Kiwis improved your mood in just four days
The benefits of kiwifruit, a tropical plant of the actinidia family, are well known. It is a source of vitamins C, B, K, antioxidants and dietary fiber. Past experiments have shown that eating kiwi improves mood and boosts energy. Now, a randomized placebo-controlled trial has found that positive effects can occur in as little as four days.
Kiwi fruit is the champion of vitamin C content. Gold kiwi ("golden" or "yellow" kiwi) is especially rich in it, which satisfies the daily requirement for ascorbic acid by 200%.
Scientists know that vitamin C deficiency in the body correlates with mood depression and cognitive impairment. Conversely, including ascorbic acid supplements or foods in the diet is associated with improved mood, vitality, well-being, and decreased depression. However, the question of how quickly this action can be achieved in people with vitamin C deficiency has been less studied. New Zealand researchers decided to fill the gap.
To do this, Professor Tamlin Conner (Tamlin Conner) from the University of Otago (New Zealand) together with colleagues from his university and the University of Auckland organized an experiment. It involved 155 subjects from 18 to 35 years old with reduced plasma levels of vitamin C (less than 40 micromoles per liter).
The volunteers, 63% of whom were women, were divided into three groups. For eight weeks, participants in one received daily vitamin C - 250 milligrams in the form of a chewable tablet, another received a placebo, and the third received two kiwis of the SunGold kiwi variety.
In addition, using smartphones, the participants took a survey every other day in which they rated their vitality, mood, psychological well-being, sleep and physical activity. The subjects also had their plasma vitamin C concentrations measured every two weeks.
Laboratory analyses showed that taking ascorbic acid and eating kiwi allowed to saturate the body with vitamin C in two weeks. At the same time, the subjects whose diet included kiwi felt the positive effect on vitality and mood after only four days. Sustained daily effects occurred on days 14-16. By the same time, scores of psychological well-being had increased.
In the group that took ascorbic acid in tablets, the participants' moods improved perceptibly only from day 12 of the study.
Using the iAUC (incremental Area Under Curve) method, the researchers found that kiwifruit improved the subjects' vitality and mood more strongly than taking ascorbic acid pills compared to placebo. Admittedly, this effect did not persist after adjusting for covariates.