Fruit · Kiwifruit

Kiwi: Nutrition Facts, Health Benefits, Skin & Side Effects

What a green or gold kiwi gives you, what human studies show for constipation, vitamin C, iron, blood pressure, energy and sleep, whether to eat the skin, and who should be careful.

By Dr. Josh Axe, DC, DNM, CNS·20-min read

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Evidence-based37 sources citedUpdated October 12, 2026

Published Oct 12, 2026Last updated Oct 12, 2026Editorial policyMedical review policyFact-checking policy

Green kiwi, the fuzzy-skinned variety used in the constipation trials.

The Dr. Axe Score™

7.0/10

Overall Dr. Axe Score · Kiwi

Kiwi's score reflects human trials of the whole fruit for several uses, led by constipation relief, and an exceptional amount of vitamin C for its calories.

Scientific Evidence

7.4/10

Human trials of the whole fruit for constipation, vitamin C, iron and blood pressure, and a national dietetic guideline for constipation.

Antioxidant & Anti-Inflammatory

6.6/10

Brings blood vitamin C to saturation; lowered oxidative damage to DNA in a human study of 24 adults.

Clinical Effectiveness

7.6/10

Two a day is an easy, guideline-backed habit for constipation, and it covers a full day's vitamin C.

Nutrient Density

6.2/10

71% of the daily value for vitamin C and 23% for vitamin K per green kiwi; modest amounts of most other nutrients.

Why this score?

Why Kiwi scores 7.0 / 10

Weighting: Evidence 30% · Antioxidant & Anti-Inflammatory 25% · Clinical Effectiveness 25% · Nutrient Density 20% (7.4×0.30 + 6.6×0.25 + 7.6×0.25 + 6.2×0.20 = 7.01, shown as 7.0).

A transparent, weighted index built for foods. See how it’s calculated →

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Kiwi at a glance

Kiwi is a small, sweet-tart fruit with green or gold flesh, and one green kiwi gives you 71% of a day's vitamin C in 42 calories.1 2 Two green kiwis a day is a guideline-backed food for constipation,3 and in human trials kiwi raised vitamin C4 and iron status,5 lowered blood pressure 6 and eased fatigue.7

Green or gold: gold has about twice the vitamin C; green has about twice the fiber and more vitamin K
Typical amount: two kiwis a day, the amount used in the constipation trials
Sleep: two kiwis an hour before bed is one of the food steps in my Deep Sleep Protocol 8
Skin: edible, with extra fiber; wash it well first
Main cautions: kiwi allergy, more likely if you're allergic to latex, and steady vitamin K intake on warfarin

Cut a kiwi in half and you'll find bright green or golden flesh around a ring of tiny black seeds, inside a thin skin you can eat. One green kiwi carries 64 milligrams of vitamin C, 71% of the daily value, in just 42 calories, and a gold kiwi carries about twice that.1 9 2

Kiwi also has human research behind it, done on the whole fruit. Two green kiwis a day eased constipation in a trial across three countries, and the British Dietetic Association now recommends kiwi in its national guideline for people with constipation.10 3 Other trials have tested kiwi for vitamin C status, iron, blood pressure, energy and sleep. In Italy, kiwi's vitamin C earned it the nickname frutto della salute, "the health fruit."11

What is kiwi fruit?

Quick answer

Kiwi, or kiwifruit, is the fruit of a woody vine in the Actinidia genus, with sweet-tart green or gold flesh, tiny edible black seeds and a thin skin.12 Green kiwi has a fuzzy brown skin, while gold kiwi's skin is smoother and its flesh is sweeter.12 1 9

Kiwi grew wild along China's Yangtze River valley before its seeds reached New Zealand in 1904. There the fruit was sold as the Chinese gooseberry until it was renamed for the country's national emblem, the kiwi bird, when exports took off around the 1960s.12 Today China, Italy, New Zealand, Chile and Greece grow 87% of the world's kiwis.12

