Kiwi fruits may be small but they’re mighty in flavor and health benefits. Their sweet and tangy green flesh contains essential nutrients like vitamin C, vitamin K, vitamin B6, riboflavin, niacin, folate, and potassium. Plus, they’re a great source of antioxidants and carotenoids, like vision-enhancing lutein and zeaxanthin, as well as a fair share of dietary fiber. Let’s delve into the most important kiwi fruit nutrition facts, plus the truth about how kiwi’s sugar content compares to that of other fruits.
A Little Kiwi History
Before these fuzzy fruits became a national treasure of New Zealand, they were cultivated in northern China. The Chinese Gooseberry, as it was known at the time, was only imported to New Zealand in the early 1900s, when cultivation began. To avoid the taxes on exported berries, the name was changed to kiwifruit, which is fitting as it is tiny, brown, and fuzzy, just like New Zealand's national symbol, the kiwi bird.
It wasn't until 1968 that the name was shortened to kiwi, courtesy of a fruit-packaging firm, and today the kiwi is cultivated around the globe, from China to South Africa, Chile, and Japan.
5 Kiwi Fruit Nutrition Facts to Know
According to the United States Department of Agriculture (USDA) National Nutrient Database, the average kiwi contains:
- 42 calories
- 0.4 grams of total fat
- 0.8 grams of protein
- 6.2 grams of sugar
- 2.1 grams of fiber
- 64 milligrams of vitamin C (107% of your recommended daily value (DV))
- 8 micrograms of vitamin K (35% of your DV)
- 17 micrograms of folate
- 7 milligrams of magnesium
- 23 milligrams of calcium
- 215 milligrams of potassium
- 1 milligram of vitamin E
- 60 international units of vitamin A
Here are five of the most exciting facts you should know about the nutritional benefits of kiwi fruit consumption.
1. Kiwi and Vitamin C
Research shows that thanks to their high vitamin C content, kiwis have numerous health benefits. In addition to acting as an immune-system strengthener, vitamin C plays an especially important role in collagen synthesis. Collagen provides structural integrity to the skin, and the benefits of eating vitamin C-rich fruits like kiwi include protecting your skin from damage caused by UV light, pollution, and smoke, as well as improving overall skin texture.
2. Kiwi and Vitamin K
Kiwi is a good source of vitamin K, which helps to maintain the health of your bones, brain, and heart. Without adequate intake of vitamin K, your body cannot produce a substance called prothrombin that plays critical roles in blood clotting and bone metabolism, protecting you against both heart disease and osteoporosis.
3. Kiwi and Potassium
Many people are deficient in potassium, which functions as both a mineral and an electrolyte inside the body. We need potassium to maintain normal blood pressure by relaxing the blood vessels, and to transport nutrients to our cells and preserve healthy nerve and muscle function.
4. Kiwi and Fiber
Research findings show that kiwi fruit can improve digestion, particularly for individuals with irritable bowel syndrome. One reason for this may be kiwi’s fiber content—1.7 grams per kiwi! Kiwis are also an excellent source of actinidin, a proteolytic enzyme that helps break down protein and improve digestion.
5. Kiwi and Antioxidants
Kiwi fruit contains a wealth of polyphenols shown to have powerful antioxidant effects. Antioxidants help neutralize scavenging free radicals that instigate the oxidative stress behind premature aging and chronic disease. Studies show it has even more potent antioxidant activity than oranges and grapefruits do, and can help prevent the development and deterioration of diseases known to be linked to oxidative stress.
What About Kiwi Seeds?
You know those teeny-tiny kiwi seeds that love to get stuck between your teeth? They're doing more than just being annoying. They're offering up a little extra protein, vitamin E, fiber, and omega-3 fatty acids for heart health and brain health.
Worried About Kiwi Sugar Levels?
Kiwi’s sweet flavor might cause worry that it’s a high-sugar fruit, which in turn might make you worry it’s not a healthy fruit option or could sabotage your weight-loss efforts. But as you can see from the kiwi fruit's nutritional value discussed above, the average sugar content is about 6 grams.
As a point of comparison, a medium navel orange contains 14 grams of sugar while a red delicious apple contains 16 grams of sugar. Don’t let concerns about sugar keep you from eating deliciously sweet and juicy kiwis—you can have two for the same amount of sugar found in apples and oranges!
So, why is the kiwi GI listed as 52, putting it on the average to high end? The glycemic index was one of the first methods developed to measure how sugary foods are, but it has some design flaws. A big one is that it doesn’t account for standard serving sizes, instead standardizing each food entry to contain 50 grams of carbohydrates. To give some context for the problems that creates, 50 grams of carbs in the form of a Snickers bar translates to a petite 2.8-ounce serving, while 50 grams of carbs in the form of pumpkin necessitates a whopping 35-ounce serving, far more than the average individual is likely to eat in one seating.
To help correct these distortions, researchers at Harvard University introduced the concept of the Glycemic Load in 1997. And the kiwi glycemic load is just 7, well below the threshold set at 11 for low glycemic load foods, so the affects on your blood sugar shouldn't be substantial, especially with the soluble fiber in kiwi lending a helping hand.
What Type of Kiwi Are You Eating?
Chances are you're eating the fuzzy-brown green Hayward kiwi, or Actinidia deliciosa, the most common variety of kiwi fruit.
If you're lucky enough to run across a gold kiwi, bronzed with a pointed tip, mustard-colored innards, custardy texture, and sweetly sour flavor, grab it and go!
You might have also seen baby kiwis or grape kiwis at your local farmers market or grocers. These come from the Hardy species of kiwis and are designed to thrive in colder temperatures. Just pop them in your mouth whole, skin on.
The kolomikta kiwi, nicknamed the Arctic kiwi because it, too, can withstand cold temps, has 10 times more vitamin C than a Hayward kiwi, so swap them out during cold season if you can!
And here's the even better news: kiwis are available year round! Kiwis from New Zealand and Chile are harvested in the spring, while California kiwifruit is harvested during the winter.
How to Add Kiwi Fruit to Your Diet
You can, of course, eat kiwi fruit raw—we love it tossed in a fruit salad. And while most people remove the fuzzy skin, it’s actually entirely edible and can triple your fiber intake. But our favorite way to eat kiwi is to toss it in a blender and whip up a delicious kiwi smoothie.
And if you're not yet ready to eat the kiwi you bought, simply store it at room temperature. If it ripens quickly and you're still not ready for it, then transfer it to the refrigerator so it keeps.