Like many topics, nutrition is in the midst of an information glut. Articles, blog posts, journal papers, documentaries, vlogs, podcasts, books, talks, TV shows, radio broadcasts and social media tirades flood the internet at an astonishing rate, and there's no sign it's slowing down. This is a good thing--the average person can access the knowledge and insight of the average scientist in seconds. But it does have downsides too.
Jane used to be incredibly active. She ran, cycled, walked, swam and lifted. Nowadays, she is less active. Her social calendar is full, her grandkids are more energetic than she ever was, and when she does have time to run or cycle or swim, her old injuries cut her sessions short. To counteract her lowered activity levels and advancing age, Jane decides to become more mindful of her nutrition. So she heads online.
She reads about the thirty essential anti-aging vegetables. She reads about how fresh fish can give women "glowing, vibrant skin". She reads about the best herbs from South America and the best spices from Asia. She reads about anti-inflammatory diets and low-carb regimes. She reads about an eighty-year-old who, after one year of a high-protein, intermittent fasting diet, can do ten push-ups in a row (which is nine more than ever before).
It's too much. She could spend the rest of her life assembling a list of the things she absolutely must eat and absolutely has to do to preserve and enhance her health.
She tries the opposite approach and searches for things to avoid. She reads about killer grains and carcinogenic fats. She reads terrifying tales of the digestive havoc that red meat, white meat, meat alternatives, fibrous vegetables, bread and beans can wreak. She comes across a list of "dangerous nutritional behaviors" that includes eating too early, eating too late, eating after exercise and eating before exercise--so when can I eat? she wonders. She goes on to read about the hazards of eating too slow, eating too fast, eating overcooked food and eating undercooked food.
Once again, she feels overwhelmed. At this point, Jane no longer has any idea of what she should eat or when she should eat it or why. But Jane is strong and determined. Perhaps she is over-complicating it?
She searches for nutrition hacks and easy tricks. Links fill up her screen. She reads about simple foods, superfoods and foods that are powdered, requiring only water. In her quest to discover simple actions, sites try to sell her supplements, programs and memberships. After navigating away from that she listens to people who claim to expose the propaganda and malpractice of food corporations, farmers, independent bakeries and artisan restaurateurs.
Jane is almost at her limit. But she has one last attempt in her. Surely the experts won't let her down? She navigates to Google Scholar and pauses. She wants to find a simple answer to a simple question. She recalls the advertising from her youth that demonized products like butter and promoted alternatives like margarine. She types, "Are saturated fats bad for me?" In less than a second has an answer: "Yes. And no."
One study claims there is a correlation between excessive saturated fat consumption and coronary heart disease. Another claims to have found that, in the studied population, saturated fats actually lower the accepted markers for CHD risk. Yet another claims that the saturated fat in butter has altogether different effects from the saturated fat in meat, but declines to offer prescriptions and recommendations for consumption.
Jane, utterly confused, logs off.
RESEARCH AND REPORTING
The problem that Jane, and many others, run into is twofold.
First: scientific research is complex and can usually only prove correlation between a variable and an outcome. It can, for example, detect a link between chocolate consumption and heart disease, but it can't definitively say that eating chocolate will or won't lead to heart issues. To do that, to prove causation, study participants need to be randomized and there needs to be a control group to contrast with the participants receiving the intervention. Also, proving causation usually calls for large sample sizes to be monitored over long periods of times.
Randomized controlled trials involving lots of people over a long period of time are the gold standard. But they don't happen often. And in the presence of other confounding variables (socioeconomic status, activity levels, education, gender, genetics, lifestyle habits, biases arising from study methodologies) it's unclear how much they could actually prove anyway. People eat complex diets and lead messy lives. It doesn't aid scientific research, but it's true.
Second: the reporting of scientific research is confusing. In an ideal world, the only thing any media outlet would care about is providing accurate information to its audience in an honest and unbiased way. Many media outlets do try to do that, but reality intrudes and often makes this only a secondary priority. The main priority of a newspaper is to sell papers; the main priority of a media site is to accumulate page views or subscriptions. A media outlet can't produce media if it can't pay its staff or cover the cost of its overhead. The result? Many stories that emphasize the sensational instead of stories that are balanced and modest in their claims; scare-mongering marketing tactics and fear-inducing headlines; the reworking of common-sense notions, with the help of some cherrypicked data, into alarming conclusions; the omission of important information that moderates findings in favor of bold and sweeping statements.
QUESTIONS AND RULES
Research is complex and the media reporting around it is confusing at best and untrustworthy at worst. So what options does the average person, like you or me, have? That depends on how much time and energy we have available. If we have a fair bit of time and energy we can...
1) Ask specific questions.
Imagine you read a sensational headline: Why You Should Never, Ever Drink Coffee on an Empty Stomach, for example. To assess the strength of its claims you need only ask a few questions:
- Where is it coming from? (A newspaper? A legacy media website? A scientific journal? An anonymous blogger?)
- Is it based on a single study, many studies, or none at all? (Single studies are often contradicted later. A claim based on numerous studies is more robust.)
- Does it involve humans or animals? (Studies aren't always conducted on humans, and it often isn't clear whether the results from animals generalize to humans.)
- Who paid for it? (Studies are often funded by companies with particular interests and ambitions. Nestlé and Mars have funded many studies about the health benefits of cocoa and chocolate, for example.)
- Who benefits from it being true? (You can learn a lot about a study's veracity by figuring out who benefits from the claims being true and widely adopted.)
If you don't have the time to rigorously interrogate an article, however, there is an alternative.
2) Rely on general rules.
There are many possible rules of thumb which you can use to navigate the media environment around nutrition. Too many to list, in fact. But here are a few of my favorites.
- Ignore "breakthroughs", "miracles", and "revolutionary" products and findings (Nutrition is a conservative science: breakthroughs are rare and miracles don't happen.)
- No foodstuff is absolutely good or absolutely bad. (Generally it's the dose that makes the poison.)
- Pay attention to "modest" claims and "boring" findings. (These will be reported on with greater impartiality and less emotion.)
- Read primary, not secondary, sources. (Don't just read the story. Click the link and read the research, or at least the abstract. You'll be surprised at how often there is a difference.)
Utilizing those four heuristics alone will save you a lot of time and energy. Imagine what else you can read if you opt to ignore breakthroughs, miracles, the things you should "always" eat and the things you should "never ever" consume!
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Unfortunately, you can spend the rest of your life reading about nutrition and still not learn all there is to learn. But that is no cause for alarm because it seems that the advice that prevails hasn’t changed much over the past few decades.
A diet that includes a wide variety of nutritious foods from each of the food groups in amounts that balance calories; regular physical activity; moderate alcohol consumption; moderate amounts of sugar; getting enough sleep. These are the things that used to matter, and these are the things that new science is telling us will continue to matter.
But if you must read about nutrition in the media, be savvy: ask specific questions and develop a few rules of thumb to help you navigate the crazy labyrinth of research and reporting.