There are more than 60 species. The fuzzy green kiwi, Actinidia deliciosa, is the most widely grown; gold and red-fleshed kiwis come from Actinidia chinensis; and the small, hairless kiwi berries come from Actinidia arguta.12

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Kiwi nutrition facts

Quick answer

One medium green kiwi (69 grams) has 42 calories, 10.1 grams of carbohydrate, 2.1 grams of fiber and 64 milligrams of vitamin C, 71% of the daily value, plus 23% of the daily value for vitamin K.1 2 A gold kiwi (81 grams) has 51 calories and 130 milligrams of vitamin C, 145% of the daily value.9

From USDA FoodData Central records for raw green kiwi (one 2-inch fruit) and raw gold kiwi (one fruit). % Daily Value uses FDA reference values.1 9 2

Nutrient	Green kiwi (69 g)	% DV	Gold kiwi (81 g)	% DV
Calories	42	n/a	51	n/a
Carbohydrate	10.1 g	4%	12.8 g	5%
Fiber	2.1 g	7%	1.1 g	4%
Total sugars	6.2 g	n/a	10.0 g	n/a
Protein	0.8 g	2%	0.8 g	2%
Vitamin C	64 mg	71%	130 mg	145%
Vitamin K	27.8 mcg	23%	4.9 mcg	4%
Copper	0.09 mg	10%	0.12 mg	14%
Vitamin E	1.0 mg	7%	1.1 mg	8%
Potassium	215 mg	5%	255 mg	5%
Folate	17 mcg DFE	4%	25 mcg DFE	6%
Lutein + zeaxanthin	84 mcg	n/a	19 mcg	n/a
Water	83.1%	n/a	82.4%	n/a

Vitamin C is kiwi's standout. One green kiwi covers most of a day's needs, and two cover all of it, with 128 milligrams.1 2 Because heat breaks down vitamin C, eating kiwi raw, the way most people do, avoids the losses cooked foods take.13 A green kiwi also brings a useful share of vitamin K and copper, and smaller amounts of vitamin E, potassium, folate and lutein.1

For a sweet fruit, kiwi is gentle on blood sugar. Green kiwi has tested 39.3 on the glycemic index and gold kiwi 48.5, both relatively low, and its 2.1 grams of fiber per green kiwi makes it an easy way to add fiber to your day.11 1

Green vs. gold kiwi: which is healthier?

Both are healthy, and each has its own strengths. Gold kiwi has about twice the vitamin C of green and tastes sweeter. Green kiwi has about twice the fiber and more than five times the vitamin K, and it scores lower on the glycemic index.1 9 11

Choose by what you're after. For constipation, choose green, the kiwi used in the constipation trials.10 14 15 For the most vitamin C per fruit, choose gold, the kiwi used in the vitamin C, iron and energy trials.4 5 7

Can you eat kiwi skin?

Quick answer

Yes. Kiwi skin is edible, and eating it adds fiber and the polyphenols concentrated in the peel.3 16 Green kiwi skin is fuzzy and gold kiwi skin is smoother; wash either one well before you eat it.

In a lab analysis of Actinidia chinensis, the species gold kiwi belongs to, peel extracts had more total phenolics than flesh extracts, 12.8 versus 9.5 milligrams per gram of dried fruit, measured as gallic acid equivalents.16 In a small study in Japan, healthy adults each ate a bread meal with gold kiwi flesh, with the flesh and its skin, and without kiwi, on separate days in random order. In the 12 whose results were analyzed, kiwi blunted the rise in blood sugar about as much with the skin as without it.17

For constipation, the trials used peeled kiwi, and the national dietetic guideline recommends peeled kiwi there. Its experts note that the skin adds fiber, which may help, though it could also add to side effects, something the trials didn't test.3 10 If peeled kiwi sits well with you, try a few slices with the skin on and see how your gut responds.

Kiwi is on my list of fruits to eat, and organic fresh or frozen fruit is best.18 If you eat the skin, choose organic kiwi when you can and rub it under running water with a clean cloth or vegetable brush to remove some of the fuzz. Thin rounds, skin on, are the easiest way to eat it whole.

What is kiwi good for?

