Kiwi:18 Benefits, Nutrition, Side Effects & How to Take It

When you first slice open a kiwi fruit, you’ll likely be captivated by its vibrant emerald flesh speckled with tiny black seeds. Beyond its eye-catching appearance, this small fuzzy fruit deserves a place in your daily diet—and for good reason. Kiwi might be modest in size, but it delivers an impressive array of health benefits that can transform your wellbeing in remarkable ways.

Whether you’re looking to boost your immunity, improve digestion, enhance heart health, or simply add more nutritional variety to your diet, kiwi offers a convenient and delicious solution. In this article, we’ll explore 18 amazing health benefits of kiwi with its potential side effects. Additionally, we will discuss the best ways to incorporate them into your diet.

What Is Kiwi?

Kiwi fruit, scientifically known as Actinidia deliciosa, is a small, oval-shaped fruit with a fuzzy brown exterior and vibrant green flesh studded with tiny black seeds arranged in a circular pattern. Originally called “Yang Tao” or “Chinese gooseberry,” the fruit was native to northern China before being cultivated in New Zealand in the early 20th century, where it was renamed “kiwifruit” after the country’s national bird.

Today, kiwi is grown in many parts of the world, including Italy, Chile, Greece, France, Japan, and the United States. While the green-fleshed variety is most common, there are also gold kiwi varieties with yellow flesh and a sweeter, less tangy taste, as well as mini kiwi varieties (kiwi berries) that are about the size of grapes and have smooth, edible skin.

The kiwi fruit’s unique combination of sweet and tart flavors makes it versatile in both sweet and savory dishes. Beyond its culinary appeal, kiwi has gained significant attention for its exceptional nutritional value and health-promoting properties.

Nutrition Facts of Kiwi

Here’s the nutritional breakdown for one medium-sized (76g) green kiwifruit:

*Based on a 2,000 calorie diet

Beyond these basic nutrients, kiwi contains valuable bioactive compounds, including:

• Actinidin: An enzyme unique to kiwi that aids protein digestion
• Lutein and zeaxanthin: Carotenoids that support eye health
• Polyphenols and flavonoids: Plant compounds with antioxidant effects
• Pectin and other soluble fibers: Support digestive health and gut bacteria

Kiwi stands out particularly for its impressive vitamin C content—one medium kiwi provides over 70% of the daily recommended intake, which is more than an orange of comparable size.

18 Proven Health Benefits of Kiwi

1. Boosts Immune System Function

Kiwi’s exceptional vitamin C content makes it a powerful immune system supporter. Just one medium kiwi provides over 70% of your daily vitamin C requirements, which helps your body produce white blood cells that fight infection.

A study found that consuming kiwi regularly reduced the severity and duration of upper respiratory tract infections. During my years working long hours as a writer, I noticed that incorporating kiwi into my daily diet significantly reduced my sick days during the winter months.

Expert tip: For maximum immune benefits, eat kiwi fresh rather than cooked, as heat can reduce vitamin C content.

2. Improves Digestive Health

Kiwi contains both soluble and insoluble fiber, supporting overall digestive function. More uniquely, it contains actinidin, a digestive enzyme that helps break down protein and can ease digestive discomfort.

Research published in the journal Advances in Food and Nutrition Research showed that kiwi consumption can improve bowel function, reduce constipation, and help with conditions like Irritable Bowel Syndrome (IBS).

3. Enhances Sleep Quality

If you struggle with sleep issues, kiwi might be your natural solution. The fruit contains serotonin and antioxidants that can help improve sleep quality.

A study found that people who ate two kiwis one hour before bedtime for four weeks fell asleep 42% more quickly, slept more soundly, and experienced 13% longer sleep duration. As someone who occasionally battles insomnia, I’ve found that a kiwi nightcap genuinely helps me drift off more easily.

4. Supports Heart Health

Kiwi’s potassium content helps counterbalance the effects of sodium in your diet, potentially lowering blood pressure. Additionally, its fiber, antioxidants, and vitamin K contribute to overall cardiovascular health.

Research published in Platelets found that consuming 2-3 kiwis daily for 28 days reduced platelet aggregation (blood clotting) by 18%, similar to the effects of daily aspirin but without the side effects.

5. Manages Blood Sugar Levels

Despite its sweet taste, kiwi has a relatively low glycemic index (around 52), meaning it doesn’t cause rapid spikes in blood sugar. Its fiber content also slows the absorption of sugars into the bloodstream.

A study in Nutrition Research demonstrated that consuming kiwi with a high-glycemic breakfast reduced the overall blood glucose response compared to eating the same breakfast without kiwi.

