C.as is the case with all the hugely popular themes, including the vitamins we talk about it and inappropriately. They are synonymous with health and there is no doubt that they are indispensable. But a widespread prejudice, for example, is that today’s fruits and vegetables do not contain enough. Another misconception is that the supplements have a similar effect to spinach for Popeye: take a capsule and get stronger. The fact is that in Western countries a fortune is spent on supplements and Italy is in the lead for purchases in Europe. In the UK, more vitamins are bought than painkillers, and at least half of Americans take one multivitamin.
Theories explaining the steady growth in demand for supplements include reflections on frenetic modernity, which does not give us time to eat good food, and the idea that a longer-lived population should be offered products for painless joints and eternal youth. But what do the guidelines of health institutions say? What the vitamins should be supplemented when they are deficient, while taking more than necessary will not improve the state of well-being. The other question is whether taking them in pills and sachets is bad for you. Always valid advice is to consult a doctor, blood test on the hand for check for deficits, and in any case look on the packaging of the supplements what is the recommended daily dose. To know that the vitamins such as C and those of group B are water-soluble and they cannot be accumulated by the body: any extra ends up in the urine. Instead the vitamins A, D, E and K are fat soluble, whereby the excess is stored in body fat. High levels of vitamin A can be toxic and excessive amounts of vitamin D lead to hypercalcemia, with the risk of kidney stones. But here are nine facts about vitamins.
The plum that has a hundred times more vitamin C than orange
Researchers and pharmaceutical companies have been working for some time on a small fruit that has an extraordinary concentration of vitamin C: it is acerola, which grows from Mexico to South America and other tropical areas, including India. Red and similar in appearance to a cherry, it contains segments that are reminiscent of those of the mandarin. To have the absolute primacy in the world of vitamin C, however, is the Australian plum kakadu: may have over a hundred times more than an orange. Even the kiwi and black currant citrus fruits beat, but the fact remains that a medium-sized orange almost covers the daily requirement of the immune system’s vitamin ally. The same goes for a serving of strawberries or lychees.
The jug with the juice ready? No thank you
An orange juice can ensure an excellent dose of vitamin C, which is water-soluble and therefore passes almost entirely in the citrus juice. But the vitamin is very sensitive to oxidation and is quickly damaged in contact with oxygen and exposure to light. “It is therefore important to drink the juice immediately after preparing it,” reads the team’s website Smartfood of the Ieo of Milan. “If we wait even ten minutes, the vitamin C content may already have halved. For this reason, especially at the bar, we have to ask for the oranges to be squeezed on the spot and reject, instead, the juice previously prepared in the jug. Or better yet, prefer the whole fruitin order to also eat its fiber, contained in the white parts that are often discarded ».
Super tomatoes and vitamin D.
A team of scientists has just created tomatoes with a super gene. Plants were obtained by making small changes to a gene with the “cut and sew” technique called Crispr And each tomato could provide the same amount of vitamin D as two eggs or a piece of tuna. The work stems from the collaboration between Italian researchers from the CNR and the British from Norwich, to try to make up for the vitamin D deficiency which is estimated to affect 40 percent of Europeans.
The micronutrient is crucial for the metabolism of calcium in the bones and is studied for possible anti-inflammatory activity and influence on the immune system. Meanwhile, there is an ingredient of the Mediterranean diet that abounds in Italy and that we should not miss: the Sun. Under the action of ultraviolet rays, the skin produces a sort of semi-finished product, a precursor, which will be transformed into vitamin D. From food we assimilate just 10-20 percent of the necessary, the rest in the open air. Over time, however, the skin becomes less good at synthesizing it. Better to check the values with blood tests.
Seeds and almonds in the dark
There Vitamin Ewhich is part of the vitamins with antioxidant properties, fears prolonged exposure to light and oxygen air, which cause oxidation. “For this reason, it is absolutely essential that the dried fruit, oil seeds, whole grains complete with germ and vegetable oils, are stored as much as possible in the dark and in closed containers, away from light, in cool and dry places and in any case for the shortest possible time »explain the researchers Smartfood – Ieo. “In the absence of a place that meets these requirements, better to keep them in the refrigerator“.
Full of vitamin A with a couple of carrots
The color of the carrots is due to beta-carotene, a carotenoid which the body transforms into vitamin A, which is useful for eyesight, skin, bones and the immune system. A couple of carrots cover 100 percent of the daily requirement for the micronutrient. Carotenoids are better absorbed if the carrot is cooked, because the heat softens the plant cell walls, making the substances more available. Beta-carotene is found in yellow-orange vegetables, from pumpkin to melon, from mandarin to persimmon, but also in green leafy vegetables, chilli and aromatic herbs, especially parsley and oregano.
The forgotten vitamin that the brain needs
When it comes to B vitamins, mention are made of B12 and B9 (also known as folic acid), which must be supplemented during pregnancy. But the B6 it is, in a sense, “a forgotten vitamin,” as Reem Malouf, a neurologist at the University of Oxford who has studied its effects on cognition, called it. Its effects on brain health are now being studied, as it is involved in a number of chemical reactions important for the nervous system and brain function, as well as for the immune system. Usually the necessary vitamin B6 is taken with the diet. A portion of canned chickpeas, for example, it almost covers the recommended daily intake.
Vitamin B12 deficiency if you have reflux or gastritis
Vitamin B12 is also called cobalamina because it contains cobalt, the metal with blue reflections. Our stomach plays a crucial role in its assimilation, because it produces a protein, called intrinsic factor, which makes the vitamin arrive safe and sound to the intestine, where it will then be absorbed. «A tip for those with problems like the gastritis or reflux and for those who regularly use antacid drugs is to check the levels of vitamin B12 with normal blood tests “writes the nutrition physiologist of theUniversity of Bologna Enzo Spisni in the book The magnificent 20 for your defenses (Sonzogno).
In general, after the age of fifty the organism can begin to undergo a progressive reduction of the functional capacity of the gastric mucosa, which can lead to malabsorption. It must be said that vitamin B12 accumulates in our organism and that small quantities cover the needs for many days. For example, that’s enough eat fish twice a week, or a few eggs. It is the only micronutrient though it comes in lack in a vegan dietsince its food sources are almost exclusively of animal origin. To avoid a shortage, the use of the supplements and even fortified foods, how cereals for breakfast e soy products with added vitamin B12.
With antibiotics, less vitamin K.
The microorganisms that we host in the large community that colonizes our intestines, the microbiota, help us in digestion and produce a series of metabolites or postbiotics, including some vitamins, such as K. This is why the intake of Broad-spectrum antibiotics, which eliminate both good and bad bacteria, can reduce vitamin K production. Also called phylloquinone, regulates the synthesis of some blood clotting factors and it would seem able to prevent the excess bone loss that can occur in adulthood. It can be remedied at the table. They have a high content of it green leafy vegetables such as lettuce and the cabbage family. The vitamin is also in: asparagus, kiwi, avocado, pistachios, pumpkin seeds, peas, soy, egg yolk, whole grains, canned tuna.
The record for frozen spinach
Cooking and freezing do not affect the vitamin K content in food. For instance, a pound of frozen spinach covers the daily requirement of the vitamin. Beta-carotene also resists, which the body converts into vitamin A. The freezer instead depletes folate (or vitamin B9) and vitamin C.
Eliana Liotta (photo by Carlo Furgeri Gilbert).
Eliana Liotta is a journalist, writer and science writer. On iodonna.it and on the main platforms (Spreaker, Spotify, Apple Podcast and Google Podcast) you will find his podcast series The good that I want.
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