Quick answer

Kiwi is best known for relieving constipation3 and raising vitamin C,4 and human trials also link it to better iron status,5 healthier blood pressure,6 more energy,7 longer sleep19 and less oxidative damage to DNA.20

Where the research stands

The kiwi research is on the whole fruit, green or gold, and it's strongest for constipation, where several trials, a review of 23 diet studies and a national dietetic guideline agree.10 21 3 The human studies on this page enrolled between 9 and 184 people, and most ran four to eight weeks. Much of the research was funded or supplied by the New Zealand kiwifruit growers' marketing company, while the national guideline and an independent review of diet studies for constipation point the same way.21 3

Kiwi benefits, graded by evidence strength (research on whole green or gold kiwi). Evidence labels are editorial judgments.
Benefit	Evidence	What was studied	What the research shows	Good to know
Constipation relief	Strong	2 green kiwis a day for 4 weeks	More than 1.5 extra complete bowel movements a week; fewer side effects than psyllium10 14	The trials used peeled kiwi
Vitamin C status	Strong	Half a gold kiwi to 2 a day	One a day reached healthy blood levels; two neared saturation4	Absorbed as fully as a tablet22
Iron status	Moderate	2 gold kiwis with an iron-fortified breakfast, 16 weeks	Stored iron rose more than with a banana5	Women with low iron stores
Blood pressure	Moderate	3 kiwis a day for 8 weeks	24-hour systolic pressure 3.6 points lower than with an apple a day6	Seen when pressure ran high, and in smokers
Energy and mood	Emerging	2 gold kiwis a day, 4 to 6 weeks	Less fatigue and better well-being at 2 weeks7 23	Strongest when vitamin C or mood started low
Protection from oxidative damage	Emerging	1 or 2 gold kiwis a day, 4 weeks each	Less oxidative damage to white blood cell DNA20	Healthy adults eating modest amounts of produce
Sleep	Emerging	2 kiwis an hour before bed	Total sleep rose from 361.8 to 416.6 minutes a night19	Adults with sleep problems, and elite athletes

How does kiwi work in your body?

Kiwi's best-studied effect, on constipation, runs through water. MRI scans show how it works. In a study of 14 healthy adults, each person ate two large kiwis twice a day for three days and, in a separate period, a calorie-matched drink, so each person tried both.24

1Fiber that holds water

A green kiwi carries 2.1 grams of fiber,1 and kiwi fiber has a high capacity to hold water.11

2More water in the small intestine

Over the scan day, the small intestine held more than twice as much water after kiwi as after a calorie-matched drink.24

3More volume in the colon

The same scans showed larger ascending colon and total colon volumes after the kiwi days.24

4Softer, more frequent stools

Stools came 1.46 times a day on kiwi versus 1.14 on the drink, and they were softer, scoring 4.1 versus 3.4 on the Bristol stool form scale.24

5Faster transit

In adults with IBS-C, two green kiwis a day for four weeks shortened the time it took food to move through the colon.15

Kiwi also carries actinidin, the most abundant protein in the fruit and an enzyme that breaks down other proteins, much like the protein-digesting digestive enzymes your own body makes. In lab models of digestion, kiwi extract helped break down proteins from milk, soy and meat.11 The same enzyme is kiwi's main allergen, which the side effects section covers.12

Kiwi benefits, ranked by evidence

Human research on whole kiwi supports six benefits, listed here in order of evidence strength: constipation relief, better vitamin C status, better iron status, healthier blood pressure, more energy and better mood, and protection from oxidative damage. Sleep has its own section after the rankings.