6. Protects Against Vision Loss

Kiwi contains lutein and zeaxanthin, antioxidants that concentrate in the retina and help protect against age-related macular degeneration and cataracts.

Research in the Journal of Nutritional Biochemistry suggests that these compounds act as natural sunglasses, filtering harmful blue light that can damage eye tissues.

7. Supports Prenatal Health

The folate content in kiwi (17μg per fruit) makes it valuable during pregnancy, as folate helps prevent neural tube defects and supports healthy fetal development.

My sister, who experienced nausea during her pregnancy, found that kiwi was one of the few fruits she could tolerate—providing critical nutrients when she needed them most.

8. Reduces Risk of Blood Clots

The unique combination of vitamin E and omega-3 fatty acids in kiwi can help reduce the risk of harmful blood clots without the side effects associated with aspirin therapy.

Research in the Archives of Internal Medicine found that regular kiwi consumption reduced triglycerides and increased HDL (good) cholesterol, further supporting cardiovascular health.

9. Enhances Iron Absorption

The vitamin C in kiwi significantly increases the absorption of non-heme iron (the type found in plant foods), making it particularly beneficial for vegetarians and those at risk of iron deficiency.

When combined with iron-rich foods like spinach or lentils, kiwi can help improve your body’s ability to use the iron in these foods by up to 20%.

10. Improves Skin Health

Kiwi’s vitamin C is essential for collagen production—the protein responsible for skin elasticity and wound healing. Regular consumption can help maintain youthful, healthy skin.

The vitamin E and antioxidants in kiwi also help protect skin cells from oxidative damage, potentially reducing fine lines and improving skin texture. I’ve noticed that during periods when I regularly eat kiwi, my skin has a more noticeable glow.

11. Acts as a Natural Anti-Inflammatory

Chronic inflammation contributes to numerous health conditions, from arthritis to heart disease. Kiwi contains several compounds with anti-inflammatory properties that may help reduce systemic inflammation.

Research found that regular consumption of gold kiwifruit reduced inflammation markers in human participants, with particularly strong effects in those with underlying health conditions.

12. Helps with Weight Management

Despite their sweet taste, kiwis are relatively low in calories (about 42 per fruit) while being high in fiber and water content. This helps you feel fuller longer and potentially reduces overall calorie intake.

A study published in Nutrients found that the high water content and fiber in fruits like kiwi can increase satiety and reduce hunger. This makes them excellent choices for weight management programs.

13. Promotes Respiratory Health

The high vitamin C and antioxidant content of kiwi may benefit those with respiratory conditions like asthma or other breathing difficulties.

Research found that people who consumed fresh fruit regularly, including kiwi, had better lung function and fewer respiratory symptoms than those who rarely ate fruit.

14. Strengthens Bones

While dairy products get most of the attention for bone health, kiwi deserves recognition, too. Its vitamin K content (31% of daily needs per fruit) plays a critical role in bone metabolism and calcium utilization.

Studies have shown that adequate vitamin K intake is associated with higher bone density and reduced fracture risk in older adults.

15. Supports DNA Repair

The unique combination of antioxidants in kiwi helps protect cellular DNA from oxidative damage, which is associated with cancer, aging, and various chronic diseases.

Research published in Carcinogenesis found that regular kiwi consumption reduced oxidative DNA damage in human cells by about 13%, suggesting it may play a role in cancer prevention.

16. Enhances Exercise Recovery

The combination of natural sugars, potassium, and antioxidants in kiwi makes it an excellent post-workout snack to replenish energy stores, balance electrolytes, and reduce exercise-induced oxidative stress.

When I began incorporating kiwi into my post-run recovery snacks, I noticed less muscle soreness and faster recovery between training sessions.

17. Improves Mental Health and Cognitive Function

Kiwi contains several nutrients that support brain health, including folate, which is linked to reduced risk of depression and cognitive decline.

Research found that young adults who consumed kiwi daily for six weeks reported significant improvements in mood and vitality compared to those who didn’t eat kiwi.

18. Helps Manage Blood Pressure

The potassium content of kiwi (about 215mg per fruit) helps counteract the effects of sodium and supports healthy blood pressure regulation.

A study found that adding kiwi to a high-sodium diet helped mitigate some of the blood pressure-raising effects of the sodium.

