People respond differently to weight loss strategies, but typical studies only test one intervention at a time. UAB’s Drew Sayer is testing multiple strategies in a single study.
Do you lose the pounds while exercising or do you get so hungry that you only gain weight? Are you one of those people who would benefit from a high-protein diet or should you cut out carbohydrates instead? Maybe you should add veggies and other healthy options?
Weight loss researchers, like all good scientists, prefer to address these questions individually. But Drew Sayer, Ph.D., wants answers faster.
“I’m moving my research into a more pragmatic space,” said Sayer, an assistant professor at the University of Alabama in the Birmingham Department of Nutrition Sciences.
Sayer is a pioneer in the field of SMART weight loss research studies. Sequential randomized trials with multiple assignments “bridge the translational gap between traditional clinical research and research in implementation,” said Sayer. “If you go to obesity counseling and don’t get better after four to six weeks, your dietitian would say, ‘Let’s try something different.’ That’s not what happens in a typical research study. You would be randomized to Intervention A or Intervention B and stick with it all the time. A SMART design builds up at a predetermined point in time when we identify participants as responders or non-responders. The responders continue and the non-responders are assigned to a second set of interventions. ”
No one size fits all
In other words, SMART studies are designed to address the fact that one size fits all just doesn’t work when it comes to weight loss.
As an example, consider one of Sayer’s recent studies that he and his team call SMART Lifestyle.
“When you meet a friend and they say, ‘I’m on a diet,’ they usually mean several things,” said Sayer. “They’re trying to lose weight, improve the quality of their diet, and do more exercise at the same time. But in reality, these are three different interventions: reducing calories, improving your diet, and getting more exercise. This study tries to pull them apart. ”
The participants are initially randomly assigned to nutritional counseling or exercise counseling, without weight loss being the main focus.
“Then after eight weeks we assess their glucose tolerance, a measure of their metabolic health,” said Sayer. “If they don’t get better, we will do one of two things: prescribe weight loss or give them metformin to control their glucose.”
“When you meet a friend and they say, ‘I’m on a diet,’ they usually mean several things,” said Sayer. “They’re trying to lose weight, improve the quality of their diet, and do more exercise at the same time. But in reality, these are three different interventions: reducing calories, improving your diet, and getting more exercise. This study tries to pull them apart. “
Sayer is very enthusiastic about SMART Lifestyle.
“It tries to untangle all of these separate components,” he said. “You talk to people who have lost weight and say, ‘When I exercise, the weight drops.’ Other people say, ‘When I exercise, I get so hungry that I eat twice as much.’ People identify themselves as responders or non-responders to exercise, but we don’t have a diagnostic test that can. The SMART design enables this type of test. We are trying to collect a comprehensive set of basic variables in order to begin creating profiles that will enable us to prescribe precise diet and precision exercise recommendations to a person. “
These baseline variables are relatively simple measurements that can be obtained from blood samples and other quick, inexpensive tests.
“If it’s not a test that we can easily do in a clinical setting right now, I’m not really interested,” said Sayer. “Most of my research takes place in the Family Medicine Clinic at UAB Hospital Highlands. So when we see something that works, the next step is to offer it as part of our clinical program. “
Upon completion of the studies, researchers using SMART designs perform statistical modeling that “tries to retrospectively map people to the intervention they should have been assigned to,” Sayer said. “So if we see someone with similar traits in the future, we can hopefully assign them to the intervention that will benefit them most.”
Lose weight – without losing muscle mass
In another study, funded by an NIH K01 award for promising young researchers, Sayer explores ways to combat sarcopenic obesity, a condition involving too much fat combined with too little skeletal muscle.
“We want to know in people 50 and over whether we can achieve weight loss while maintaining lean mass, a large part of which is made up of skeletal muscles,” said Sayer.
