Every year it seems a new fad diet is unleashed upon a populace that’s always in search of a dietary cure-all. And the more time that passes, the more we have to choose from.
There’s the paleo diet, which has devotees eating like cavemen — lots of plants and meat, no grains or dairy.
The ketogenic diet greenlights lots of fat, but almost no carbs.
That last fad diet example might better fit the category of “fad lunacy.” But for a time some teenagers actually thought snacking on cotton was a good way to suppress hunger.
One good thing about fad diets is that they get us thinking critically about what we eat. But with seductive promises of rapid weight loss, or body-cleansing or energy-boosting powers, fad diets can also lead to unhealthy obsessions with programs that have tenuous connections to science. In the long run, by eliminating certain food groups and the essential nutrients that come with them, many fad diets can do more harm than good.
About 45 million Americans go on a diet each year. But which fad diets really merit changing your eating habits? And which ones will actually move the numbers on your scale in the right direction?
What Is a Fad Diet?
While there’s no clinical definition, fad diets have several common denominators.
Most are promoted as the best approach to losing weight. Most promise dramatic results quickly. Many cut out entire food groups or advocate intake far above or below amounts recommended by major health organizations. Some focus on one food or group of foods as a miracle solution.
And all fad diets have one thing in common, according to the Cleveland Clinic, one of the nation’s most prestigious hospitals: a temporary solution to what for many people is a lifelong problem.
Why Americans Can’t Quit Fad Diets
Whatever type of eater you are, there’s probably a fad diet out there designed to appeal to you. If not, wait awhile — another one is just around the corner.
Is this because researchers keep discovering new things about the body and metabolism? Or are all the fundamental tenets of healthy eating established, making fad diets all about marketing?
It’s mostly the latter.
“The basic themes of healthy eating have always been the same and probably always will be the same,” says Danelle Olson, RD, LDN, CNSC, bariatric dietitian in the Weight Loss Surgery Center at Beth Israel Deaconess Medical Center in Boston. “Fad diets persist because people are looking for some kind of magic bullet. People are willing to try anything new or different.”
Anna Kippen, a registered dietitian at the Cleveland Clinic’s Center for Integrative and Lifestyle Medicine, agrees: “We all secretly hope that the next new ‘miracle’ diet will come out and give us the key to eating unlimited amounts of our favorite foods on a daily basis. It’s no surprise that fad diets appeal to our most basic desire.”
Fad Diets You Should Avoid
Kippen has a list of red flags she waves at most fad diets. They include:
- Anything billing itself as a magic bullet or quick fix
- Anything that promotes a product that must be purchased in order for the diet to work
- Statements that directly contradict scientific organizations such as the Academy of Nutrition and Dietetics, American Heart Association, and USDA
- Anything that eliminates entire food groups
- Anything that guarantees rapid weight loss
- Rigid menus with little variety
Fasting and “detox” diets
While fasting has been a religious, political, and cultural tradition dating back to antiquity — Jesus’ 40 foodless days in the desert probably make him history’s most famous faster — modern experts caution against depriving the body of food. The significant and rapid weight loss that results is almost always offset by problems that outweigh any perceived benefits.
Although most people can tolerate short-term fasting with only minor issues, such as headaches, nausea, and weakness, complications associated with prolonged fasting include gout, compromised kidney function, abnormal heart rhythm, low blood iron, hair loss, vitamin deficiency, and, in rare cases, death. “Evidence shows that people who lose weight gradually and steadily, about one to two pounds per week, are more successful at keeping weight off,” according to the Centers for Disease Control and Prevention. “Healthy weight loss isn’t just about a ‘diet’ or ‘program,’ it’s about an ongoing lifestyle that includes long-term changes in daily eating and exercise habits.”
Likewise, be wary of body “cleanses” that call for extreme measures. From a scientific perspective, your kidney, liver, and immune system do just fine on their own flushing toxins from the body. That said, “detoxes” are popular in many traditional cultures; they can be empowering mentally; and, frankly, there’s nothing wrong with cutting junk out of your diet, even for a short period. So, if you want to do a cleanse, choose wisely. If the primary push of the plan is a basically just a short period of ultra-clean eating, you’re probably OK.
Exclusion or single-ingredient diets
Severely limiting the variety of foods you eat — or relying on one food like apple cider vinegar to produce miracle results — is always a bad idea. Not only are such fad diets boring, thus harder to maintain, they eliminate vital nutrients provided by other food groups.
