Kiwifruit has better vitamin C than a pill
Kiwifruit is a better source of vitamin C (ascorbate) than purified supplements – at least for mice, University of Otago in Christchurch researchers have found.
Kiwifruit
Food provides macronutrients and micronutrients. Kiwifruit is a good source of vitamin C – a micronutrient that is essential for health and wellbeing and the kiwifruit enzymes help digestion.
In the study, some mice were fed ascorbate via their drinking water and others were fed on fresh pulped kiwifruit for 1 month. Tissue samples from the mice were then measured for their vitamin C content and compared with each other and also with tissue samples from wild-type mice with no treatment.
The researchers found that, in mice eating kiwifruit, vitamin C uptake was 5 times as effective as in those given a purified supplement form. The mice absorbed the vitamin C more efficiently and retained it in their systems for longer.
This has led the researchers to suggest that there is a component in the kiwifruit that improves absorption and retention of vitamin C. The mouse study was recently published in The American Journal for Clinical Nutrition, the highest-ranking journal for human nutrition research. In their paper, the researchers conclude that “it is possible that the bioavailability of ascorbate is superior from some foods, such as kiwifruit. These results have important implications for human nutrition.”
The research team, led by Associate Professor Margreet Vissers, has just started trials in humans to see if the same important nutritional effect occurs.
Daily requirement of vitamin C
Dr Sean Bulley from Plant & Food Research along with Carolyn Cairncross from the New Zealand Nutrition Foundation explain the importance of vitamin C in the diet. Examples of plant foods rich in vitamin C are given, and advice is offered about the efficacy of vitamin C supplementation.
Point of interest
Some nutritionists believe that the daily dose of vitamin C is best taken in by consuming a plant food, like kiwifruit, rather than in tablet form. What is the reason for this?
Although vitamin C is essential to tissue and organ health, human bodies do not make it. Instead, we rely on acquiring vitamin C from what we eat. Vitamin C is one of the most commonly taken vitamin supplements, especially in winter, but perhaps we would be better off eating more fruit. Research will tell.
Useful links
Read the abstract of the research report in The American Journal of Clinical Nutrition.
Activity idea
In relation to this news article, your students may like to investigate how vitamin C content could be improved in future fruit varieties in the article Vitamin C and the future.
