The properties of the kiwi
All the benefits of a precious superfood
When discussing the properties of kiwi fruit, two main ones can now be considered well-established: the effect on bowel regularity e its vitamin C content. Yes, it's definitely worth calling this fruit a “superfood”. Let's start from the origins, and then delve into one of the properties of kiwi that makes it particularly appreciated and known: its effect on intestinal regularity. Constipation is a common problem, so much so that in the Western population it is estimated to affect up to 24% in elderly people, particularly among women. In cases of constipation, general measures are recommended such as increasing water intake, dietary fibre, and the use of laxatives. A diet with a sufficient amount of fibre (20-35 g per day) helps to form soft, bulky stools. Whole kiwis have been used and promoted for many years to maintain adequate abdominal comfort. Components present in kiwi have been shown to increase stool mass and softness. It is thought that the combination of soluble and insoluble fibres, polyphenols, and in particular a molecule called Actinidine, confer benefits to the gastrointestinal tract, reduce abdominal discomfort, both in individuals with irritable bowel syndrome and in healthy people suffering from constipation. It is known that Fibre in kiwi fruit is about 3.4 g/100 g, demonstrating it to be a good source of dietary fibre. Furthermore, one of the substances found in kiwi that has been seen to interact in promoting regular transit is precisely actinidin, a proteolytic enzyme. Recent studies have shown that Actinidin aids protein digestion both in the stomach and in the small intestine. All of this suggests that the enzyme may aid protein digestion, thus also benefiting individuals with impaired digestive function.
The benefits of kiwi in the daily diet
It has been found that daily consumption of two kiwifruits increases frequency, reduces gastrointestinal transit time, and improves measures of bowel comfort. Indeed, The kiwi promotes a prebiotic effect, that is, to support our gut microbiota, promoting the content of lactobacilli and bifidobacteria, as long as the fruit is consumed. The effect was seen to vary from individual to individual. Kiwis are a good dietary source of plant-derived molecules. with antioxidant action, as we already know, among all Vitamin C. The daily consumption of two kiwis for four weeks improves antioxidant capacity in subjects with hyperlipidemia, i.e. a suboptimal lipid profile. It has been observed how weekly kiwi consumption is correlated with improved blood lipid profiles and to reduced cardiovascular risk. This leads to the conclusion that the properties of kiwi may play a role in the management of some chronic-degenerative conditions, such as diabetes, particularly type 2, whose causes are more attributable to lifestyle and eating habits. Green kiwi and the Yellow kiwi They have respective glycaemic indices (GI) measured at 39 and 48, placing them in the low glycaemic index (GI < 55) food category. The glycaemic response to a fruit depends not only on its glycaemic index but also on the amount of carbohydrates it contains. Since The kiwi contains only about 12% carbohydrates available and a low GI, the impact that kiwi has on blood glucose levels is low, so much so that it is tolerated by people with insulin resistance or, worse, diabetes. The fibre content of kiwi can also cause a delay in carbohydrate absorption, through a swelling action that reduces the speed of sugar diffusion. This is due to the fact that The fibres contained in kiwi fruit have a good capacity to retain water. When these are ingested, the fibres contained in the kiwi retain water, swelling and thickening, acquiring a gelatinous consistency. As the meal is digested, food is broken down into simpler sugars, which move more slowly along the gelatinous substance formed by the fibres. In this way, Sugars are absorbed slowly into the blood and the energy is released more gradually. It has been shown that Consuming three kiwis a day for 3 weeks improves blood pressure, as well as antithrombotic effects in middle-aged and elderly male smokers.
The antioxidant properties of kiwi
The presence of antioxidant components such as vitamin C, vitamin E, and polyphenols, along with a favourable sodium-to-potassium ratio, could explain the beneficial physiological effects associated with the fruit. This significant intake of antioxidants makes kiwi consumption interesting from a more “dermocosmetic” perspective as well, for example, aimed at combating acne. Reinforcing this hypothesis, the high quantity of Alpha-hydroxy acids, substances with strong exfoliating properties, widely used in cosmetics and of which kiwi is particularly rich. The function of the Alpha-hydroxy acids is that of Improve the skin's appearance 360 degrees, addressing impurities, blemishes and wrinkles, deeply nourishing the dermis and promoting collagen production. Vitamin C then seems to further enhance the effect of alpha-hydroxy acids, and is itself involved in collagen regeneration processes. In Kiwi, we also find a good amount of Vitamin A, which can also perform an antioxidant and toning action, being a treatment of choice for combating acne. Furthermore, The kiwi protects from UV rays thanks to Vitamin E, an antioxidant that counteracts the appearance of skin spots and blemishes due to sun exposure, environmental pollution or bad habits such as smoking.
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