As a new year dawns and we try to recover from a 2016 hangover, many of us will be reassessing our diets, health, and waistlines. It’s an annual tradition that naturally follows indulgent holiday feasting. But, after many spent the year stress-eating, our 2017 resolutions may be our firmest yet… maybe.
So, what did we learn from researchers in 2016 that we could apply to our totally firm 2017 diet and health resolutions? Plenty. Some of it is even useful.
Like any year, 2016 served up a heaping pile of low-quality nutrition studies and forehead-slapping dietary advice and headlines. Federal dietary guidelines, meanwhile, got their five-year reboot and remained largely unchanged. Yet, there were some illuminating revelations to keep in mind as we chew over our diet choices. Most notable of those is the extent to which the food industry has been messing with our minds—and our research. Plus, 2016 saw some scientific insights into why dieting doesn’t reliably pan out.
It’s easy to forget about dieting failures when you’re reading optimistic and declarative media reports on nutrition research. 2016 kicked off with headlines proclaiming that just eating more berries will keep you from packing on pounds. That takeaway came out of a study looking for associations between weight and diet in large cohorts—a common type of study that doesn’t determine causation. In this case, the study’s findings backed up the well-established fact that fruits are part of a healthy diet but didn’t convincingly show that berries or other high-flavonoid foods were particularly beneficial for weight loss.
Around the same time, FiveThirtyEight demonstrated the problems with such correlative studies by doing their own. They found “statistically significant” links between eating egg rolls and owning a dog, drinking ice tea and believing that Crash didn’t deserve to win the Oscar for Best Picture, and eating fat-trimmed steaks and being atheist.
That demonstration, of course, didn’t stop the usual parade of similarly silly headlines the rest of the year. Just this month, headlines teased the question of whether drinking white wine causes skin cancer—the answer: no, no it doesn’t. Though drinking alcohol has been linked to increased risks of some types of cancers (melanoma not generally included), the new study is again just a correlation and has flaws. The reported link was likely a statistical fluke.
And then there’s the analysis from this month that found that eating nuts every day cuts risks of cardiovascular disease, cancers, and dying early. If only avoiding those conditions were that easy…
In addition to weak correlations being turned into causations, the field of nutrition research also tends to be marred with plain old weak studies. And that didn’t change this year. For instance, a study from August led to headlines suggesting that the Paleo diet could cut a person’s risk of cardiovascular disease. Yet it was based on eight people. Another alarming study suggested that common food preservatives cause cancer. That study was based only on mouse experiments in which the animals were fed extreme amounts of preservatives and given drugs to induce cancer.
Tipping the scales
Unfortunately, poorly designed and reported nutrition studies aren’t the only pitfalls of the field—or even the worst. This year, we became more aware of the undue influence of the food and beverage industry on nutrition research—upping the level of skepticism necessary in an already fraught area of research.
In a September piece from JAMA Internal Medicine, Harvard researchers revealed that sugar industry executives paid researchers big bucks in the 1960s to downplay the role of sugar in heart disease. Instead, the blame went almost exclusively to fats. The clandestine meddling skewed decades of federal dietary guidelines and may have helped set the stage for the sugar-fueled rise of obesity.
Taking a page out of the sugar industry’s playbook, Coca-Cola Company and PepsiCo have also been quietly funding dozens of national health organizations, according to a research article that the American Journal of Preventative Medicine published in October. The authors—researchers from Boston University—linked soda-funding to decisions by health organizations that served the interest of their funders, not their patients. For example, the Save the Children charity abruptly halted support of soda taxes after receiving hefty grants from soda companies.
The October revelation follows an investigation by The New York Times in 2015 that exposed financial ties between Coca-Cola and a network of nutrition researchers who tried to shift focus away from the role of sweetened beverages in obesity and instead promoted the benefits of exercise.
Despite the exposure, the food industry seems unruffled. On December 19, a review published in Annals of Internal Medicine drew quick criticism for its blatant ties to the sugar industry. The review fiercely argued that the dietary advice to cut sugar is based on weak or untrusted evidence. (It’s not.) As The New York Times pointed out, the review was funded by the International Life Sciences Institute, a scientific group supported by food and agrochemical companies including Coca-Cola, Hershey’s, General Mills, Kraft Foods, Kellogg’s, and Monsanto. And one of the review’s authors is a member of the scientific advisory board of Tate Lyle, one of the world’s largest suppliers of high-fructose corn syrup.
Made to order
While health researchers can safely agree that excess sugar leads to problems—as does the food industry’s interference with research—there’s still hand wringing over diet recommendations.
In this year’s update to the federal dietary guidelines, experts advised people to load up on “vegetables, fruits, grains, low-fat and fat-free dairy, lean meats and other protein foods and oils, while limiting saturated fats, trans fats, added sugars and sodium.” While the broad recommendations describe a healthy diet, they leave a lot of room for interpretation in terms of daily food decisions. And they’re not particularly helpful in guiding people on how to lose weight or improve specific aspects of their health.
Plenty of diet theories and plans fill that void—Paleo, Atkins, GOLO, Mediterranean, raw food, etc. For some people, those diets won’t work or only work in the short-term. For others, they will work long-term. And, as a recent NYT article explored, researchers aren’t clear on why exactly. But what is becoming clear is that diets really aren’t one-size-fits-all.
“You can look at two people with the same amount of excess body weight, and they put on the weight for very different reasons,” said Dr. Arya Sharma, medical director of the obesity program at the University of Alberta, told the Times. Current diet, genetics, exercise levels, medications that promote weight gain, stress-levels, bad eating habits, and more can contribute to health problems and weight gain, researchers are now noting. And those different problems require different remedies to take weight off and keep it off.
Instead of following the latest fad diet or nutrition headlines for your 2017 diet resolutions, experts recommend trying to first identify causes of your health problems or weight gain—such as not noticing how much soda you drink while sitting at your computer, always feeling hungry or having cravings due to medications you’re on, not keeping track of what you’ve already eaten in a day, or not getting enough exercise. With the help of a doctor, you can try out different strategies to address specific problems until you find a strategy that works long-term. Those strategies could include new diets, weight loss medications, exercise plans, new sleep schedules, or, for some, bariatric surgery.