Constipation relief

Strong evidenceHuman studyRandomized trial of 184 adults · partly randomized trial of 79 · placebo-controlled study of 54 · review of 23 studies · national guideline

In a randomized trial across New Zealand, Italy and Japan, 184 adults, including 60 with functional constipation and 61 with irritable bowel syndrome with constipation (IBS-C), each ate two peeled green kiwis a day for four weeks and took psyllium, a fiber supplement matched for fiber, for another four weeks, so each person tried both. People knew which treatment they were on. Kiwi added 1.53 complete bowel movements a week without laxatives in functional constipation and 1.73 in IBS-C, clearing the trial's target of at least 1.5, while psyllium cleared it only in IBS-C. Across both constipation groups, kiwi's effect on that main measure was greater than psyllium's, though their week-by-week counts didn't differ, and kiwi did better than psyllium on straining, stool consistency and overall gut comfort.10

In a partly randomized U.S. trial of 79 adults with chronic constipation, two green kiwis a day, prunes and psyllium all increased complete bowel movements over four weeks; kiwi caused the fewest side effects, eased bloating and left the fewest people dissatisfied.14 In a Taiwanese study of 54 adults with IBS-C, the 41 who ate two green kiwis a day for four weeks had more bowel movements each week and faster colon transit by the end, while 13 took placebo capsules.15 A review of 23 diet studies found kiwi increased stool frequency by 0.36 bowel movements a week more than psyllium.21

On that evidence, the British Dietetic Association recommends two to three kiwis a day for at least four weeks for constipation, and it suggests kiwi over psyllium for people bothered by bloating, abdominal pain or gas. The same guideline found that kiwi supplements in capsules or sachets didn't change stool frequency or consistency, so eat the fruit itself.3 For more on gut-friendly eating with IBS, see the IBS diet, and for other gentle options, these natural constipation relief steps.

Study takeaway: two green kiwis a day for four weeks added more than 1.5 complete bowel movements a week in people with constipation.

Two green kiwis a day added more than 1.5 complete bowel movements a week

Source: Gearry et al. · Am J Gastroenterol, 2023 [10]

Better vitamin C status

Strong evidenceHuman studyStep-up dose study · 15 men · absorption studies of 9 and 36 men

The NIH lists kiwi among the good food sources of vitamin C, the nutrient your body uses to make collagen.13 In a New Zealand study with no comparison group, 15 young men with below-average vitamin C added gold kiwi in steps, half a kiwi a day, then one, then two, for several weeks at each step, and 11 of them finished every step. Their blood vitamin C rose from 38 µmol/L at the start to 50 on half a kiwi a day, 53 on one kiwi and 62 on two, and it fell back to 42 four weeks after they stopped. One kiwi a day lifted levels above 50 µmol/L, the level the researchers call healthy, and two a day moved them toward saturation, the point where extra vitamin C starts spilling into urine.4

When 9 men each took 200 milligrams of vitamin C once as gold kiwi and once as a chewable tablet, their blood levels matched, and a longer randomized study in 36 men found the same, so your body absorbs kiwi's vitamin C as completely as a tablet's.22 25 I've written that a whole orange or red pepper provides far more cellular benefit than an ascorbic-acid tablet, because nature packages vitamin C with everything your cells need to put it to work.26 A kiwi delivers its vitamin C with fiber, vitamin K, vitamin E and folate, which makes it a simple everyday pick among vitamin C foods. If you're worried you run low, these are the signs of vitamin C deficiency.

Study takeaway: one gold kiwi a day lifted blood vitamin C into the healthy range in young men who were running low.

Blood vitamin C climbed with each added gold kiwi a day

Source: Carr et al. · J Nutr Sci, 2012 [4]One kiwi a day lifted average levels above 50 µmol/L, the level the researchers call healthy; two a day moved them toward saturation.

Better iron status

Moderate evidenceHuman studyRandomized trial · 89 women · 16 weeks

Vitamin C helps your body absorb the iron in plant foods and fortified grains, and kiwi brings plenty of it to a meal.13 In a randomized trial in New Zealand, 89 women aged 18 to 44 with low iron stores ate an iron-fortified breakfast cereal with milk every day for 16 weeks, along with either two gold kiwis or one banana. Among the 69 women who finished, ferritin, the blood marker of stored iron, rose by a median of 10.0 µg/L in the kiwi group versus 1.0 in the banana group, and a second iron marker improved with kiwi as well.5 The cereal carried added iron, so the result shows what kiwi adds to an iron-rich meal. For more ways to build iron, see these iron-rich foods, and if you think you run low, a ferritin test can confirm iron deficiency.