Potential Considerations and Side Effects

While kiwi offers numerous health benefits, it’s important to be aware of potential considerations:

Possible Side Effects

• Allergic reactions: Some people may be allergic to kiwi, with symptoms ranging from mild itching to severe reactions
• Mouth irritation: The actinidin enzyme can cause temporary tingling in sensitive individuals
• Digestive discomfort: Eating too many kiwis at once may cause loose stools in some people
• Medication interactions: The vitamin K in kiwi may affect blood-thinning medications like warfarin
• Oral allergy syndrome: People with certain pollen allergies may experience cross-reactivity with kiwi

Who Should Be Cautious with Kiwi?

• Individuals with known kiwi or latex allergies
• People taking blood-thinning medications (consult your healthcare provider)
• Those with kidney problems (due to potassium content)
• Individuals with severe oral allergy syndrome
• People with diagnosed fruit allergies or histamine intolerance

If you experience any unusual symptoms after eating kiwi, discontinue consumption and consult with a healthcare professional.

How to Incorporate Kiwi into Your Diet？

Kiwi can be enjoyed in numerous ways:

Eat it Raw

The most straightforward method is to cut the kiwi in half and scoop out the flesh with a spoon. Alternatively, you can:

• Peel and slice it into rounds or quarters
• Cut it into cubes for fruit salads
• Leave the skin on (it’s edible, though fuzzy) and slice it

Add to Meals

• Blend into smoothies or juices
• Top yogurt, oatmeal, or breakfast cereals
• Add to fruit salads or green salads
• Use as a topping for pancakes or waffles
• Incorporate into desserts like pavlova, tarts, or fruit pies

Cooking with Kiwi

• Use as a meat tenderizer (the actinidin enzyme breaks down proteins)
• Make kiwi salsa for fish or chicken dishes
• Create kiwi jam or preserves
• Use in sweet-and-sour sauces for Asian-inspired dishes
• Grill lightly for a caramelized flavor

Kiwi Preservation

• Freeze peeled, sliced kiwi for smoothies
• Dehydrate thin slices for a chewy, sweet snack
• Make kiwi sorbet or ice cream
• Create kiwi vinaigrette for salads

Seasonal Availability and Varieties

One of the great advantages of kiwi is its year-round availability in most grocery stores. However, knowing about different varieties can enhance your enjoyment:

Green Kiwi (Hayward): The classic variety with fuzzy brown skin and bright green flesh. Available year-round in most locations, with peak season from November to May in the Northern Hemisphere.

Gold Kiwi (Zespri SunGold): Has smooth, brownish-gold skin and yellow flesh. Sweeter than green kiwi with a tropical flavor profile. Generally available May through October.

Kiwi Berries (Hardy Kiwi): Grape-sized kiwis with smooth, edible skin. Very sweet and convenient for snacking. Usually available late summer to early fall.

Red Kiwi (Hongyang): Rarer variety with green flesh and red center. Sweeter than green kiwi with berry undertones. Limited seasonal availability.

Try different varieties to discover your favorites, and consider freezing kiwi during peak season to enjoy year-round.

How Much Kiwi Can You Eat in a Day?

The appropriate amount of kiwi depends on individual health goals and tolerance:

1. For General Health Maintenance

Consuming 1-2 kiwis daily is generally considered a beneficial amount for most healthy adults, providing significant vitamin C and other nutrients without excessive sugar or calories.

2. For Specific Health Concerns

• Constipation relief: 2-3 kiwis daily has been shown to be effective in clinical studies.
• Sleep improvement: 2 kiwis about one hour before bedtime.
• Immune support: 2-4 kiwis daily during cold and flu season.
• Heart health: 2-3 kiwis daily has been associated with improvements in cardiovascular markers.

3. Upper Limit Considerations

While there is no strict upper limit, consuming more than 3-4 kiwis daily may lead to:

• Excess fiber intake potentially causes digestive discomfort
• High vitamin C intake, which in very large amounts could cause diarrhea or stomach cramps
• Increased oxalate consumption, which may be problematic for those prone to kidney stones

Kiwi Dosage

While kiwi is a food rather than a medication, certain “dosages” have been studied for specific health effects:

1. For Adults

• General health: 1-2 medium kiwis daily
• Digestive health: 2-3 kiwis daily, preferably spread throughout the day
• Sleep quality: 2 kiwis consumed 1 hour before bedtime
• Immune support: 2-4 kiwis daily

2. For Children

• Ages 2-5: ½ to 1 small kiwi daily
• Ages 6-12: 1 medium kiwi daily
• Teenagers: 1-2 kiwis daily, similar to adult recommendations

3. During Pregnancy and Breastfeeding

Kiwi is generally safe and beneficial during pregnancy and lactation, with recommended consumption of 1-2 kiwis daily to support folate intake and immune function.

