Kiwifruit and Warfarin

The kiwifruit, a berry commonly associated with New Zealand, is a small fruit that contains a lot of vitamins and minerals important to our health. Kiwifruits are a “nutrient-dense” food, meaning that the fruit is high in nutrients and low in calories per serving.1 Eating these fruits can be a healthy addition to your diet, but warfarin patients should be aware that kiwifruits are high in vitamins, including vitamin K.

The Kiwifruit

Despite the kiwifruit’s popularity in New Zealand, the fruit has origins in China where it was called the Chinese Gooseberry.1,2 In ancient times, the kiwifruit was prized for various medicinal properties and may have found its way to New Zealand at the beginning of the 20th century through missionaries. Once there, the fruit was so enjoyed that it was commercially cultivated. Due to the high duties charged on berries, people instead used the fruit’s nickname, kiwifruit. The nickname, given because of the fruit’s resemblance to New Zealand’s national bird the kiwi, stuck and the fruit was then called kiwifruit.1,2

The kiwifruit contains a lot of power in its small, brown and fuzzy form. The tangy green flesh contains vitamin C, vitamin E, folate, potassium, antioxidants and fiber.3 Every part of the kiwifruit is edible, including the small black seeds and fuzzy brown peel, although most people will use the peel as a bowl to scoop out the green fruit. Having a large variety of fruits and vegetables within your diet can be associated with a reduced risk of developing sicknesses like heart disease, diabetes and cancer as well as conditions such as obesity.1 Some of the different nutrients that kiwifruit can be a good source for include:

  • Vitamin C: Kiwifruit is a great source of vitamin C. Each 100 grams of kiwifruit contain about 154% of the daily recommended value. The percentage is almost twice that of lemons and oranges.2 Vitamin C helps your immune system as well as your skin.
  • Fiber and Actinidain: Actinidain is a type of enzyme found in kiwifruit that helps the body digest proteins. Combined with amount of fiber found in the fruit, the kiwifruit can help you with digestion.2,3
  • Potassium: Potassium can not only help with digestion, but it can also support your heart health.1

The kiwifruit has also been known to help people who have trouble sleeping or have sleep disorders. Studies have shown that having kiwifruit before bed can improve your sleep.1 It has been found that having two kiwifruits one hour before bedtime can help to induce sleep.2

Kiwifruit and Warfarin

While kiwifruit is a good addition to dishes like salads and desserts, the little berry is a fruit that warfarin patients need to consider. One fruit of the popular green kiwifruit, approximately 69 grams, contains a high amount of vitamin K of about 27.8 micrograms.4 A variety of kiwifruit, the golden kiwi, is different. One fruit of golden kiwi, around 81 grams, contains a low value of vitamin K at about 4.9 micrograms.4 Knowing the type of kiwifruit you are consuming is a good practice for patients concerned with Vitamin K level. It has been shown that eating two to three kiwifruits a day can lower your risk of blood clotting.3

Remember that when it comes to your diet and warfarin, consistency is the most important practice. Before you add anything new to your diet, make sure to follow-up with your treating physician. 

References:

  1. Ware, M. RDN, LD. Kiwifruit: Health benefits and nutritional information. Medical News Today. June 20, 2017. Retrieved from the website: http://www.medicalnewstoday.com/articles/271232.php.
  2. Borah, P. 7 Kiwi Fruit Benefits: From Powerhouse of Antioxidants to Inducing Sleep. Smark Cooky. July 13, 2017. Retrieved from the website: http://food.ndtv.com/food-drinks/7-kiwi-fruit-benefits-from-a-powerhouse-of-antioxidants-to-inducing-sleep-1236599.
  3. Gotter, A. 7 Health Benefits of Kiwi. Healthline. December 14, 2016. Retrieved from the website: http://www.healthline.com/health/7-best-things-about-kiwi#overview1.
  4. US Department of Agriculture, Agricultural Research Service, Nutrient Data Laboratory. USDA National Nutrient Database for Standard Reference, Release 28. Version Current: September 2015, slightly revised May 2016. Internet: /nea/bhnrc/ndl.