Study takeaway: two gold kiwis with an iron-fortified breakfast raised stored iron in women with low iron stores.

I recommend cooking spinach and kale and then consuming them with a vitamin C-rich food like kiwi or strawberries or citrus fruits.Dr. Josh Axe, DC, DNM, CNSFrom 10 Signs You Have an Iron Deficiency (How to Boost Iron Naturally), The Dr. Josh Axe Show (2024), at 25:52

Healthier blood pressure

Moderate evidenceHuman studyRandomized trials · 118, 85 and 102 adults · 4 to 8 weeks

In a randomized trial in Norway, 118 adults with high-normal blood pressure or stage 1 high blood pressure ate either three kiwis a day or one apple a day for eight weeks. On 24-hour monitoring, systolic pressure ended 3.6 points lower and diastolic pressure 1.9 points lower in the kiwi group than in the apple group, though office readings and blood vessel function didn't differ.6 In 85 men with high cholesterol who didn't have high blood pressure, swapping two other fruit servings for two green kiwis a day for four weeks, in a study where each man tried both diets, didn't change blood pressure.27

In a randomized trial of 102 male smokers aged 44 to 74, systolic pressure fell 10 points and diastolic pressure 9 in the group eating three kiwis a day for eight weeks, a bigger drop than in a control group eating their usual diet, and platelet aggregation, a measure of how readily platelets clump together, fell 15%.28 Kiwi fits best as one part of an eating pattern built on whole foods, alongside other foods that lower blood pressure.

Study takeaway: three kiwis a day lowered 24-hour blood pressure more than an apple a day in adults whose pressure ran high.

More energy and better mood

Emerging evidenceHuman studyPlacebo-controlled trial · 167 young adults · randomized trials of 35 young men and 26 adults

In a placebo-controlled trial in New Zealand, 167 young adults with low vitamin C ate two gold kiwis a day, took a 250-milligram vitamin C tablet or took a placebo tablet for four weeks. Both the kiwi and the tablet brought blood vitamin C to saturation within two weeks. At two weeks, the kiwi group reported less fatigue, 3.8 points lower than placebo, and better well-being, 3.4 points higher, while the tablet group also reported better well-being, 2.8 points higher. By four weeks the differences from placebo were small enough that they could have been chance, though the kiwi group's well-being stayed higher through the two weeks after they stopped, and the researchers concluded that kiwi's other components may add to what its vitamin C does.7 23 It's a trial I point to when I explain why I favor vitamin C from whole foods.26

In a separate randomized trial, 35 young men with below-average vitamin C ate either half a gold kiwi or two gold kiwis a day for six weeks. Among the men whose mood was lowest at the start, two kiwis a day cut total mood disturbance by 38% and fatigue by 38% and raised vigor by 31%.29 In a 2025 trial in Australia, 26 adults with mild to moderate mood disturbance spent four weeks eating two gold kiwis a day and four weeks on their usual diet, in random order with a two-week break between, and people knew which period they were in; 23 finished. During the kiwi weeks, their total mood disturbance score fell 65%, from 27.6 to 9.6, and their well-being and vitality scores rose by week four, while none of these changed on their usual diet.30 For more food-first ways to lift your mood, see these mood-boosting foods.

Study takeaway: in young adults low in vitamin C, two gold kiwis a day eased fatigue and lifted well-being within two weeks.

Protection from oxidative damage

Emerging evidenceHuman studyHuman study · 24 adults · each tried both doses, 4 weeks each, in random order · no kiwi-free group

In Norway, 24 healthy adults who ate modest amounts of fruits and vegetables spent four weeks adding one gold kiwi a day and four weeks adding two, in random order with four kiwi-free weeks in between. Oxidative damage to the DNA in their white blood cells fell: one marker of it dropped 34% on one kiwi a day, and a second marker dropped on two a day. Their cells also held up better when exposed to a DNA-damaging chemical in the lab, while their triglycerides and platelet aggregation dropped. The study had no group that went without kiwi, and a marker of fat oxidation, malondialdehyde, didn't change.20 Alongside its vitamin C, a green kiwi gives you 1.0 milligram of vitamin E and 84 micrograms of lutein and zeaxanthin, both antioxidants.1

Study takeaway: one to two gold kiwis a day lowered oxidative damage to white blood cell DNA in healthy adults.

