Kiwifruit is one of the fruits that has a lot of health benefits and everyone who eats them must be aware of them.
The common health benefits of kiwifruit include aiding digestion, controlling blood pressure, being good for asthmatics, aiding in wound healing, giving healthy skin, boosting immune function, and thus preventing diseases.
In this post, you will learn a lot about the top health benefits of kiwifruit and appreciate why you should be eating them.
What is Kiwifruit
Kiwifruit belongs to the genus Actinidia, a group of plants characterized as functional dioecious, deciduous, or semi-deciduous, or evergreen woody vines. The genus comprises 54 species.
Over 90% of global kiwifruit production is concentrated between China and other countries. According to O’Rourke (2012), around two-thirds of global kiwifruit production is exported, with Italy, New Zealand, and Chile as the world’s leading exporters of kiwifruit.
Other countries, among the top ten producers of kiwifruit, are France, Greece, Japan, the United States of America, Iran, and Spain. Since kiwi is grown in many different locations, the fruit can be in season throughout the year.
Kiwi can also be found in supplement form.
How did the fruit get its name
In the mid-1930s, the domestic market for kiwifruit began in New Zealand with commercial exports made from the country in the 1950s, and was popularly known as “Chinese Gooseberries”.
The idea to rename the fruit is credited to Frieda Caplan, owner of Frieda’s Finest Produce Specialities, a Los Angeles-based specialty produce store, which was among the first to import the fruit into the United States.
With its brown furry skin, which resembled New Zealand’s iconic native bird the kiwi, Frieda suggested New Zealand growers rename the fruit “kiwifruit” to get a better marketing response.
Following this, the New Zealand fruit marketer Turners & Growers adopted this name, and since then the name kiwifruit has achieved general acceptance across commercial, scientific, and technical fields, as described by Ferguson and Bollard (1990).
Of the many different species of kiwifruit, Actinidia chinensis var. chinensis (golden kiwi) and A. chinensis var. deliciosa (Chinese gooseberry) are the most important species for commercial cultivation.
Other species of the kiwifruit include red kiwi (A. melanandra), two species with resistance to cold (A. arguta and A. kolomikta), purple kiwi (A. purpurea), chinese egg gooseberry (A. coriacea), red kiwi (A. melanandra), silver vine (A. polygama), A. latifolia
Kiwis are typical berry fruits containing many distinctive small black seeds arranged in rows in the flesh (mesocarp).
They usually possess hairy skins with a few being glabrous. The edible parts are the mesocarp (flesh) and placenta; the seeds can also be consumed.
How does Kiwifruit look like
Fruit size is usually 20-70g, maximum up to 200 g, or even larger. Fruit shapes are quite different for various species and varieties, but mostly oval, oblong, flat round, and cylindrical.
The flesh color may be green, brown, orange, red, purple, yellow, or red. Ripen fruits have high soluble solids content, soft texture, special flavor, and moderately sweet or sour (astringent) taste.
Potential health benefits of kiwifruit
A key element to increasing the global consumption of kiwifruit is understanding the health benefits of kiwifruit and explaining these health benefits to current and future potential consumers to drive demand.
Kiwifruit is proven to be one of the most nutrient-dense fruits available. It has a broad range of vitamins and minerals. Kiwifruit is exceptionally high in vitamin C, and also contains dietary fiber, potassium, folate, and vitamin E, as well as scoring low on the glycemic index [9].
Another important aspect of the health benefits of kiwifruit has been the kiwifruit proteolytic enzyme, actinidin, which aids in digestion and gut health, especially in those with constipation.
The whole herb, including the root, is used as an anti-inflammatory and an anti-swelling analgesic to treat sore throat, diarrhea, rheumatoid arthritis, boils, and pyodermas.
The nutrients in kiwi may be useful to humans in the following ways
Kiwifruits gives you a healthy skin
On a fresh weight basis, kiwifruit contains about 1-2 times more vitamin C than an orange, 10 times as much as a banana, and up to 15 times as much as an apple. Only a few readily available fruits, such as blackcurrants or guavas, are richer in vitamin C.
A typical A. chinensis var. deliciosa kiwifruit contains about 85mg ascorbate/100g FW, a fruit of A. chinensis var. chinensis up to 30% more, about 105-11- mg ascorbate/100g FW [9].
The USRDI recommended daily intake for vitamin C is currently 90 mg for an adult male and 75 mg for an adult woman with higher levels recommended for smokers or lactating mothers.
One average-sized kiwifruit could by itself, therefore, provide the daily intake recommended for the general population, if allowance is made for the oxidized form of ascorbic acid, dehydroascorbic acid, possibly being not biologically effective.
Studies indicate that a daily intake of 200-400 mg/day will saturate both plasma and body tissues.
In terms of vitamin C, there is probably little advantage in consuming more than two or three kiwifruits in a day.
