If you believed the internet, you'd think there's huge debate over whether eggs, coffee or salt are good or bad for you. In reality, there's significant agreement on diet and health issues among experts, but the general public is conflicted. So why are we so confused when experts agree? Let's clear the air.
If you asked a dozen people about foods that are "good" or "bad" for you, you'd get a dozen different answers. You'd find people who vehemently argue that eggs are both good or bad for you, that sodium does and doesn't contribute to hypertension, or that carbs do or don't make you sick. In general, you'll find a lot of laypeople with opinions that may or may not be based in real science. Researchers however, generally have some solid and well-founded opinions on these issues, and are quick to note where their own shortcomings are.
So where's the disconnect? In this post, we'll look at where the breakdown happens, who's to blame, and what you can do about it all. We sat down with a number of our own experts to get their input. It's going to be a bumpy ride, so let's get started.
The "Health And Diet" Industry Carries Much Of The Blame
Health and diet products are big business. From books and meal plans to prepackaged foods and DVDs, we eat the stuff up (pun intended). It's natural to be attracted to a path that promises big results for little effort, but there's more to it. People who would otherwise consider themselves rational are often duped by marketing and half-truth statements made in the name of science.
This is where the diet industry flourishes. By taking advantage of the public's desire for practical health information, so-called "experts" sell us everything from juicers to supplements, convincing us the whole time we'll live forever thanks to their advice. It shouldn't work, but it does. Beth Skwarecki, a science writer and educator, explains why:
We respond strongly to warnings about danger, and promises of really awesome stuff (like health, or weight loss) — but only if those warnings or promises are actionable. And with food, that really applies: We can act on a warning to avoid gluten or eat superfoods (or whatever) at our next meal or our next trip to the grocery store. It makes us feel good to have control over ourselves. I'm not a psychologist and this is just my personal opinion, but I'm sure there is research that backs this up. Why this causes confusion: Truth and falsehoods are both presented this way. "Vitamins are magical substances that will make you more healthy if you are deficient!" Well, yeah. That's actually true. "Vitamins are magical substances that will make you more healthy!" Sounds similar, but it's not the same, and it's not true in most cases. Then you can substitute various other chemicals or superfoods for the word "vitamins" in that sentence. True claims and misleading ones sound very similar.
People selling diets or exercise programs will latch on to true things that help them sell their product; they will also latch onto false ones. Just look at Dr. Oz: plenty of what he's pushing is true, but lots of it isn't, or is misleading. Which is which? I don't know that he cares. He just needs a steady stream of things to endorse.
We don't meant to particularly single out Dr. Oz here. There are a number of physicians and other medical professionals who are highly educated, but have made the decision to "sell health". They may believe they're doing good, or just want to make a living. In all of those cases, the message is similar: "Living healthy doesn't have to be hard, just do this thing/eat this food/buy my book."
Selling health is only half of the job. The other half is undermining public trust in science-based medicine and traditional authorities (although they carry blame too — we'll get to that in a moment) so they can swoop in to the rescue. Andy Bellatti, registered dietitian and frequent Lifehacker contributor, explains:
The food industry thrives on confusion, and it loves to propagate the notion that "Gee whiz, one day you're told coffee is good for you, the next day you're told it's unhealthy!" By making nutrition advice seem "confusing," they attempt to gain the public's trust. It also doesn't help that, increasingly, food companies are setting up "institutes" (i.e.: Coca-Cola's Beverage Institute for Health and Wellness, General Mills' Bell Institute) that are essentially PR efforts that oh-so-coincidentally frame these companies' products as healthful (or, in the case of soda, in no way problematic from a health standpoint). To make matters more confusing, these institutes have doctors, cardiologists, and dietitians on their payroll — as well as key media contacts — resulting in a health professional talking to media about, say, how soda is "unfairly vilified." Most times, the general public isn't aware that this isn't an objective health professional choosing to say that.
When we debunked stubborn exercise myths, we ran headlong into one of these groups. The "Gatorade Sports Science Institute" has papers explaining why Gatorade is better than water for exercise — papers we saw copied word-for-word on other sites. In reality, depending on the exercise you do there's either no difference between water or sports drinks, and for most people there's clear evidence that water is the better option.
All of these tactics may seem underhanded, but they're just part of the marketing game. By playing on the public's confusion and presenting their own products as quick fixes they convince us to buy their books, follow their diet plans, and perhaps most dangerously, ignore legitimate advice and real research.
