Dietitian breaks down the science, sifts through the myths, and offers a different way to think about food

Editors’ notes

With so many types of diets being promoted online and on social media, a leading dietitian says flexibility is more sustainable than a rigid diet plan.

Joyce Patterson, MPH, RDN, BC-ADM, CPT is a registered dietitian and a diabetes care and education specialist at Michigan Medicine in Ann Arbor, U.S., and she says the science points to a balanced approach.

“We live in a world full of messages to restrict, eliminate, and fast, and misconceptions related to diet trends are common, such as macronutrient or supplement needs,” she explains. “For example, the war wages on over fats versus carbs, or eggs come in and out of favor every couple of years, and the media and food manufacturers exploit such information to drive what people think about nutrition to increase sales.

“The sheer number of products and programs claiming to ‘reset your metabolism’ or ‘cleanse’ your system indicates that many people are indeed interested in the science. But few receive comprehensive and reliable nutrition education and are unable to discern between marketing ploys and good science. They are making food choices and purchase decisions based on minimal or misleading information.”

What are some diet trends?

In her new book, “Think Like A Dietitian,” Patterson reviews a variety of diet trends, unpacking the myths around each and where the barriers to success lie.

“For many, diet culture has shaped their relationship with food throughout their lives. From the parental influences of their childhood to the virality of social media today, these beliefs can be deeply ingrained.”

Patterson highlights that many popular diets are based on minimal scientific evidence, but the ketogenic diet and intermittent fasting are highly studied and debated among nutrition researchers and clinicians.

Research cited in the book has shown the ketogenic diet offers short term benefits in rapid weight loss and metabolic disorders including diabetes, but Patterson says there are not enough long-term studies to determine the long-term safety of the regimen.

Similarly, the various forms of intermittent fasting have also shown potential as treatments for obesity and cardiometabolic disorders, but for alternate-day fasting or prolonged fasts, more studies are needed to assess its long-term safety.

“When certain diets show promising findings in research, many well-meaning, non-nutrition clinicians will be quick to recommend these approaches,” Patterson explains. “From low fat to low carb to fasting, the most popular diets are ironically the most restrictive. It is no wonder they tend to be the most unsustainable.”

In ketogenic diets, the initial water loss in the first week alone can show changes on the scale. However, studies also repeatedly show evidence of weight loss in various other eating patterns—regardless of macronutrient composition—without one proving to be more superior to others. In regard to weight loss maintenance, Patterson explains that “research continues to show little difference when comparing various dietary patterns for long-term weight loss.”

What are the issues with diet trends?

“A common practice is that people will apply certain features of a diet, instead of the actual dietary pattern that was researched. Without proper guidance, people may end up practicing unhealthy behaviors that put their health at risk.”

Patterson points out that diet culture can also push people down a path of overly-restrictive eating.

“Not all people push nutrition down the priority list,” she explains. “In fact, some are so aware of their choices that they control themselves straight into hunger. They know their way around a grocery store and leave no package unturned, scanning and comparing nutrition labels.

“While mindfulness is a key tenet in healthy eating, calories and certain food groups have been vilified by diet culture. Whether people are counting calories, carbs, fat, sodium, or other nutrients, the interpretation is often ‘less is more.’ Instead of focusing on healthy food choices and overall balance, some people get caught up in the minutiae of nutrients. They feel food is something to be avoided, as opposed to being the fuel that provides power, strength, and protection.”

Following diet trends can also create an attitude which Patterson calls “all-or-nothing.” She explains: “Many people are pretty savvy when it comes to diet trends. They keep up with the latest trends and are willing to try new things. They become familiar with terms like ‘macros’ or ‘alkalinity’ or ‘ketones.’ When they put their minds to it, they are able to lose weight rather quickly. They know how to slim down for a wedding or a cruise or a beach vacation. When they’re ready, they dive right in and see results.”

However, Patterson explains that when something unexpected happens, such as a social event, a family issue, a health concern, or a stressful event, often these ‘all or nothing’ dieters hit an inevitable plateau, become frustrated, and give up.

“Life happens. And it will happen again and again. These are perhaps the most impactful challenges that people encounter because they are recurring and inevitable. They may be accompanied by an emotional burden such as stress or worry. Or the episode may be followed by feelings of guilt or failure, especially for those whose self-efficacy was low in the first place. If it happens repeatedly, the cost of the effort may seem to outweigh the benefit, leading to a complete cessation of action. All too often, this cycle of regression repeats itself,” she explains.

What should we do instead?

“In my experience, I find that many diet trends are effective not because they are novel, but because they are similar,” Patterson says.

Research and Patterson’s experience both suggest that most diets work because regardless of whether it monitors calories, carbs, fat, protein or points, it usually follows that some of these basics are applied: added sugar and ultra-processed foods are limited; plant foods increase; portions are controlled.

“With every new study, there is a new headline, causing whiplash among patients and health professionals alike,” she explains. “Therefore, erring on the side of balance and variety can be a safe way to maneuver some of these controversial and ever-changing topics.”

Patterson suggests that following an “80/20” rule is more sustainable, acknowledging that dietary perfection is an impractical approach.

“Specifically, this rule of thumb suggests that people follow dietary recommendations 80% of the time, and not to worry about the other 20%, factoring in convenience, enjoyment, and social interactions.

“One of the most important experiences that a dietitian can share is that perfection is not only unattainable but also unnecessary. Even centenarians often admit to some lifelong indulgences.

“A healthy diet does not have to be all-or-nothing. The occasional treat is not harmful. However poor choices in excess can increase risk for nutrition-related disease,” she explains.