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Share on Pinterest Design by Diego Sabogal. What are antioxidants? Antioxidant defense systems. View All. Clean eating: What does the research say?
Carbohydrates: Are they really essential? How bad are carbs, really? Antioxidants in food vs. Can antioxidants harm health? The bottom line.
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Two researchers tell the story of how the pandemic completely altered their research topic and how they dealt with it. Some antioxidants have a positive effect on your health, but not in the way you may have imagined. Photo: Shutterstock. This makes sense: cancer cells are metabolically very active, so they produce huge amounts of free radicals as a side effect of their metabolism. This means that especially cancer cells benefit from antioxidants that neutralize free radicals.
Other studies show that antioxidants can undo the beneficial effects of exercise R. One problem is that antioxidants, when taken orally, cannot enter the regions in the cells where they are most needed, and this in high enough concentrations. But even then, studies in which animals are genetically modified to produce much more antioxidant enzymes like catalase , do not live longer. Such antioxidant enzymes work much better than antioxidants small-molecules taken by mouth, but still they do not seem to have significant effects on lifespan.
Even more confusingly, mounting evidence shows that the substances antioxidants are supposed to neutralize, free radicals, can even have life extension effects. How is this possible? These exercise-induced free radicals activate all kinds of repair and defense mechanisms in our cells, so that the cells can better protect themselves against the next time you exercise. In the meantime, these revved-up defense and repair mechanisms also protect you against aging and aging-related diseases.
Besides exercise, we know that foods like vegetables, fruits and green tea are healthy. The classic, main explanation for this is that these foods contain antioxidants.
His work on molecular bonding was groundbreaking, and Francis Crick credited him as the father of molecular biology. In the s, he was a leading proponent of the vitamin healing movement. His work in this area has largely been debunked, which begs the question of how such a brilliant scientist could be led astray.
The treatment appeared to restore his health and sparked his curiosity about the potential role of vitamins in other diseases. He was especially enamored with vitamin C, taking up to 3 grams per day. Geniuses are often blinded by the seductiveness of their own ideas. Pauling was convinced that if oxidation is destructive, then antioxidants must be beneficial.
Such a simple, elegant idea must be true, right? The modern-day evidence-based medicine movement warns against such reasoning from physiological mechanisms. A treatment must go through randomized clinical trials or other rigorous testing before it is considered validated.
It must work in the real world, under controlled conditions. He never wavered in his conviction that vitamins, especially lysine and vitamin C, could be used to prevent colds, reverse heart disease, and prolong the life of terminal cancer patients.
One clear win for vitamin C is its prevention of scurvy — a horrific disease that inhibits collagen production. Collagen is the protein that makes up our connective tissues, and our body literally falls apart without it. In the mids, Sir James Lind discovered citrus fruits could eradicate scurvy.
The reason why remained unclear until the s, when it was discovered that vitamin C was the mechanism behind the cure. Most animals can synthesize the vitamin, but humans, other higher primates, guinea pigs, and fruit bats cannot. To the extent we need it, it must come from our diet. Although, unlike the animals who can synthesize their own, we can resynthesize vitamin C from its oxidized form.
This greatly reduces our need compared to other species who cannot recycle it. Barry Sears describes three main types of antioxidants:. Research suggests high-dose antioxidant supplements are ineffective or outright dangerous.
It is speculated that a diverse intake of antioxidants might be more healthy. Sears recommends an intake of polyphenols of to 1, mg per day. Food manufacturers frequently tout the antioxidant levels in their junk food products. Even if you strongly believe in the value of antioxidants, you should not make food choices on that basis alone. Your antioxidant needs are proportional to the amount of oxidative stress you are exposed to.
In certain extreme cases, antioxidant supplementation can be helpful. Many antioxidant supplementation success stories are found in malnourished populations subsisting on grain-based diets. Such populations need to supplement with antioxidants to counter the effects of carbohydrate overconsumption and malnutrition. For example, vitamin A deficiency weakens the immune system and is the leading cause of preventable blindness.
About half of the blinded children die within a year. Antioxidants have many benefits. However, when isolated from food products and packed into high-dose supplements, they rarely show any benefit in the human body and are sometimes harmful. Here is what some of the research has to say:.
The failure of vitamin C supplementation to reduce the incidence of colds in the general population indicates that routine vitamin C supplementation is not justified, yet vitamin C may be useful for people exposed to brief periods of severe physical exercise. In most cases, no effect of intervention was observed on mortality, except in specific subgroup analyses e.
However, there have been few of these studies published to date, and even fewer of high methodological quality. Other commonly assessed outcomes included ICU and hospital length of stay, duration of vasopressor support and mechanical ventilation, and acute kidney injury. Some of the meta-analyses showed decreases in several of these secondary outcomes, while others showed no effect, depending on the selection criteria used for study inclusion.
We found no evidence to support antioxidant supplements for primary or secondary prevention. Beta-carotene and vitamin E seem to increase mortality, and so may higher doses of vitamin A. Some studies have shown potential harms associated with vitamin supplementation.
Numerous studies have shown increased risk of mortality among people who take multivitamins. These studies are observational and cannot prove cause and effect.
Their outcomes may be due to the fact that sicker people are more likely to take vitamins. There is very little regulation or quality control in the supplement industry. Often, what is inside the pill bears little resemblance to the ingredients listed on the package. In most cases, antioxidant supplementation represents a failed attempt to outsmart Mother Nature. Many would like to believe vitamins are magic pills that allow a person to thrive on a diet of Pop-Tarts and soda.
Replacing the nutrients lost during industrial food processing is a band-aid solution to the myriad problems caused by those same highly refined foods. It really would be great if everybody just needed to eat the "right" way and the result would be a healthy organism without any deficiencies. I am regularly blood testing me and many of my patients and I often find deficiencies in minerals, trace minerals or vitamins.
I know that blood levels are not the whole of the story, but thats what you can measure. By taking supplements you can see changes in blood levels, and often the condition improves. So what is so wrong about it? In addition to this thoughts here is an article on Vitamin C released in Medium HQ themselves cited another article from Medium a few days ago, so I think it is well accepted as a resource Daniel, it sounds like you have a smart approach to supplementation.
I briefly mentioned to Pat B below that getting blood work done is a wise thing to do before you start randomly taking supplements.
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