Does kiwi help you sleep?

Quick answer

Kiwi may help you sleep longer: in a four-week study of 24 adults with sleep problems, two green kiwis an hour before bed raised total sleep on a wrist monitor from 361.8 to 416.6 minutes a night, though the study had no comparison group.19 Two kiwis an hour before bed is one of the top 10 sleep foods in my Deep Sleep Protocol.8

The study was done in Taiwan, where the 24 adults who finished, 22 of them women, ate two green kiwis an hour before bed every night for four weeks. Besides sleeping nearly 55 minutes longer on the wrist monitor, they reported falling asleep faster in their sleep diaries, in 20.4 minutes instead of 34.3, and their sleep-quality scores improved by 42.4%. On the wrist monitor, time to fall asleep and time awake during the night also fell, though not by enough to rule out chance.19

Total sleep after four weeks of two kiwis an hour before bed

Source: Lin et al. · Asia Pac J Clin Nutr, 2011 [19]

Three more studies add to the picture. In 15 elite sailors and track athletes who ate two kiwis an hour before bed for four weeks, also without a comparison group, sleep in their diaries rose from 7.6 to 8.55 hours a night.31 In a trial of 74 students with insomnia, described in that athletes' study, the students ate 130 grams of kiwi or of pear an hour before bed for four weeks; sleep measured on a wrist monitor didn't differ between the groups, while the kiwi group rated their sleep quality and daytime functioning better.31 And when 24 young men each ate two fresh kiwis, dried kiwi powder or plain water with dinner on separate nights, both kiwi forms raised the next morning's urine level of a breakdown product of serotonin, and the dried powder improved morning alertness and vigor compared with water.32 The researchers suggested that changes in serotonin metabolism may be one way kiwi affects sleep.32

Ideally for dinner, you want to do high protein, high fiber and some healthy fats, and then you could also do a little bit of fruit, like tart cherries or kiwi. That's going to optimize your sleep.Dr. Josh Axe, DC, DNM, CNSFrom Why SLEEP is Medicine: My 4 Tips to Improve Energy, The Dr. Josh Axe Show (2026), at 41:37

Food is one part of a good night. My Deep Sleep Protocol pairs it with morning light, a cool, dark bedroom, and a verse or a short prayer as you lie down, such as this one:8 "I will both lay me down in peace, and sleep: for thou, LORD, only makest me dwell in safety" (Psalm 4:8, KJV). For more ways to rest well, see these natural sleep aids.

How many kiwis should you eat a day?

Quick answer

Two kiwis a day is a good everyday target and the amount used in most of the kiwi research. Two green kiwis a day for four weeks eased constipation, the national dietetic guideline recommends two to three a day for at least four weeks for constipation, and one gold kiwi a day lifted vitamin C into the healthy range.10 3 4

Timing depends on your goal. For sleep, eat your two kiwis about an hour before bed, as my Deep Sleep Protocol suggests; for constipation, the big trial didn't set a time of day, so eat them whenever suits you.8 10 The blood pressure trials used three a day.6 28

Rotate your fruit, too. On my show, I've said not to eat the same fruit every morning: have an apple one day, kiwi the next, then blueberries or mixed berries, because more plant variety tends to mean more diverse gut bacteria.33 If you're eating two kiwis a day for constipation, vary the other fruit you eat around them.

How to eat, buy and store kiwi

Halve it and scoop the flesh with a spoon for the simplest snack.

Slice it into goat's or sheep's milk yogurt or kefir just before you eat, since kiwi's enzyme can start breaking down milk proteins as it sits.11

Blend a strawberry kiwi smoothie with goat's milk yogurt for breakfast.

