- Protein
- 1.1 g
- Vitamin C
- 93 mg
- Vitamin K
- 40 µg
- Potassium
- 312 mg
Key nutrients
- Vitamin C
- Vitamin K
- Fiber
- Potassium
- Folate