See which vitamins our registered dietitian recommends as the best for…. Gummy vitamins are increasingly popular. This article tells you whether they are good or bad for your health. Health Conditions Discover Plan Connect. You are what you expect. Some positive research.
Food first for nutrition. The industry point of view. Quality matters. Read this next. The Surprising Truth. Magnesium for Migraines When taken in safe doses, magnesium can effectively prevent migraines for many people. The 10 Best Multivitamins for Women Over The first reviewed three large trials of multivitamins and 24 trials of single or combined vitamins involving over , people.
The conclusion: no convincing evidence that the supplements prevent or delay cancer, heart disease or death. The second study, a randomized trial following 5, men aged 65 or older for 12 years, found no difference in the mental functioning or verbal memory of those who took a multivitamin versus those who took a placebo. The third compared a high-dose, component multivitamin with placebo in 1, men and women who had survived a previous heart attack.
After 4. Of course, all vitamins, by definition, are essential for health in small amounts. And while doctors do sometimes prescribe particular vitamins to treat specific medical conditions, most of us get all we need from food.
Just 43 percent of those with only a high school education said they took a vitamin, compared with 51 percent of those with some college, 55 percent of college graduates and 65 percent of those with postgraduate degrees. No reliable national polls on the subject have come out since. But a May report by Nielsen examined sales data from 91, grocery, drug, convenience and value stores, analyzing approximately , individual SKU product codes in 53 categories — in other words, pretty much everything sold in retail outlets.
Internet sales in the category grew at an astonishing Because of the Dietary Supplement Health and Education Act of , manufacturers of vitamins, herbs and other supplements are not required to prove to the FDA that a product is either safe or effective before selling it.
This is respiration, a mechanism that fuels all complex life. In addition to food and oxygen, a continuous flow of negatively charged particles called electrons is also required. Like a subcellular stream downhill powering a series of watermills, this flow is maintained across four proteins, each embedded in the internal membrane of the mitochondria, powering the production of the end product: energy.
This reaction fuels everything we do, but it is an imperfect process. There is some leakage of electrons from three of the cellular watermills, each able to react with oxygen molecules nearby. The result is a free radical, a radically reactive molecule with a free electron. In order to regain stability, free radicals wreak havoc on the structures around them, ripping electrons from vital molecules such as DNA and proteins in order to balance its own charge.
Although inconceivably small in scale, the production of free radicals, Harman and many others posited, would gradually take its toll on our entire bodies, causing mutations that can lead to ageing and age-related diseases such as cancer.
In short, oxygen is the breath of life, but it also holds the potential to make us old, decrepit, and then dead. Clinical trials are the only ways to reveal the effects of a drug - and investigations into antioxidants have produced some shocking results Credit: Alamy. Shortly after free radicals were linked to ageing and disease, they were seen as enemies that should be purged from our bodies.
It is hoped that [this theory] will lead to fruitful experiments directed toward increasing the healthy human lifespan. He was talking about antioxidants, molecules that accept electrons from free radicals thereby diffusing the threat. And the experiments he hoped for were sown, nurtured, and replicated over the next few decades. But they bore little fruit. In the s and into the 80s, for example, many mice — our go-to laboratory animal — were prescribed a variety of supplementary antioxidants in their diet or via an injection straight into the bloodstream.
Some were even genetically modified so that the genes coding for certain antioxidants were more active than non-modified lab mice. Far from protecting us from disease, one study found that vitamin supplements increased the incidence of lung cancer among smokers Credit: Alamy. What about humans? But what they can do is set up long-term clinical trials. The premise is pretty simple. First, find a group of people similar in age, location, and lifestyle. Second, split them into two subgroups.
Third, and crucially to avoid unintentional bias, no one knows who was given which until after the trial; not even those administering the treatment. Known as a double-blind control trial, this is the gold standard of pharmaceutical research. Since the s, there have been many trials like this trying to figure out what antioxidant supplementation does for our health and survival. The results are far from heartening. In , for example, one trial followed the lives of 29, Finish people in their 50s.
All smoked, but only some were given beta-carotene supplements. A similar result was found in postmenopausal women in the U. It gets worse. One study of more than 1, heavy smokers published in had to be terminated nearly two years early. Compared to placebo, 20 more people were dying every year when taking these two supplements.
Over the four years of the trial, that equates to 80 more deaths.
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