Vitamin C is needed for the synthesis of collagen and is involved in protein metabolism in the body. Collagen is an essential component of connective tissue in body structures such as the skin, which plays an essential role in wound healing.
Vitamin C is an important physiological antioxidant and has been shown to regenerate other antioxidants within the body, including alpha-tocopherol (vitamin E) [14][25].
Kiwifruit also provides vitamin E (alpha-tocopherol). Vitamin E is also an important physiological antioxidant and has a beneficial role in protecting the skin from sun damage.
Kiwifruits protects and preserve your digestive health
One of the health benefits of kiwifruit is that it is able to protect and preserve your digestive system.
Polyphenols in kiwifruit reaching the colon may directly stimulate the growth of beneficial bacteria or act as antimicrobial agents that protect against pathogens in the gut. It contains the proteolytic enzyme, actinidin, which helps break down proteins in the diet.
Nondigestible polysaccharides fermented by the microorganisms in the gut may induce selective growth of beneficial bacteria [17][4].
Clinical studies in a range of adult populations consistently indicate that kiwifruit is a highly effective dietary option to promote laxation.
Thus, in constipated individuals, kiwifruit consumption results in relief from constipation due to significant reductions in colonic transit times, improvements to stool form and volume, along with increased ease, and satisfaction of defecation.
Cardioprotective effects and management of blood pressure
Platelets are involved in the atherosclerosis process, and therefore, reduction of platelet activity decreases the incidence of cardiovascular diseases in diabetics, smokers, and people suffering from metabolic syndrome.
Both in vitro and human studies indicate that both green and gold kiwifruit have cardio-protective effects. Consumption of kiwifruit (green and gold) lowered the platelet aggregation response in both healthy human volunteers and smokers.
Consumption of kiwifruits also reduced levels of triglycerides in plasma, with no effect on cholesterol levels.
Effects of kiwifruits on platelets and blood plasma lipids are reversible as platelet aggregation responses and lowering effects on plasma triglyceride disappeared during the washout period.
Two other fruits/vegetables that have been found to have similar cardiovascular benefits are jackfruits and garlic.
Kiwifruit and mineral nutrition
Kiwifruit is a nutrient-dense food, containing nutritionally significant amounts of several key micronutrients compared with other fruits.
Kiwi contains an array of important nutrients including iron, calcium, magnesium, copper, folate, and potassium, as well as vitamins A, B6, C, and E.
Iron is needed for hemoglobin synthesis, the red blood cell protein responsible for transporting oxygen from the lungs to the body’s tissues. Much of the remaining iron is found in myoglobin, a protein important for storing oxygen in muscle tissue.
Anemia, fatigue, decreased immune function, and reduced physical work capacity is commonly associated with iron deficiency [16].
The body’s magnesium content is nearly 10 fold that of iron. Over half of the body’s magnesium is located in the bone, where it forms complexes with calcium and phosphorus [3].
The remainder is mainly in muscle tissue and is found within the cells [24].
Magnesium deficiency may cause tachyarrhythmia, depression, reduced calcium levels as well as bone diseases such as impaired growth and osteoporosis [2]
Calcium, like magnesium, is largely stored in bone and is a crucial structure of bone [3]. In children and young adults, dietary calcium intake is essential for the achievement of peak bone mass [5].
Bone mass declines with aging and is worsened by the fact that dietary calcium levels are often deficient in the elderly, leading to poor skeletal diseases including osteoporosis [22].
Accurate maintenance of blood calcium is also required for the regulation of blood pressure and cardiac function, severe deficiency in calcium can result in muscle spasms and an abnormal rate of muscle contractions in the heart.
Potassium is the main ion inside cells and regulates key processes such as the transport of ions, thereby maintaining the osmolarity of cells and blood pressure [12].
Low body potassium results in muscle weakness and failure to maintain blood pressure. High body levels of potassium will cause renal failure [21].
Kiwifruits and Human Immunity
There is no convincing evidence that kiwifruit can modulate immune responses in a way that would be beneficial to the host. Kiwifruit contains vitamin C, carotenoids, polyphenols, and dietary fiber, and these are all potentially beneficial to the immune system.
In vitro studies using cell lines and human blood cells, to using animal models targeting both mucosal and systemic immunity have contributed to our understanding of the beneficial effects kiwifruit may have on immune responses.
Some limited human intervention trials have been undertaken and described.
In these trials, kiwifruit has been shown to influence a number of biomarkers of oxidative stress and beneficial immune responses, to reduce the incidence and severity of symptoms of upper respiratory tract infections such as cold and influenza and potentially more beneficial than supplementation with vitamin C alone.
Modulator of DNA damage and DNA repair reducing risk of other health conditions
Kiwifruit has proved to be a valuable test material for investigations into antioxidant effects in humans.
They have also revealed unsuspected influences of phytochemicals on DNA repair, suggesting a protective role; decreasing DNA oxidation damage and enhancing the removal of the damage that nevertheless does occur.
