What vitamins and minerals should I take to prevent upper respiratory infections?!?

The short answer is, “None that we know of.” But the title caught your attention, didn’t it?  Unfortunately, these are the kinds of headlines I’ve been seeing a lot of lately, especially related to COVID-19.  It truly distresses me to see people who are looking for help for themselves or a loved one, and to watch some “snake-oil salesperson” make money off innocent victims they see as, “marks.”  As some of you know, I’m a nutritionist—not the kind of nutritionist who took an online course during the pandemic and proudly display my downloaded certificate—but one who spent 6 years getting my doctorate in nutritional biochemistry and the intervening 40 years researching, practicing, reviewing, and writing about other people’s research on nutrition. Some of you know I even started blogging about nutrition a few years ago. And then I got a little quiet. Well, I’m back! Writing about nutrition. So, since it’s been a while, I thought I would let you know what I’ve been up to since I last posted, followed by an overview of my philosophy. Some of it is stuff a number of you may remember me commenting on before and some of it is new.  Finally, I’ll add a preview about the subject of my next blog, which is something I’d like to do for each future writing!

Finding good nutrition advice today is tough!  Sometimes even I get tripped up by stuff I see on the internet, and I end up having  to do a deep dive into volumes of studies on the controversies surrounding the research on a particular kind of fat or protein or carbohydrate or vitamin…Invariably, the controversies are about how the studies were conducted—or whether any studies were conducted at all (believe it or not, some self-proclaimed experts just like to say things, based on no evidence!). Such was the case when I was asked by a medical journal—in the middle of the pandemic—to serve as a peer reviewer for a manuscript that purported to review all the studies ever done on whether vitamins and minerals can prevent upper respiratory infections (like COVID-19, but not COVID-19)!

I’ll describe my trip down the vitamin and mineral rabbit hole in another blog, but suffice it to say those ads you hear and articles you read touting the “miracle” of vitamin C or D or zinc or silver or worming medication that will cure/prevent COVID-19 call to mind that scene from the film, Oklahoma, of Ali Hakim, the snake oil salesman hawking his “magic elixirs” out of the back of a wagon. Or Professor Marvel in the Wizard of Oz.

I also spent the past year or so, with my husband’s invaluable help, revising the nutrition “encyclopedia” on my website (the one I hope you’re on now or will soon go to). Because if you can read a straightforward explanation of how nutrition works, it’s harder to be fooled by the constant barrage of nutrition news and advice that comes at us from every news outlet; every well-meaning relative, trainer, or friend; and every not-so-well-meaning “expert” who is trying to make a financial killing on your health!

From now until you all tell me to stop or to switch to writing about another topic or to post pictures of our cute dogs instead, I will, once a week or so, briefly tackle some nutrition topic that’s recently hit the news. If you want to learn more about the topic or you have another question, feel free to email me and we can work through the issues—together.

So, why is it so difficult to find good nutrition research and advice?

If you’ve read my blogs or my website before, you know the answers, but since it’s been a while since I posted anything, or you might be new to my blogs, here is a short summary.

First, good, trustworthy nutrition research is really difficult to do in humans. Why?

• It’s really hard to measure the amounts of some nutrients in our bodies and even harder to know if we’re measuring in the right place. So people look for quick and easy answers.  Think of the drunk searching for his lost car keys at night under the streetlight—not because that’s where he thinks he lost them but because, “that’s where the light is!” This challenge has lots of implications. For example, if I want to learn whether the amount of dairy food you’re eating (because dairy foods are high in calcium) is helping to keep you from developing osteoporosis (put simply, a disease in which the bones start to lose their main constituent, calcium, and become prone to fracture), I can measure the calcium floating around in your blood, but that one measurement doesn’t tell me anything about how much calcium is in your bones, not to mention how much was there 5 years ago, and why you’re losing it, if you are.  See the difficulty?
• Besides the challenge of not being able to measure the right nutrients in the right parts of our bodies at the right times and not knowing whether what we’re measuring is important, it’s exceedingly difficult to figure out what people actually ate: It turns out most of us are not terribly accurate at recalling what we ate this morning or yesterday, not to mention last week, last year, or decades ago when we were teenagers! And even if we’re pretty good diet historians, one serving of a hamburger or American cheese or Post Toastees can actually differ from another, AND each of us might metabolize them a little differently, and those differences add up surprisingly quickly. This is why controlled studies are important and take a long time.  Sorry about that!
• And people make terrible guinea pigs because we tend to crave what we can’t have or are told to stay away from. For example, if you agree to be in an experiment of mine and I tell you that you can’t eat okra or pickled pigs’ feet for a month, guess what you’re going to be googling recipes for? And speaking of guinea pigs, research that is done on lab animals often has no application to humans. EXAM TIP!!!  The next time you hear someone tout a “miracle treatment,” check  whether any experimental trials were performed in humans! 

In sum, because human nutrition research is exceedingly challenging, the research findings you hear and read about online or in mainstream media are often suspect, based on one or two poorly done studies of a small number of people and exaggerated in importance by the tendency to overinterpret the results and jump to unwarranted conclusions. The only credible nutrition advice is advice that is based on a careful synthesis of the findings of a series of well-designed, studies.

Please don’t misunderstand me: I am not saying all nutrition advice or advertisements are bogus.  I’m simply saying you need to critically analyze what you hear and read, and look for corroborating evidence because…

The second reason good nutrition advice is hard to find is that many (not all but a lot) of the people who give you nutrition advice—the specific you or the general you—are trying to sell a product. It could be a book, a dietary supplement, an endorsement, their latest research proposal, hours of their consulting or clinic time, even space on their website. Sadly, some of these people are extremely intelligent, experienced research scientists and health care providers who have just succumbed to the lure of the millions of dollars to be made selling miracles. Or if they’re not trying to sell their product, they’re your well-meaning aunt or neighbor, telling you, “Well, my grandmother drank apple cider vinegar every day and she lived to be 96. You have to try it.” Scientific research looks for proof of cause and effect, and sadly, your grandmother’s longevity doesn’t count. Apple cider vinegar doesn’t do anything except make money for the people who manufacture and advertise it. And what about apple cider vinegar gummies!!! Don’t even go there!  So, the next time you hear a nutrition recommendation, ask yourself: is the person offering this advice benefiting in any way financially from you buying it?

If you’re beginning to get the idea that solid, high quality nutrition research is rare, it’s easier to see why the nutrition advice that’s really backed by solid evidence— eat more whole grains and vegetables, get your vitamins and minerals from food, exercise—sounds much less miraculous and more like just plain hard work than the advice to, “Just take this pill.” I will quote as many other sources of the truly evidence-backed advice as I can find—so you know who else to trust and so you don’t think I’m just dumping on glowing stars like Dr. Oz. Or the Wizard of Oz.

I’m not trying to sell you anything! The world of nutrition research is just my world, and I’m back to be your tour guide. So, fasten your seat belts and mask up—at least ‘til most of us are vaccinated! In my next blog I’ll delve a little further into the COVID-19 and Vitamin D story.  Until then, happy eating everybody!!