A few days ago I gathered seven nearly full bottles of supplements, including apple cider vinegar capsules and a daily multivitamin, and put them in my trash can. I had just read some articles explaining that studies have linked vitamin supplementation with higher mortality rates.
Five minutes later, I worried that perhaps I was being too extreme, that maybe years down the road researchers would do some other studies that would show different results, or that in a few months I would realize that I needed one of these supplements for some reason and then would curse myself for wasting tens of dollars by throwing them away before their expiration dates.
I took them out of the trash and put them back in a drawer. I wouldn’t continue taking them, I told myself, but I would leave them there, just in case.
My back-and-forth is emblematic of the general public’s relationship with health advice. In short, many of us just don’t know what the heck to believe. It’s no wonder. We have 
But science is all we’ve got, imperfect as our conclusions about it may be. The best we can do is pay attention to what the vast majority of experts in any given field are saying. That means based on quality research, which relies on science. In that spirit, let’s take a look at four myths that science suggests we should retire.
Myth: Megadosing on vitamin C will help your cold.
Something most of us have grown up hearing and believing is that if you’re coming down with a cold, you should coat your insides with vitamin C. Whether you’re downing orange juice, taking chewable vitamin C, dumping vitamin C packets in your water, or dropping an Airborne tablet in an after-work drink and hoping for the best, so many of us take for granted that this is doing something. But guess what. It probably isn’t!
Despite people’s enduring belief that vitamin C supplementation (often in doses far exceeding the recommended dietary allowance) is the appropriate course of action when sneezing sets in, study after study suggest that it provides no benefits.
“What we know is that people who eat a lot of naturally occurring vitamin C in foods, do have a lower risk for the common cold,” Shelley McGuire, national spokesperson for the American Society for Nutrition and an associate professor of nutrition at Washington State University, tells Live Science.
“However when scientists isolate just vitamin C and do studies, they’re very rarely able to show vitamin C reduces the incidence (how often someone catches a cold) or the severity of a cold.”
Myth: Eating fat will make you fat.
When was the last time you felt satisfied after eating fat-free cookies with skim milk? Unless you have especially strong mental powers—which, to be fair, some people really do—your brain probably registered the experience as relatively low-reward.
Why? Because fat is satiating. That’s one of the reasons why, contrary to popular belief, eating items with a lot of fat in them will not, as a rule, make you gain weight. They can actually make you eat less, since you’re more satisfied.
“Fat can make you fat, but so can carbohydrates and (to a much lesser degree) protein; it just matters that you over-consume the source of calories,” Dr. Spencer Nadolsky tells Lifehacker.
“Granted some fats are seen as ‘b
etter’ than others (such as coconut oil and fish oil relative to trans fats) which accounts for some variability in weight gain, but weight gain will occur when ‘excess’ is consumed (whatever that may be to your body).”
Then why do we continue to see so many fat-free things in grocery aisles? We can thank a diet craze that took hold in the 1990s for that. Although it may be true that many fat-free items are often lower in calories, since fat is very calorie dense, it is not true that these options are always healthier. In order to make up for the loss in flavor that comes with removing fat, food manufacturers often add more salt and sugar.
“What’s really important though is how satisfying a diet is, because we have very complex mechanisms that control our total intake of calories, and it’s become pretty apparent that if we have a high-carbohydrate diet, particularly high refined carbohydrate, it makes it much more difficult to control our total caloric intake,” nutritionist Walter Willett points out.
“That’s probably because when we eat refined carbohydrates, we get these swings in blood glucose and insulin that lead to hunger between meals; whereas if we have a diet that’s somewhat higher in fat, we tend to be more satisfied over the long run.”
Myth: Vitamin supplementation is healthy.
What if something you took for granted as a sound piece of medical advice was actually just a result of corrupted information and false marketing? This would appear to be the unsettling truth about not only vitamin C supplementation but about vitamin supplementation in general. How has this false belief become common knowledge?
According to Paul Offit, a pediatrician specializing in infectious diseases and an expert on vaccines, immunology, and virology, it can all be traced back to one man… “A man who was so spectacularly right that he won two Nobel Prizes and so spectacularly wrong that he was arguably the world’s greatest quack.”
In his book Do You Believe in Magic? The Sense and Nonsense of Alternative Medicine, Offit traces the fascinating, tragic rise and fall of Linus Pauling, who, despite being brilliant and well respected for his early work, is also responsible for widespread misbeliefs about vitamin supplementation, especially vitamin C.
“Although studies had failed to support him, Pauling believed that vitamins and supplements had one property that made them cure-alls, a property that continues to be hawked on everything from ketchup to pomegranate juice and that rivals words like natural and organic for sales impact: antioxidant,” writes Offit.
The problem? In application, vitamin supplementation does not work—and, in fact, it appears to be harmful. Studies showed this repeatedly, but Pauling rejected their findings.
Amid mounting evidence against Pauling’s theories (that he nevertheless continued to support through the end of his career), the scientific community began to reject his credibility. The media and the public, however, did not. They still knew him as the well-respected scientist who had won two Nobel Prizes.
Stephen Barrett, MD, writing for Quackwatch, sums upU.S. National Library of Medicine
Pauling’s legacy like this:
“Although Pauling’s megavitamin claims lacked the evidence needed for acceptance by the scientific community, they have been accepted by large numbers of people who lack the scientific expertise to evaluate them. Thanks largely to Pauling’s prestige, annual vitamin C sales in the United States have been in the hundreds of millions of dollars for many years.”
Myth: Gluten-free is the way to be.
How many times have you heard about the evils of gluten (the proteins found in wheat)? Lots, yeah?
Let’s see if we can do this from memory: Gluten intolerance is at the root of a number of physical and mental problems for people in countries with many processed foods, because wheat is hiding in everything that we eat, and now we’ve screwed ourselves. The story goes something like that, right?
It makes sense. We are frequently tired! We have skin problems! We eat lots of wheat! Wouldn’t it logically follow that the best thing we could do would be to eat foods without gluten and give our systems a break?
Dr. Carly Stewart doesn’t think so. “Gluten-free foods are only healthier for you if you are allergic to gluten. If you aren’t, eating a gluten-free diet restricts the amount of fiber, vitamins, and minerals you are able to consume,” she tells Lifehacker.
“A variety of foods that are high in whole grains (such as foods containing wheat, rye, or barley) also contain gluten, and these foods are an essential part of a healthy diet. Most people have no trouble digesting gluten.”
In other words: Making it harder on yourself to eat a varied, healthy diet isn’t recommended. Why put yourself through that if you don’t have to?