Now the market is full of all kinds of health care products under the banner of antioxidants, claiming that as long as you take these products containing vitamin E or vitamin C every day, you can maintain youth, avoid the onset of cancer and heart disease, and it seems that how much you eat will not affect people.
So, do you really understand antioxidants, and are antioxidants harmful to eating more?
<h1 class="pgc-h-arrow-right" data-track="3" > oxidants: by-products of oxygen</h1>
All antioxidant health product advertisements will first emphasize the harm of oxygen free radicals, so what exactly are oxygen free radicals?
There is a organelle called mitochondria in human cells, which can use nutrients obtained from food to chemically react with oxygen molecules obtained from breathing, and convert them into energy that can be used by the human body, and those that cannot be combined and converted into energy become oxygen free radicals.
Oxygen radicals are very active, if there are too many oxygen radicals in the body, it will destroy the structure and function of the cell membrane, destroy the mitochondria, cut off the energy of the cells, and even make the cells autolysociate, thus causing a variety of diseases, such as heart disease, Alzheimer's disease, Parkinson's disease, tumors, etc. In addition, sunlight radiation, air pollution, smoking, pesticides, etc. in the external environment will make the human body produce more oxygen free radicals, which is one of the root causes of human aging and disease.
Under normal circumstances, cells will not be easily damaged by oxygen radicals, because the human body has a large number of natural enemies of oxygen radicals - antioxidants, such as vitamin E, vitamin C and some enzymes, etc., these antioxidants can react with oxygen radicals oxidation - reduction reaction, the two "end together" to protect the body.
When the human body suffers trauma, poisoning or excessive bleeding, the oxygen free radicals increase sharply, and it is impossible to transport enough antioxidants through the blood to fight it, which will cause very serious damage to human cells and non-cellular structures, and even lead to human death.
<h1 class="pgc-h-arrow-right" data-track="3" > antioxidant: indispensable</h1>
Antioxidants are a collective term for a class of substances that can trap and neutralize oxygen free radicals and remove damage to the human body, the most familiar of which are vitamins C and E, and most antioxidant health products are derived from these two substances.
Vitamin C, also known as ascorbic acid, was discovered because hundreds of years ago, European ocean-going sailors often had bleeding gums, ecchymosis and bleeding from the skin, and even died painfully, known as scurvy, and later a shipwright doctor learned that the long-term inability to eat fresh fruits and vegetables was the cause. After research, vitamin C has promoted collagen formation, made the skin firm, bones and teeth strong, promoted wound healing, enhanced immunity, promoted the absorption of minerals such as calcium, phosphorus, iron, and reduced the content of cholesterol in the blood to reduce arteriosclerosis and other effects. Of course, as an antioxidant, it can also effectively scavenge oxygen free radicals in the body, preventing the conversion of nitrite in pickled foods to produce carcinogenic nitrite amines.
Vitamin E is found by medical scientists in the process of studying reproduction in the 1920s, which can promote the secretion of sex hormones, increase the vitality and quantity of sperm in men, improve female fertility, and is often used clinically to treat threatened miscarriage, recurrent miscarriage, menopausal syndrome, male infertility, etc., which also helps to improve immunity and reduce the risk of myocardial infarction and cerebral infarction, burns, frostbite, beauty and so on.
<h1 class="pgc-h-arrow-right" data-track="3" > antioxidants eat more and hurt the body</h1>
Although antioxidants have many important physiological effects on the body, it does not mean that the more content in the body, the more powerful the function, the better the effect, in the case of sufficient body volume, too many antioxidants can cause harm to the body.
Research by the journal American Medical Association, an authoritative medical journal, shows that long-term additional vitamin E not only has no benefit, but increases the risk of prostate cancer by 17%. Studies in the New England Journal of Medicine have also shown that vitamin E not only does not reduce the incidence of lung cancer in smokers, but also greatly increases the incidence of lung cancer.
The spearhead of these studies is directed at overdose of vitamin E, because it is fat-soluble, easy to accumulate in the body, and once overdose is not easy to excrete. Relatively speaking, vitamin C is water-soluble, can be excreted with urine and sweat, not easy to accumulate, and has always been considered to be highly safe, but if it is taken for a long time or in large quantities, the situation is also not optimistic.
Long-term high-dose taking vitamin C can cause high-iron erythrocyte anemia and reduce the absorption of vitamin B12 by the intestine; for example, more than 3 grams per day, it can cause hyperlitation, diarrhea, abdominal pain, and when severe, it can lead to gastrointestinal bleeding, aggravate gastritis and gastrointestinal duodenal ulcer disease; it will make the disease resistance of white blood cells significantly decrease, delay the course of certain infectious diseases and rheumatism; cause hyperuricemia, accelerate the formation of kidney and bladder stones. In addition, vitamin C can not be combined with a variety of trace elements and drugs, otherwise it will reduce the efficacy or increase side effects. Even the U.S. Food and Drug Administration has pointed out that there is no scientific evidence or important research that can prove that vitamin C has the effect of preventing and treating colds.
Other antioxidants suffer from the same embarrassment — studies have found that women who take vitamin supplements for long periods of time have a 2.4 to 6 percent higher mortality rate than those who don't. Some authoritative medical journals such as The Lancet have published many studies, showing that excessive antioxidant supplementation not only has no effect on common cardiovascular diseases and cancers, but also has various unintended consequences, increasing the risk of disease and mortality.
<h1 class="pgc-h-arrow-right" data-track="3" > natural antioxidants are in food</h1>
From this point of view, the harm of antioxidants is not less than that of oxygen free radicals, but there is no need to be afraid of it, because its damage to the human body is based on the premise of "excess". So when exactly can it be replenished, and when is it excessive?
In theory, most antioxidants come from a variety of natural foods, and people can get enough vitamin C and vitamin E from food, as well as carotene, lycopene, anthocyanins, astaxanthin, lutein, selenium and so on. Among them, sweet potatoes, corn, asparagus, cauliflower, eggplant, tomatoes, beets, cabbage, spinach, potatoes, enoki mushrooms, Chinese cabbage, mangosteen, hawthorn, green tea, grapes, seaweed, blueberries, grapefruit, oats and other common foods are rich in antioxidants, just daily consumption, can meet the needs of the human body, more importantly, how to eat these vegetables and fruits are difficult to make antioxidants excessive.
When processing food, it is best to reduce heating, blanch the water cold mix, stir fry quickly or eat raw, you can avoid the loss of antioxidants in the cooking process. Dishes are best eaten as soon as they are cooked to reduce the residual temperature of the dish and to further heat and reheat to fight the destruction of oxidative ingredients.
Additional supplements are required only when adequate amounts of antioxidants are not available in the daily diet, or when the body's needs are increased, or the absorption utilization rate is reduced, such as people who do not eat vegetables and fruits for a long time, pregnant and lactating women, children in the growth and development period, patients in the recovery period of disease, and the elderly with reduced gastrointestinal function. Even so, you should follow the doctor's advice to buy antioxidants as drugs, rather than eating green health products on your own, otherwise it may lead to the problem of overdose.
The relationship between oxygen radicals and antioxidants is intricate, the current discovery is only the tip of the iceberg, there are many complex life activities involved, unauthorized disruption of the body's balance is not wise, want to supplement the antioxidants, lazy to obtain health is more unreliable. Only by following the correct concept and practicing a healthy lifestyle in a down-to-earth manner can we truly stay away from diseases. #抗氧化 #