Top grilled wild salmon with a salsa of diced kiwi, red onion, cilantro and lime.

Serve kiwi with sautéed spinach or kale to pair its vitamin C with the iron in the greens.

Freeze thin slices for a cold, sweet treat after dinner.

Pick kiwis that give slightly when you press them gently. Firm kiwis ripen on the counter in a few days.

Store ripe kiwis in the refrigerator, and wash them just before eating if you plan to eat the skin.

Find it year-round. Kiwi grows in both hemispheres and stores well after harvest, so you can find it all year.11 In winter, I recommend focusing on seasonal fruits like oranges, grapefruit, lemons, tangerines and kiwi, some of the best winter fruits for eating seasonally.34

Not sure how kiwi fits your plan?

Ask Dr. Axe AI. Answers are grounded in this library, with sources shown.

Kiwi side effects and who should be careful

Quick answer

Kiwi is a safe everyday fruit for most people. The cautions are kiwi allergy, which is more likely if you're allergic to latex, birch pollen or certain other fruits, and keeping vitamin K intake steady if you take warfarin.12 35 36

Kiwi allergy and latex-fruit syndrome

Kiwi has become a major trigger of plant-food allergies, and kiwi allergy has been on the rise in recent years.12 Actinidin, the enzyme that makes up about half of kiwi's soluble protein, is its main allergen. Mild reactions are itching and tingling of the lips, mouth or tongue; severe ones include hives, swelling of the throat, vomiting, wheezing and a drop in blood pressure.12 People allergic to birch or grass pollen, latex, avocado, banana or hazelnut are more likely to react to kiwi, because their allergens resemble kiwi's.12

If you're allergic to latex, know that kiwi is one of the fruits most often behind latex-fruit syndrome, along with banana, avocado and papaya, and in the first study of the syndrome, 13 of 25 people with a latex allergy had it.35 Know the signs of a food allergy, and see the box below for what to do.

Does kiwi interact with medications?

The interaction to know is vitamin K. If you take warfarin, keep your vitamin K intake steady from week to week rather than avoiding vitamin K foods.36 A green kiwi has 27.8 micrograms of vitamin K and a gold kiwi 4.9, so eat about the same amount of kiwi each week, and tell the doctor who manages your warfarin before you make a big change.1 9

If you've been told to limit potassium, for example because of kidney disease, count the 215 milligrams in each green kiwi toward your daily limit.1

Who should be careful with kiwi:

If kiwi has given you an itchy or tingling mouth, hives or swelling, stop eating it and see an allergist
If eating anything leads to throat swelling, trouble breathing or dizziness, use your epinephrine if you carry it and call 911; it's an emergency

The bottom line

Is kiwi good for you?

Yes. A kiwi gives you most of a day's vitamin C in about 42 calories, along with fiber, vitamin K and vitamin E, and human trials have tested the whole fruit for several uses. Two green kiwis a day is a guideline-backed way to ease constipation, trials link kiwi to better vitamin C and iron status, healthier blood pressure and more energy, and two an hour before bed is one of the food steps in my Deep Sleep Protocol.3 8

Eat two a day, green for fiber or gold for extra vitamin C, skin and all if you like, and pair them with iron-rich meals. Skip kiwi if it makes your mouth itch or swell. It's a small, sweet habit that supports a body designed to heal.

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Kiwi: frequently asked questions

Is kiwi good for you?

Yes. One green kiwi gives you 71% of the daily value for vitamin C and 23% for vitamin K in 42 calories, and human trials link kiwi to easier bowel movements, better vitamin C and iron status, and healthier blood pressure.1 10 4 5 6

How many calories are in a kiwi?

About 42 calories in a medium green kiwi (69 grams) and 51 in a gold kiwi (81 grams), according to USDA FoodData Central.1 9

How much vitamin C is in a kiwi?

A medium green kiwi has 64 milligrams of vitamin C, 71% of the daily value, and a gold kiwi has 130 milligrams, 145% of the daily value.1 9 2

How many kiwis should you eat a day?