The cabbage soup diet doesn’t exclude foods as much as it fills you up with one food to the point that you can’t really eat anything else. It’s a seven-day diet featuring all-you-can-drink cabbage soup with every meal. You’re also not allowed to eat bananas until day four, at which point you need to eat up to eight bananas, then no more bananas until it’s over. The idea here is that you’ll fill up on this low-calorie broth with, apparently, a halftime banana break.
Around in various incarnations since the 1930s, the grapefruit diet is a good example of a single ingredient “miracle” fix. The basic version of the diet involves simply eating half a grapefruit before every meal.
Proponents believe the enzymes in grapefruit can help you burn fat and magically help you lose weight. Trouble is, multiple studies debunk these claims. In 2011, British researchers compared eaters who consumed grapefruit, grapefruit juice, or water before meals. They found no significant differences among the three beyond cholesterol levels… meaning the citrus was on par with water in terms of weight loss.
“Incorporating consumption of a low-energy, dense dietary preload in a caloric-restricted diet is a highly effective weight-loss strategy,” wrote researchers. “But, the form of the preload did not have differential effects on energy balance, weight loss, or body composition.”
Which Fad Diets Work?
If your goal is unsustainable weight loss, most fad diets are good for quickly dropping a few pounds that you’ll just gain back once you fall off the wagon. And then you’ll probably gain a few more on top of that.
If you’re looking for lasting results, not to mention good health, you’re probably not going to find it with fad diets. However, there’s no shortage of smart diet trends that can get the job done. These nutrition strategies are different from fads in that they were either borne from solid science and research or they evolved culturally over decades or even centuries.
The origins of what we now know as the Mediterranean diet — filled with fresh fruit and vegetables, whole grains, olive oil, legumes, nuts, fish, and limited meat — date back to ancient times. But popularization of its health benefits is credited to a Minnesota physiologist named Ancel Keys, who wondered why poor residents of villages in southern Italy were healthier than wealthy residents of New York.
Keys’ landmark “Seven Countries Study” begun in the late 1950s showed “populations that had adopted a diet based on the Mediterranean diet presented a very low rate of cholesterol in the blood and, consequently, a minimum percentage of coronary heart disease,” according to the National Institutes of Health. In 2019, U.S. News & World Report ranked the Mediterranean Diet best out of more than 40 popular diet plans. In addition to research that suggests the diet can help prevent disease and increase longevity, the Mediterranean diet scores points for being easy to follow and delicious.
“I would say the Mediterranean diet is one of my favorites because it’s rich in whole grains, legumes, fruits, and vegetables,” says Kippen. “It will leave your waist smaller and your heart and mind healthier.”
Combining the words “flexible” and “vegetarian,” and sometimes described as a part-time vegetarian diet, the flexitarian diet is built around fruits, vegetables, legumes, whole grains, and plant proteins. It does allow occasionally eating high-quality fish and meat, though only in small quantities.
According to a 2017 report by the National Center for Biotechnology Information, flexitarian and semi-vegetarian diets “could have potential health benefits with strongest evidence appearing to be in relation to weight loss and metabolic health benefits, including reduced diabetes risk and blood pressure.” Says Olson: “We know the best source of protein is from animals, so I appreciate that part of the flexitarian diet.”
Mayo Clinic diet
Developed at the famed Minnesota institute, and based on research and clinical experience, the Mayo Clinic diet is a long-term weight-management program that aims to reshape whole lifestyles by promoting the adoption of healthy new habits.
The Mayo Clinic Healthy Weight Pyramid focuses on unlimited raw vegetables and fruit, whole-grain carbohydrates, lean sources of protein such as legumes, fish, and low-fat dairy, and heart-healthy unsaturated fats.
“The Mayo Clinic diet teaches you how to estimate portion sizes and plan meals,” says the clinic. “The diet doesn’t require you to eliminate any foods.”
Forget “Fad,” Think “Long-Term”
It’s important to remember that “fad” doesn’t denote new scientific breakthrough or metabolic discovery. “Diet,” however, still carries a lot of weight.
“Diets of the moment do get the consumer thinking. And a lot of them encourage many healthful foods and exercise, which is a really important piece of the puzzle,” says Olson.
“A lot of popular media and fad diets out there make us overthink things,” she continues. “We know the most healthful way for us to eat is to include a variety of foods and food groups. Nothing is necessarily off-limits. It comes down to the cliché, ‘everything in moderation.'”