It's not just companies that do this though. Individuals with a message to sell also do it. Skwarecki's article, Why It's So Easy to Believe Our Food is Toxic, is an exceptional case study in this. She explains how "experts" take good premises — like the need to take your health in your own hands and be critical of the things you eat and buy — and go off the rails when the sales pitch gets involved. She calls out nutrition gurus and health "experts" you've probably seen reposted on Facebook, like Vani Hari (aka The Food Babe,) and Joseph Mercola, among others, who thrive on obfuscating nutrition so much that the only clear thing they do suggest is that you should buy their books, sponsored foods and DVDs.
Food industry marketing firms and "diet guru" salesmen both use the same tactics, and both groups make money from your fear and lack of knowledge about health. You should treat both with the same sceptical eye, even if one's message is more attractive than the other.
The Media And The Scientific Community Communicate Poorly
Surely science-based medicine must offer useful data that we can all use, right? Not quite. When I asked Skwarecki about it, she explained it this way:
The other reason there is confusion? Because there really ARE old beliefs that were held as true that are being corrected. Saturated fat is a subject with genuine controversy. Experts have not come to a consensus, but decades of public-health messages are in the process of being potentially overturned. When you hold to something as a foundation (Of course fat is bad for you! Of course stretching prevents injury!) and that belief gets challenged, you're tempted to give up on everything. It's a very reasonable thing to do: My facts were wrong, I need to reevaluate all my facts.
The truth is, while there's consensus on many things, there's a huge lack of it on others. Epidemiology, or the study of the patterns and causes of disease, is extremely difficult to do. Says nutrition researcher Kamal Patel:
Nutritional epidemiology is a really, really tough thing to study. Harder than most other areas of health. Much harder than it sounds. Some people think "Oh nutrition! I know about food and nutrition! That's much easier than some analysing some obscure medication that I can't even pronounce." Wrong. Medication effects can be complex, but nutritional epidemiology makes that look like child's play. ... It's easy to see how the public can get mixed messages. Research results are notoriously unpredictable, since only some of the total number of studies get published. Studies have a higher chance of getting published if they show positive results, and food and supplement manufacturers can keep funding trials until one gets published. Nutrients interact with each other, so the effects of any one nutrient are hard to predict, let alone the effect of any one food in the midst of a diet comprised of dozens or hundreds of foods. So while I don't agree with everything Michael Pollen says, his message is generally on point: "nutritionism" is bound to fail. If you obsess about your diet and individual nutrients, you not only lose the benefit of of the occasional cronut or thanksgiving dinner, but you lose the forest for the trees. Natural foods are what's healthy, nutrients and the controversies they cause are what keeps research dollars flowing and flip-flops popping up every couple weeks. It's important to get nutrients, but it's wise to get them mostly through food, and only after that supplement what you need in a very targeted manner.
In short, the science here is complex, difficult, and slow-moving. Patel explained that while there is consensus on some things, everyone's body is different. For every factor where there is agreement, there's another factor that influences everything:
There is a rough agreement that a balanced diet is probably a good idea. While there are some regular people who experiment with meat-only diets, macrobiotic diets, etc, most researchers are old dudes who eat normal diets and believe that vegies and fruits and whole grains are good, and red meat is bad, and some other things are in between. I'm just one person who has had the opportunity to make a career out of reading articles and grading their study quality — but I can honestly say that I don't know what is correct for sure. Gluten and wheat is bad for some people, low carb could help certain diabetics but so could a very nutritious diet, and low carb can also cause side effects in some people. Some people live long lives with "healthy" diets, some live long lives eating milk chocolate and fried chicken every day. For any specific nutrient, I can summarise the evidence. And for any type of diet, I can find the totality of observational evidence for it. But there haven't been many (any?) long term randomised trials of low carb, high carb, etc etc. It would be too expensive, deemed unethical, and just not logistically feasible for compliance — the primary researcher for long term observational trials (where they just follow people and collect data, not make them eat certain diets) often die in the middle of the trial, so it's quite an effort to keep a long randomised trial going that costs millions. Especially when food trials are funded at levels so much lower than pharmaceutical trials.
This is where the media comes in. Research that you hear about may be just one study designed to tackle a specific angle to a much larger problem. This is where the media (yes, ourselves at Lifehacker included) are at fault. Preliminary results published and popularised as cure-alls, rat cures touted as future human cures, it makes the public believe every miracle is a few trials away, and when it's not, people are frustrated and confused. This kind of poor communication and science reporting is a topic we've covered before in detail, and it plays a huge role in making the public's perception of science and medicine worse. As a result, it sends people running into the arms of diet hucksters and snake oil salesmen, eager to capitalise on that lack of trust.
