Reduce Winter Cold Symptoms with Golden Kiwi
This cold season, go for the gold--golden kiwi, that is. Several studies have shown that golden kiwi are important sources of antioxidants that can help in the fight against the common cold, including a study in the British Journal of Nutrition, which reports that elderly volunteers who ate golden kiwi daily suffered significantly less time with some cold symptoms than they did when eating bananas.
Golden kiwi are less hairy versions of green kiwi
The kiwi most people are familiar with is the fuzzy-skinned, green fruit that has a tart taste and is known for its high antioxidant content, especially vitamin C. Now picture a much less hairy kiwi with golden fleshy pulp and less tart taste and you have the golden kiwi (Actinidia chinensis).
The golden kiwi is a new cultivar developed in New Zealand. Like its greenish cousin, the golden kiwi is an excellent source of vitamin C and a good source of vitamin E (alpha-tocopherol), potassium, fiber, and the carotenoids lutein and zeaxanthin. The tiny black seeds in kiwi can be crushed to release their oil, which is very rich in alpha-linoleic acid (an omega-3 fatty acid).
Golden kiwi and the common cold
In the new study, 37 healthy older adults (older than 65 years) were asked to consume 4 golden kiwi daily for 4 weeks, followed by four weeks during which they did not eat kiwi or bananas, then four weeks during which they ate 2 bananas daily.
At the end of the study, the volunteers reported that they has a significant reduction in how long they experienced certain cold symptoms when eating kiwi compared with when they ate bananas.
Specifically, there was a significant reduction in head congestion symptoms (from 4.7 to 0.9 days, respectively) and sore throat (from 5.4 to 2 days, respectively). The volunteers also reported an easing in severity of head congestion symptoms when they ate kiwi as compared to when they ate bananas.
During an infection, such as the common cold, vitamin C levels decline dramatically, and this vitamin is necessary for healthy immune system function. In this study, the authors noted that consuming the golden kiwi resulted in an increased level of vitamin C in the volunteers’ blood.
In a study by researchers at the US Department of Agriculture’s Arkansas Children’s Nutrition Center, kiwi were compared with red grapes and strawberries for their antioxidant powers. The experts found that kiwi were more easily used by the body than were the other two fruits, both of which are typically valued for their antioxidant abilities.
An estimated 62 million cases of the common cold occur each year in the United States, according to the National Institute of Allergy and Infectious Diseases. Children are more likely to develop a cold (6-10 per year) than are adults, who typically have 2 to 3 per year.
According to the study’s lead author, Dr. Denise Hunter, of the New Zealand Institute for Plant and Food Research Limited, “This study shows that micronutrients provided by regular eating of golden kiwifruit appears to be important in reducing symptoms of colds and other upper respiratory infections.” Kiwi anyone?
(This article was updated on January 8, 2013)
Hunter DC et al. British Journal of Nutrition 2011; doi: 10.1017/S0007114511006659
Kiwi fruit: antioxidant power in quantity and quality
Picture credit: Wikimedia Commons