Over a six-week period, normally-healthy young men either ate two kiwifruit a day or half a kiwifruit daily as part of a research study into the potential mood-enhancing effects of the fruit.
Researchers found those eating two kiwifruit daily experienced significantly less fatigue and depression than the other group. They also felt they had more energy. These changes appeared to be related to the optimising of vitamin C intake with the two kiwifruit dose. Kiwifruit are an exceptional source of vitamin C.
The findings were published recently in the Journal of Nutritional Science. The study was carried out with 54 young male university students who generally eat little fresh fruit and whose vitamin C levels are lower than desirable due to this.
Professor Margreet Vissers and her team from the UOC’s Centre for Free Radical Research are involved in a large on-going study to better understand the critical role of vitamin C in the human body.
Professor Margreet Vissers
Professor Vissers says “the two kiwifruit per day ensured that the study group’s vitamin C levels were optimal, and this was needed to see an effect on mood and energy. The amount of vitamin C required for this is higher than the current recommended intake. Our study provides good evidence to support the view that there are measureable health benefits to be obtained from eating a good amount of fruit and vegetables daily. For best benefit, it is important to include high vitamin C foods in your daily diet.”
Vitamin C helps activate a number of enzymes in the body that enhance the levels of metabolic energy and different neurochemicals in the brain, Professor Vissers says. This means taking in more vitamin C could decrease feelings of fatigue and increase physical and mental energy.
This work was funded by the Ministry of Business, Innovation and Employment as well as the University of Otago and Zespri International.
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