Food for Thought: Experts Chew on Diet Fails

01/30/2020
By Karen Angelo

As the month of January rolls by, New Year’s dieting promises tend to fizzle out. Many people who’ve resolved to follow the latest fad diet, such as keto, paleo and flexitarian regimes, find themselves back where they started by the time February arrives. 

Studies show that for a majority of people, the weight piles back on in the long term. The reason? The restrictions of one particular diet are too difficult to stick to. 

Assoc. Teaching Prof. Renee Barrile of the Department of Biomedical and Nutritional Sciences, a registered dietitian, says that the best way for most people to keep the weight off over the long term is to find flexible ways to eat healthy. 

“By finding strategies that fit with your lifestyle rather than adhering to the latest fad, you’ll set yourself up for success,” says Barrile, who previously worked at Massachusetts General Hospital’s weight management center. 

Mary Kate Keyes, a clinical instructor in the Department of Biomedical and Nutritional Sciences who is also a registered dietitian, says that it may help if people think of the word “diet” as a description of what we eat every day, rather than referring to a particular restrictive eating regimen. 

“While some people do great on commercial programs like Weight Watchers, the mindset is that I’m either ‘on’ a diet or ‘off’ a diet,” says Keyes. “The best way to live is somewhere in the middle – not restricting and not indulging at every meal, every day.” 

She also recommends combining healthy eating with exercise. 

“Exercise is crucial, not only for cardiovascular health but for stress management, better sleep, strength, injury prevention and self-care, which can support efforts to eat healthier,” she says. “The best exercise is the exercise you enjoy. It should not be a punishment, but rather something you can manage and feel great doing.” 

In the undergraduate course Obesity and Weight Control that Barrile teaches, students review literature and analyze the science to see which diets work and don’t work. 

Nutritional Sciences majors Katherine Pittsley and Kyle Mehan learned that weight loss is different for everyone. 

“This class taught me that due to the differences in the way people's bodies function and how they act, their particular physiology and their food choices, there is no one-size-fits-all approach to losing weight,” says Mehan, who plans to earn a Master of Public Health in dietetics. 

“Most fad diets are ineffective or even dangerous,” he says. “Some trendy diets are focused on one or two valid physiological mechanisms or health principles, but they have many blind spots.” 

Pittsley says that she now understands how improving and maintaining mental health is an important factor to losing weight. 

“We learned that stress can encourage weight gain,” says Pittsley, who plans to enroll in the Master of Public Health dietetics program in 2021. “A good weight loss program should always be multifaceted, including face-to-face meetings with a dietitian, which fosters a sense of support and accountability, stress management tools and possibly referrals to a trained mental health professional.” 

The Lowdown on Fad Diets 

Even for the diets that are backed by some science, like keto and veganism, the weight loss doesn’t last for a majority of people because it’s hard to maintain. 

“Most people lose weight in the short term probably from water loss,” says Barrile. 

Other diets like paleo – which restricts grains, legumes and most dairy – are not based on science or reality, since our food system has changed since humanity’s caveman days. You may lose weight temporarily, but it’s tough to maintain this way of eating forever. 

The most recent trend of intermittent fasting has gained attention, but there is no research to support that fasting works better than other weight loss strategies. 

Veganism can be healthy but needs to be carefully planned, according to Barrile. Unfortunately, the food industry has introduced vegan junk food. 

“A veggie burger used to be made with beans, mushrooms and soy protein. Now we see processed veggie burgers sold in fast-food restaurants,” says Barrile. 

Lasting Weight Loss Strategies 

Research backs the long-term success of a Mediterranean-style diet, which is rich in whole vegetables, fresh fruits, whole grains, fatty fish, olive oil, nuts and legumes. Studies show that people who followed the diet kept the weight off after six months. 

UML experts recommend using the Mediterranean-style diet as a guideline that you integrate into your life. Other strategies may include these efforts: 

• Eat less processed foods. When foods are processed – or worse, ultraprocessed like frozen meals and sweetened cereals – they taste so good that it can be hard to stop. However, these foods are stripped of a lot of their nutritional value, so we fill up on empty calories. 
• Choose minimally processed foods that make you feel energized and that you enjoy. Examples include cut vegetables, roasted nuts and bagged spinach. 
• Don’t drink your calories. Eliminate sweetened coffee drinks and soda. Cut back on alcohol. 
• Reduce consumption of hidden sugars in foods such as ketchup, crackers and yogurt. Always read labels. 
• Eat more healthy fats, proteins and vegetables rather than white bread and pasta. 
• Don’t snack after dinner if you have trouble limiting yourself. 
• Fill half of your grocery cart with fruits and vegetables. Shop the outer aisles of the grocery store to start; that’s typically where the fresh and healthy frozen foods are. Then dive into the inner aisles, where processed foods are stocked, and restrict your purchases there. 
• Practice patience! The road to improved health can be long and littered with setbacks, but with time, positive changes will come. 

When to See a Registered Dietitian Nutritionist 

A recent study published in the New England Journal of Medicine says that about half of the adult U.S. population will have obesity, and about a quarter will have severe obesity, by 2030. Whether you’re headed in this direction or not, meeting with a registered dietitian nutritionist (RDN) will help you understand how your body functions and therefore make it more likely that you’ll make lasting dietary changes. 

“Registered Dietitian Nutritionists are a great resource for anyone who is interested in learning more about how to fuel their body,” says Keyes. “Consider seeing an RDN when you have a suspected allergy or intolerance, or if you're managing a chronic disease like obesity, diabetes or heart disease.” 

Mehan has investigated how individual variables such as genetics, lifestyle, culture and psychology affect weight loss. 

“It can be an intimidating task to evaluate all of these factors, but this is why registered dietitians exist,” he says. “They have the knowledge to identify and address individualized weight issues and work with a patient or client to tailor lifestyle changes that they can actually attain.”