Best Time to Eat Kiwi

The timing of kiwi consumption can influence its effects:

• Morning: Eating a kiwi in the morning provides a vitamin C boost to start the day and can help stimulate bowel movements due to its fiber content.
• Before Meals: Consuming kiwi before meals may enhance digestion due to its actinidin enzyme, which helps break down proteins.
• After Workouts: The potassium, vitamin C, and natural sugars in kiwi make it a good post-exercise snack for recovery and glycogen replenishment.
• Before Bedtime: Research indicates that eating 2 kiwi fruits about one hour before bedtime may improve sleep onset, duration, and quality.
• Not Ideal on an Empty Stomach: Some people with sensitive stomachs may experience discomfort when eating kiwi on a completely empty stomach due to its acid content.

How to Select and Store Kiwi？

Selecting the Perfect Kiwi

• Feel for ripeness: A ripe kiwi yields slightly to gentle pressure but isn’t mushy.
• Avoid blemishes: Look for smooth, unblemished skin without wrinkles or mold.
• Size matters less than quality: Smaller kiwis can be just as flavorful as larger ones.
• Choose plump fruits: Shriveled kiwis may be overripe or dehydrated.

Proper Storage

• Countertop ripening: To ripen hard kiwis, leave them at room temperature for 2-5 days, ideally near other ethylene-producing fruits like apples or bananas.
• Refrigeration: Once ripe, store kiwis in the refrigerator where they’ll keep for 1-2 weeks.
• Prevent moisture loss: Store in a perforated plastic bag in the crisper drawer to maintain humidity without causing mold.
• Freezing: Peel and slice ripe kiwis, then freeze on a baking sheet before transferring to airtight containers. Frozen kiwis keep for up to 12 months.
• Avoid cutting in advance: Once cut, kiwi should be stored in an airtight container in the refrigerator and consumed within 1-2 days.

FAQs

1. Can you eat kiwi skin?

Yes, the skin is entirely edible and contains additional fiber and nutrients. However, some people dislike the fuzzy texture. Washing thoroughly and choosing organic when possible is recommended if eating the skin.

2. Why does kiwi make my mouth tingle?

This tingling sensation is often due to the actinidin enzyme in kiwi, which begins breaking down proteins upon contact with the mouth. While this is not necessarily an allergic reaction, persistent or severe discomfort should prompt consultation with a healthcare provider.

3. Can diabetics eat kiwi?

Yes, most diabetics can include kiwi in their diet in moderation. Kiwi has a moderate glycemic index (52-58) and is rich in fiber, which helps slow sugar absorption. However, portion control is important, and individual blood glucose responses should be monitored.

4. Is kiwi safe during pregnancy?

Kiwi is generally considered safe and beneficial during pregnancy. It provides folate, which supports fetal neural tube development, along with vitamin C and fiber. However, women with kiwi allergies or those on certain medications should consult their healthcare providers.

5. Can kiwi help with constipation?

Yes, studies have shown that consuming 2-3 kiwis daily can significantly improve constipation symptoms. This effect is attributed to its fiber content, actinidin enzyme, and other compounds that support digestive health.

6. How can you tell if a kiwi is ripe?

A ripe kiwi yields slightly to gentle pressure without being mushy. Unripe kiwis are firm and sometimes sour, while overripe ones are very soft and may have a fermented smell. To speed ripening, place kiwis in a paper bag with an apple or banana.

7. Is golden kiwi healthier than green kiwi?

Both varieties offer excellent nutrition. Gold kiwi generally contains more vitamin C and is higher in antioxidants, while green kiwi may have more fiber. Gold kiwi also tends to be sweeter and less acidic, making it preferable for those with sensitive digestion.

8. How long do kiwis last in the refrigerator?

Ripe kiwis will last 1-2 weeks in the refrigerator. Unripe kiwis should be left at room temperature until they yield slightly to pressure, then refrigerated to extend their life.

9. Is kiwi acidic or alkaline?

Kiwi is acidic in its natural state with a pH of around 3.1-3.96, similar to oranges. However, after digestion, it has an alkalizing effect on the body due to its mineral content, particularly potassium.

10. Can I eat kiwi if I have acid reflux?

Some individuals with acid reflux may experience worsened symptoms after eating acidic fruits like kiwi. If you have GERD or acid reflux, you might want to test your tolerance with a small amount first and consider consuming it with a meal rather than on an empty stomach.

11. Can children eat kiwi?

Yes, kiwi is generally safe for children over 6 months old (when introducing solid foods). However, due to the potential for allergies, it’s recommended to introduce it gradually and watch for any adverse reactions. For young children, peeled and mashed or cut into small pieces is safest to prevent choking.