The amount of misinformation that has flourished on social media sites has reached “critical levels,” said Christopher D. Gardner, director of nutrition studies at the Stanford Prevention Research Center and chair of the committee that authored the report.
“The public and many medical professionals are probably confused about heart-healthy eating, and rightly so,” he added. “Many of them probably feel they don’t have the training or the time to assess the important features of different diets.”
Ranking diets for heart health
The report, published Thursday in the journal Circulation, was written by a team of nutritional scientists, cardiologists, dietitians and other health experts, who analyzed a variety of diets.
The diets were assessed to see how well they aligned with heart-healthy eating guidelines, which are based on evidence from decades of randomized controlled trials, epidemiological research and other studies. The report also considered factors such as the flexibility of the plans so that people can adapt them according to their cultural and personal preferences and budget constraints.
The heart association’s guidelines include tips for eating a wide variety of fruits and vegetables, whole grains like brown rice, bulgur, and steel-cut oats, as well as lean cuts of meat and foods like chicken. olive oil, vegetable oils and seafood, which are high in protein and heart-healthy omega-3 fatty acids.
The group recommends limiting foods that are salty, sugary, highly processed, or made with white flour and other refined grains. These include things like soft drinks, white bread, white pasta, cookies, cakes, pastries, and processed meats such as hot dogs, sausages, and deli meats.
As for alcohol, the evidence that it provides cardiovascular benefit is questionable. The Heart Association says people who don’t drink shouldn’t start, and if you do drink, you should limit your intake.
Popular low-carb diets had the lowest scores
The Heart Association has given its lowest rating, on a scale of 0 to 100, to some of the most popular diets widely touted on social media. These included very low-carb diets like the Atkins and ketogenic diets (31 points) and the paleo diet (53 points).
Following such diets usually requires limiting your carbohydrate intake to less than 10% of daily calories. The diets are widely promoted for weight loss and endorsed by many celebrities.
“People are so carb-phobic, and that’s one of the things you see on Instagram — that carbs are bad,” said Lisa Young, an assistant professor of nutrition at New York University, who doesn’t did not participate in the report. “But this is misinformation. Fruits, vegetables, legumes and whole grains are good for you – they are healthy carbs. These foods are the cornerstone of a healthy diet.
The report notes that the Atkins and keto diets have some beneficial characteristics: they limit sugar and refined grains, for example, and they encourage the consumption of non-starchy vegetables like broccoli, asparagus, leafy greens and cabbage. flower. But they usually require limiting lots of “healthy” carbohydrates that align with the Heart Association dietary principles, such as beans, whole grains, starchy vegetables, and many fruits. And they usually include a high intake of fatty meats and foods high in saturated fat.
Some studies have shown that very-low-carb diets can help with weight loss and improve certain markers of metabolic health, like blood sugar and triglyceride levels. But the Heart Association report noted that these improvements tend to be short-lived and that very low-carb diets often lead to increased LDL cholesterol levels, which can increase the risk of heart disease.
The report found similar issues with the paleo diet, which excludes grains, vegetable oils, most dairy products, and legumes such as peanuts and soy. The theory behind the diet is that it allows foods like fruits and honey that our hunter-gatherer ancestors had access to, but excludes grains and other foods associated with modern agriculture.
The diets have also been criticized for what is often interpreted as an all-you-can-eat stance toward red meat, from steaks and burgers to bacon and processed deli meats. TikTok’s “Liver King,” for example, gained popularity for advocating a controversial, meat-heavy “ancestral” diet made up largely of organ and muscle meats.
The low ranking of the ketogenic and paleo diets is expected to spark controversy. In 2019, three doctors published an essay in JAMA Internal Medicine warning that enthusiasm for the ketogenic diet exceeded science. The research was polarizing, generating a flood of emails of support and condemnation.
Colette Heimowitz, vice president of nutrition and education at Atkins, said the new report doesn’t properly describe the Atkins diet, which includes three approaches with different carbohydrate limits.
One approach, which is generally used in the short term for weight loss, allows only 20 grams of carbohydrates per day. Another version of Atkins allows 40 grams of carbs per day, and the third approach allows people to have up to 100 grams of carbs per day, including small amounts of fruits, starches, beans, and grains. whole. “Evidence suggests that Americans have varying tolerances for carbohydrate loads,” Heimowitz said. “So carbohydrate-focused diets like Atkins have never been more relevant.”
The four winning heart diets
The heart association gave its highest rating – a score of 100 – to the DASH eating pattern, which stands for “Dietary Approaches to Stop Hypertension.” Developed by National Institutes of Health researchers in the 1990s, the DASH diet is widely endorsed by doctors, dietitians, and other nutrition experts.
But it’s not really trending among celebrities and social media influencers. The diet emphasizes vegetables, fruits, whole grains, beans, legumes, nuts, seeds, and low-fat dairy products, while encouraging people to limit their intake of salt, fatty meats, added sugars and refined grains.
The DASH diet and three others with high scores were grouped into what the heart association called Level 1. Others in the Level 1 group included the pescatarian diet (92 points), the Mediterranean diet (89 points) and the vegetarian diet (86 points). ).
Although these diets have small differences, they also share some common denominators – promoting fresh produce, whole grains, beans and other plants and whole foods. The pescatarian diet is similar to the vegetarian diet, but it allows seafood. The Mediterranean diet promotes moderate consumption, while the DASH diet allows alcohol but does not encourage it.
“The conclusion we came to between these diets is that they’re all good and very consistent with a heart-healthy diet,” Gardner said.
Gardner pointed out that the report judges diets by how they are “intended” to be followed, not necessarily by how some people actually follow them or interpret them.
For example, a vegetarian can drink Coca-Cola and eat potato chips and McDonald’s Egg McMuffins for breakfast. It’s a vegetarian diet, but not exactly a heart-healthy vegetarian diet, Gardner said.
“That’s not what we have in mind when we say people should follow a plant-based diet,” he added. “I know from these studies that people don’t always follow diets the way they want to: they follow them based on misinformation.”
The report included two other levels of diets. Vegan and low-fat diets have been grouped into the second tier because they encourage the consumption of fiber-rich plants, fruits, and vegetables while limiting sugary foods and alcohol. But the report notes that they are quite restrictive and can be difficult for many people to follow. The vegan diet, in particular, may increase the risk of developing vitamin B12 deficiency and other problems.
The third tier of diets received the second lowest score range. This group included low-carb approaches like the South Beach and Zone diets, which limit carbs to 30 or 40 percent of daily calories, as well as very low-fat diets like the Ornish, Esselstyn, and Pritikin, which limit fat. intake less than 10 percent of daily calories.
These diets received lower scores because they limit or eliminate a number of healthy foods, according to the report. People on a low-carb diet, for example, tend to eat less fiber and more saturated fat, while people on a very low-fat diet should reduce all types of fat, including healthy unsaturated fats. present in olive oil, avocados. , nuts and seeds.
Although some diets scored low, the report found that all diets in each tier had four positive points in common: they encouraged people to eat whole foods, more non-starchy vegetables, less added sugar and less refined grains.
“If we could get Americans to do these four things, it would go a long way toward ensuring everyone had a healthy diet,” Gardner said.
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