You’ve been hearing for decades that it’s a good idea to cut back on red meat. But a controversial studyTrusted Source, released last week in Annals of Internal Medicine, turned that long-standing advice on its head and started a contentious debate.
It found no statistical evidence that eating less red or processed meat will provide health benefits to an individual.
The flip-flopping of nutritional advice is nothing new. Eggs, fat, coffee, and even chocolate have gone from bad to good and sometimes back again. The volleying is enough to confuse anyone.
How can you avoid getting whiplash from health advice that seems to change almost every day?
And more importantly, how do you know what you can trust?
If news on nutrition leaves you perpetually confused, you’re not alone.
A 2018 survey of 1,009 Americans found that 80 percent of respondents came across conflicting advice on nutrition, causing 59 percent to doubt their dietary choices.
“When new research comes out, it’s fascinating and compelling — but people don’t realize that research evolves constantly and there’s no endpoint to it,” said Kris Sollid, a registered dietitian and senior director of nutrition communications at the International Food Information Council, which published the survey.
While researchers are constantly trying to figure out the effects of food on the human body, nutrition science isn’t cut and dry.
“There are a lot of things you can’t control for in studies,” said Lauri Wright, a registered dietitian nutritionist and spokesperson for the Academy of Nutrition and Dietetics.
“Are participants really being compliant to a particular diet, or accurate in how much they reported to eat? There are lots of measurement flaws and problems with memory recalls,” she said.
Even if researchers find a relationship between a health benefit and a particular food or nutrient, it’s difficult to determine whether there’s some other factor (such as a lifestyle choice) that’s also at play.
“People that don’t eat red meat generally have more healthful body weights — that’s an observation,” said Wright. “But people who eat less meat also tend to eat more fruits and veggies, and they may exercise more because if they’re already eating less meat, they’re probably already concerned about their health.”
Controlling for all of these factors is practically impossible in any one study. But when data collected in a variety of ways over a long period of time shows consistent findings, experts can be more confident in making specific recommendations.
Just because nutrition research comes with its challenges doesn’t mean we shouldn’t take it seriously.
Studies give experts clues as to what’s potentially helpful or harmful in our diets. However, the latest findings need to be put into context before people start making changes to their diet.
“Just because conclusions come out in one decade to limit consumption of something to a certain amount, and then another decade we say it’s OK to have more, doesn’t mean we were wrong a decade ago. It means that we’ve learned over the course of time that right now, this is where the evidence stands,” said Sollid. “The nature of research is that we’re constantly learning and people are always looking for answers.”
Few (if any) individual nutrition studies can provide hard and fast rules on the best way to eat. Rather, a culmination of research provides experts with the findings they need to make evidence-backed dietary recommendations.
“Science moves at a very slow pace, which is outpaced by people’s ability to get information in this day and age, and their desire to make changes to their own diet and routine,” said Sollid.
“It’s important to view any new study critically and not base major changes to your diet on any single study,” he added.
Whether it’s the latest research on red meat, or surprising findings on another food, newsy information on nutrition that conflicts with advice you’ve been hearing for many years should be taken with a grain of salt.
“If it sounds too good to be true and it’s flying in the face of consistent evidence, then be skeptical. Don’t make big changes in your habits based on just one study,” said Wright.
Instead, use long-standing research on nutrition to support what you put on your plate.
Focus on lean proteins, eat an abundance of fruits and vegetables, limit how much sugar and processed foods you eat, and pay attention to your hunger cues to avoid overeating, said both Sollid and Wright.
“What we know about nutrition science and its impact on health really hasn’t changed that much in 30 or 40 years,” said Sollid. “You’ll get spikes of certain things that are seemingly interesting, but if you look at the long view, the basic principles still hold true.”
And while the jury’s still out on how much red meat (if any) is safe, no one’s arguing that people should chow down on more burgers and steaks than they’re already eating.
“[The study authors] just said there’s insufficient evidence to make a recommendation to decrease meat consumption,” said Sollid.