Recently we sat down with Dr. Erin Glynn, member of Unicity’s Scientific Advisory Board (SAB), to tackle a common question: are diets effective? In this Q&A, Dr. Glynn breaks down the science behind what makes diets most effective for long-term weight management.
What is the best diet for weight management?
There’s a saying “The best diet is the one you’ll stick to,” and there is some truth in that. Diet is, and should be, personal. We all have different needs and preferences when it comes to food. The science shows you can successfully lose weight on a variety of eating patterns or “diets,” as long as you are in a calorie deficit—consuming less calories per day than your body needs. You want to choose a way of eating that you enjoy and can sustain long term for the best success.
For most people, this means focusing on a plan that allows for variety, reasonable levels of all macronutrients (carbs, protein, and fat), and flexibility over strict rules and elimination of entire food groups. For these reasons, approaches like the Mediterranean Diet, a 40/30/30 distribution of carbs/fat/protein, and intermittent fasting are all great options.
Is any diet sustainable long term?
Yes, they absolutely can be, and that’s the goal: to identify a healthy eating pattern that is sustainable for you. Very restrictive approaches like a ketogenic diet or being fully vegan are challenging for most people to stick with long term. Balanced approaches like the Mediterranean Diet, or intermittent fasting—which can include a variety of eating patterns, but is more focused on the timing of food intake—allow more flexibility for people, which improves long-term success.
Why does Unicity recommend controlling carbs and getting enough protein?
Most Americans are eating too many carbohydrates, particularly simple carbohydrates that are known to spike blood sugar levels. Controlling carbs is not about demonizing them, but rather learning about the effects of simple carbohydrates on your blood sugar, and then making smarter choices to choose complex carb sources from whole foods like vegetables and whole grains.
Protein is critical for weight management. It’s very satiating, so aiming for at least 20 grams of protein at each meal (preferably more!) will help keep you full between meals. Protein also helps build and repair muscle, which is important to prioritize on any weight-management program. Although the current recommended dietary allowance (RDA) for protein is 0.8 grams per kilogram body weight per day, most experts agree this is low, and suggest 1.2–1.6 g/kg per day instead. Prioritize getting a good serving of high-quality protein at each meal to hit this goal.
What types of carbs should I stay away from?
All carbohydrates aren’t bad, but there are definitely types and sources of carbohydrates that support health and others that don’t. As a general rule, we want to stay away from refined and simple carbohydrates found in processed foods, enriched/white flour products, white rice, syrups, candies, and sweets. These types of carbohydrates typically spike blood sugar, which can make weight management harder (more hunger, cravings, irritability, etc.).
Is it better to eat the majority of carbs earlier in the day or should I spread them out?
Research shows insulin release from the pancreas has a circadian rhythm, slowing down later in the evening. This is one reason it is advised not to eat late at night. Enjoying complex carbohydrates at any meal with plenty of fiber, protein, and healthy fat to help reduce the impact of those carbohydrates on blood sugar is fine. You want to be more conscious of consuming any simple carbohydrates like from white pastas, breads, or rice later in the day.
Why is fiber so important for weight management?
Fiber helps to slow the rate of digestion during meals, which can slow how quickly carbohydrates from a meal raise blood sugar. Keeping blood sugar levels more stable throughout the day helps keep energy levels steady and reduce hunger and cravings. Similar to protein, fiber can promote satiety, helping you feel full between meals so you can stay on track with your nutrition plan.
What role does intermittent fasting play in a healthy diet?
Intermittent fasting, particularly a time-restricted eating approach like 16:8, can naturally help people eat fewer calories in a day. Studies show eating in a shorter window can reduce daily calorie intake by about 425 calories. Placing the eating window in the main part of the day also helps reduce late-night snacking and meals, which greatly helps with both metabolic health and weight management.
There are numerous benefits of intermittent fasting for health, but helping to control calorie intake and promote less late-night eating are two that have a large impact on maintaining a healthy weight through diet.
About the author: Dr. Erin Glynn is a member of the Unicity Scientific Advisory Board. She received her bachelor of science degree in exercise physiology from Texas A&M University, followed by her Ph.D. in preventive medicine and community health from the University of Texas Medical Branch. She completed a postdoctoral fellowship at Duke University Medical Center, where she focused on the metabolic profiling of metabolic diseases, including obesity and diabetes. Dr. Glynn is an active member of the American Society for Nutrition and the host of the Nuchi Health Podcast, which discusses health, nutrition, and general wellness topics from a scientific perspective. You can find Nuchi Health on social platforms @nuchihealth or listen to the podcast on most major platforms.