These potential effects of kiwifruits in reducing oxidative stress can prevent certain health problems [7].
Benefits of Kiwifruits in Pregnancy
One of the most important health benefits of kiwifruit in pregnant women is the provision of folic acid.
Folic acid is necessary for cell division and thus important during pregnancy as it may protect the developing fetus from problems such as neural tube defects. Kiwifruits are often referred to as being a good source of dietary folate.
What are the nutritional contents of Kiwifruits
Kiwifruit contains nutritionally significant amounts of several key micronutrients often found to be deficient, even in high-energy Western diets. Below is a table showing the mineral content and percentage of Recommended Daily Intake (RDI) or Adequate Intake (AI) in kiwifruit
| Mineral | mg/100 g gold kiwifruit+ | mg/100 g green kiwifruit+ | RDI or AI* (mg/day for adults aged 19-50) | RDI/100 g kiwifruit (%) |
| Iron | 0.29 | 0.31 | 18 (Women) 8 (Men) | 2-4 |
| Calcium | 20 | 34 | 1000 | 2-3 |
| Magnesium | 14 | 17 | 310-320 (Women) 400-420 (Men) | 3-5 |
| Copper | 0.15 | 0.13 | 1.2 (women)* 1.7 (Men)* | 8-12 |
| Potassium | 316 | 312 | 2800 (Women)* 3800 (Men)* | 8-11 |
| Manganese | 0.06 | 0.10 | 5.0 (Women)* 5.5 (Men)* | 1-2 |
| Phosphorus | 29 | 34 | 1000 | 3 |
| Zinc | 0.10 | 0.14 | 8 (women) 14 (Men) | 1-2 |
| Selenium | 0.003 | 0.0002 | 0.06 (Women) 0.07 (Men) | ≤ 1 |
| Vitamin C | 105 | 93 | 45 | 206-234 |
| Vitamin E | 1.5 | 1.5 | 7 (Women)* 10 (men)* | 15-21 |
| Vitamin K | 0.006 | 0.04 | 0.06 (Women)* 0.07 (Men)* | 8-67 |
| Folate | 0.034 | 0.038 | 0.4 | 9 |
Adapted from USDA database (except folate)
+ Gold kiwifruit: A. chinensis var chinensis
+ Green kiwifruit: A. chinensis var deliciosa
What are the health risks associated with eating Kiwifruits
Allergy
While kiwifruit has a high nutritive and health value, a small proportion of the world’s population appears to be allergic to the fruit.
IgE-mediated kiwifruit allergy is often associated with birch and grass pollinosis as well as with latex allergy. Isolated allergy to kiwifruit is also relatively common and often severe.
The majority of allergic reactions to kiwifruit occur within minutes of consuming a kiwifruit or kiwifruit-containing food product.
Symptoms involved in oral allergy syndrome are:
- Swelling and itching of the lips, tongue, and pharynx
- Pruritus of the eyes, ears, tongue, pharynx, and mouth.
More severe symptoms such as urticaria, abdominal pain, moderate dyspnea, rhinitis, cyanosis, or anaphylaxis occur in 18–46% of kiwifruit-allergic patients [1]
Interaction with certain orthodox medications
People treated for cardiovascular disease or at risk may be prescribed anticoagulants (blood thinners). Kiwi contains Vitamin K, which can interfere with the action of anticoagulants such as warfarin
People taking drugs such as spironolactone, or angiotensin-converting enzyme inhibitors (e.g. Lisinopril), angiotensin receptor blockers (e.g. losartan) may be exposed to the toxic effects of high potassium if their dietary intake of potassium is in excess.
The situation is worsened in people with kidney problems who are not able to remove excess potassium from the blood.
Thus you have to speak to your pharmacist or doctor if you have any of such conditions and still want to consume kiwifruits.
WRITTEN AND EDITED RESPECTIVELY BY:
Dr. Solomon Kwesi Otchere (Pharmacist)
Dr. Solomon Kwesi Otchere is a Pharmacist by profession in Ghana. He is passionate about informed healthy lifestyle and diet options necessary for preventing many disease conditions. He also empowers patients and clients to make savvy choices on medications needful to promote good health.
Dr. Ehoneah Obed is a registered pharmacist and a member of the Pharmaceutical Society of Ghana. He has a Doctor of Pharmacy degree from Kwame Nkrumah University of Science and Technology and has experience working in a Tertiary hospital as well as various community pharmacies. He is also a software engineer interested in healthcare technologies.
His love for helping others motivates him to create content on an array of topics mostly relating to the health of people and also software engineering content.
He is knowledgeable in digital marketing, content marketing, and a host of other skills that make him versatile enough to uplift any team he joins.
Enno Obour Nkansah
Enno Obour Nkansah is a Certified Medicine Counter Assistant (MCA) who has practiced as an MCA for three years. She is currently a student at Korle-Bu school of hygiene and is passionate about improving the health and wellbeing of people.
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