We Are Predictable And Easily Influenced
We're part of the problem too. Our buying habits are predictable and easy to capitalise on. Our psychology is even predictable, and well-studied by marketers. The power of the word "natural" to drive sales even though we all know it's meaningless is a good example, as it the fear around the word "processed" without context.
The scare over the "yoga mat chemical" (aka azodicarbonamide) is a good example too - we're poorly educated when it comes to science issues, don't read beyond headlines, succumb to confirmation bias, take up sides and arms in specific camps, and carry our message around to anyone who'll listen without listening ourselves.
Similarly, where we put our money influences who has power and amplifies their message, even if it's not backed by science. We put our money where those opinions are, and those opinions are influenced easily. The industries and companies we support grow, even as we look elsewhere in the world for examples of healthy living. Those companies in turn export our lifestyle into new markets. Unless there's strength in the food traditions in those markets, they become more like us and suffer the same illnesses we do. In the process, they lose the very things we could learn the most from.
So What Can We Do?
By now it may seem like we're pretty screwed. Where can you turn for legitimate advice? I asked our panel for their suggestions, and unfortunately they all agreed that we have to properly calibrate our bullshit detectors, and seek out multiple, trustworthy resources. Be ready for conflicting data — if you find it, it jut means the topic isn't settled. The image above, from this pocket guide to bullshit prevention over at io9, is a good starting point.
You could ask your doctor, or a nutritionist — but Patel explained that's not always the best route. Most physicians get minimal nutrition training during medical school. A "nutritionist" could be anyone with a range of certifications, some of which can be earned in months without any real science study or knowledge.
When I asked Patel, he suggested everyone take time to learn about nutrition science and empower themselves:
It's best to learn a bit of basic nutrition science (like from a free online course or book — online courses form Udemy, Khan, MIT, etc), and then get to finding people who seem logical to discuss things with. These people can be at a local meetup, they could be a doctor or an alternative medicine practitioner or a dietician. Do not rely on Mayo Clinic, WebMD, etc. They are very conservative and go with whatever the government says for the most part. People who like food, who like cooking in particular, often eat healthy even if they don't know everything about nutrition. This is because eating plants and animals is probably the healthiest diet, rather than eating mostly packaged foods comprised of some type of flour, some type of vegetable oil, and a long list of other ingredients.
Bellatti suggests you be critical, but also don't boil it down to the old adage "everything in moderation." It oversimplifies things:
The basic principles of healthful eating — eat a generous amount of fruits and vegetables, eat as little sugar as possible, prioritise whole foods — have remained unchanged for decades. The issue of moderation is problematic because it sounds good in theory, but it has been so watered down and so co-opted by the food industry that it now means nothing. The food industry loves to use "everything in moderation" to state that all their offerings — no matter how heinous — "fit in a healthy diet." Alas, a diet that includes frozen pizza, sugary cereal, soda, chips, and fast food all in "moderation" quickly becomes a diet where these foods, "in moderation," take up the most real estate. I urge people to remain curious and open-minded, but also to remember common sense and, whenever possible, read the actual study or seek the opinion of a well-informed individual who is able to understand the studies. Sometimes, a study like "X food lowers diabetes risk by 35%" is based on a study where the servings needed to slash that risk are preposterous.
At the end of the day, the reason why there's so much confusion is because there's too much to be gained by keeping us all confused and looking for guidance. Similarly, the fact that nutrition and health science is difficult and slow doesn't engender much faith from a quick-fix addicted public.
The big lessons here though are ones you probably knew already: Eat smart, cook your own food, and think critically when someone tries to sell you a diet or lifestyle. Think just as critically when someone is trying to sell you fear, uncertainty, and doubt. Do your own research, challenge your confirmation bias, and be willing to change your mind as new evidence arises (don't fall for the "I've done this my whole life and I'm fine" excuse.) Finally, and most importantly, remember that what works for you may not work for someone else. Nutrition is never a one-size-fits-all science.
Kamal Patel is the director of Examine.com. He's a nutrition researcher with an MPH and MBA from Johns Hopkins University, and is on hiatus from a PhD in nutrition in which he researched the link between diet and chronic pain. He has published peer-reviewed articles on vitamin D and calcium as well as a variety of clinical research topics. Kamal has also been involved in research on fructose and liver health, mindfulness meditation, and nutrition in low income areas. Examine.com and Kamal are both on facebook.
Beth Skwarecki is a science writer and educator. Her work has appeared in Scientific American, PLOS Public Health Perspectives, and the Pittsburgh Post-Gazette. You can find more of her work in her portfolio here.
Beth, Andy and Kamal graciously volunteered their expertise for this story, and we thank them.