Two a day is a good target. Two green kiwis a day for four weeks eased constipation in trials, and two an hour before bed is the amount in my Deep Sleep Protocol; for vitamin C alone, one gold kiwi a day lifted blood levels into the healthy range.10 8 4

Can you eat kiwi skin?

Yes. The skin is edible and adds fiber, and in a lab analysis, kiwi peel had more polyphenols than the flesh. Wash it well first, and choose organic when you can.3 16

Is gold kiwi healthier than green?

Neither is healthier overall. Gold kiwi has about twice the vitamin C, while green kiwi has about twice the fiber, more vitamin K and a lower glycemic index, and green is the kiwi used in the constipation trials.1 9 11 10

Is kiwi high in sugar?

No. A green kiwi has 6.2 grams of natural sugar along with 2.1 grams of fiber, and it has tested 39.3 on the glycemic index, which is relatively low.1 11 As I've said on my show, sugar isn't the culprit; the problem is sugar without the fiber and nutrients of a whole food.37

Is kiwi good for constipation?

Yes. In a trial across three countries, two green kiwis a day for four weeks added more than 1.5 complete bowel movements a week in people with constipation, and the British Dietetic Association recommends two to three kiwis a day for at least four weeks.10 3

Does kiwi help you sleep?

It may. In a four-week study of 24 adults with sleep problems and no comparison group, two kiwis an hour before bed raised total sleep on a wrist monitor from about 6 hours to just under 7, and kiwi is one of the sleep foods in my Deep Sleep Protocol.19 8

Is kiwi good for women?

It can help women with low iron stores. In a 16-week randomized trial, among the 69 of 89 women with low iron stores who finished, two gold kiwis with an iron-fortified breakfast raised stored iron (ferritin) by a median of 10.0 µg/L, versus 1.0 with a banana.5

Is kiwi good for diabetics?

Kiwi can fit a blood-sugar-conscious diet. Green kiwi has tested 39.3 on the glycemic index and gold kiwi 48.5, and its low glycemic index has held up in people with type 2 diabetes as well as in healthy adults.11 In a small study of healthy adults who each tried every meal, swapping part of a bread meal's carbohydrate for gold kiwi lowered the peak blood sugar rise by 27.6%.17

Can you be allergic to kiwi?

Yes. Kiwi allergy can cause anything from an itchy mouth to anaphylaxis, and it's more likely if you're allergic to latex, birch pollen, avocado or banana.12 35

Why does kiwi make my mouth itch?

An itchy or tingling mouth after eating kiwi can be a mild allergic reaction to kiwi proteins, so stop eating it and see an allergist, especially if you also get swelling or hives.12

Does kiwi interact with blood thinners?

Yes, with warfarin: a green kiwi has 27.8 micrograms of vitamin K, so keep your kiwi intake steady from week to week rather than eating a lot one week and none the next.1 36

When is kiwi in season?

Kiwi is available year-round because it grows in both hemispheres and stores well after harvest, and it's one of the winter fruits I recommend.11 34

Freshness & update log

October 12, 2026 — Rewritten and re-sourced. Re-pulled the nutrition facts from USDA FoodData Central for green and gold kiwi, which corrects copper to 10% of the daily value per green kiwi; replaced the cancer, antimicrobial, eye-disease and collagen claims from lab studies with human research on constipation, vitamin C status, iron, blood pressure, energy and mood, oxidative damage and sleep; removed the comparison with oranges, the beta-blocker and pre-surgery advice and the question about dogs, none of which had a source; added gold kiwi, whether to eat the skin, how many kiwis to eat, kiwi allergy and latex-fruit syndrome, the warfarin note and the Dr. Axe Score.

References

Dr. Josh Axe, DC, DNM, CNS

Doctor of Natural Medicine · Founder, DrAxe.com

Dr. Axe is a certified doctor of natural medicine, clinical nutritionist, and multiple New York Times bestselling author. He has spent 20+ years in clinical practice helping people heal at the root cause and founded one of the most-visited natural-health platforms in the world.

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