“When people lose weight, they don’t just lose fat,” said Sayer. “Anywhere between 25 and 30 percent of what they lose is skeletal muscles. If you are 35 or 40 years old, are obese, and are losing a significant amount of body weight, the small amount of skeletal muscle that you lose is not a problem. But if you have sarcopenic obesity – low muscle mass with obesity, which is very common in people over 60 – you really need to think about the pros and cons of losing weight in this group. If you lose weight and lose too much skeletal muscle, you may have functional impairments. “
“In the PRESS ON or Protein and Resistance Exercise to Stop Sarcopenic Obesity Now study, we are looking at the two most common strategies to achieve this – high-protein diets and weight training,” said Sayer. Previous studies and clinical experience have shown different responses.
“Some people respond well to resistance training and others to dieting, but there is no test to find out what is which,” Sayer said.
His study begins with participants being randomly assigned to either a high-protein diet or resistance training. Both groups start out as counseling-based interventions, says Sayer. They do that for eight weeks; Then if they lose a certain amount of fat mass and do not lose too much lean mass, they will be classified as responders and will stick with the intervention.
If they’re non-responders, they can be randomized to step them up: if they’re in a high-protein group to start with, they’re given whey protein supplements on a daily basis. If they are in the strength training group, they will be assigned a personal trainer two days a week. The other intervention is to combine and perform both protein supplements and weight training.
“We only choose strategies that have been shown to be effective in advance,” said Sayer. “We know that resistance training works, but at what level and for whom? We start with counseling interventions that are the easiest and cheapest to scale. We reserve supplement strategies and personal training for those who do not respond. ”
“How To Actually Treat Obesity”
Sayer is currently starting a third SMART study at the Family Medicine Clinic in people with prediabetes.
“A common weight loss strategy for this group is to cut down on carbohydrate intake,” said Sayer. “The first interventions will be either low-carb or low-fat – not low-ketogenic, but moderately reduced.” After four weeks, those who have lost enough weight will continue, while the non-responders will “receive supervised exercise or an early, temporary one.” Follow diet, “said Sayer. (The latter refers to eating all meals within a certain time frame each day, e.g. from 8 a.m. to 2 p.m.)
“The idea behind all of these studies is to develop the most effective interventions,” said Sayer. “The term we use is ‘Intervention EASE’: the most effective intervention we can create within the key limits of affordability, scalability and efficiency. We want to break these complex, multi-component interventions into their component parts and keep only the parts that are useful, ”he said. “And for the useful: Find out the intensity you need to provide at the most cost-effective level.”
It is important to note that the participants in Sayer’s studies are dealing with all of the related disorders that occur in people with obesity.
“I’ve read so much research that has done research on people who are obese but who are otherwise healthy,” said Sayer. “You read in the introductions to these papers that obesity is linked to all of these chronic diseases and metabolic disorders, but then you go on and study people who don’t have any of these conditions. It’s one of my biggest annoyances in obesity clinical research because it excludes the people who would benefit most from weight loss. “
“We are specifically recruiting people with weight-related complications – high blood pressure, high cholesterol, prediabetes,” said Sayer. “I want to study the people I want to intervene with. You would like to inform your future clinical practice. A clinical practice will not refuse anyone to participate in a clinical program because they have diabetes. That is exactly what you want in these programs. But in order to answer scientific questions, we often exclude people. “
Sayer began his pre-doctoral training by measuring brain responses during strictly controlled feeding studies to see if the brain’s response to images of different foods was a predictor of subsequent food intake.
“It was interesting; but at the end of the day it doesn’t tell us much about how to actually treat obesity,” he said. During the last year and a half of his PhD, Sayer was on a translational fellowship at the Indiana Clinical and Translational Sciences Institute – the equivalent to the Center for Clinical and Translational Science of the UAB.
“That’s when I was introduced to this concept of translational science – how to do research that can lead to more actionable points about treating obesity,” he said. He was a postdoctoral fellow with James Hill, Ph.D., who is now Chairman of the Department of Nutrition Sciences at UAB and Director of the University’s Nutrition Obesity Research Center. After Hill came to Birmingham, he recruited Sayer.
“For me, the key theme of a SMART design is bridging this translational gap between clinical research and implementation science,” said Sayer. “A lot of good research dies at this stage and doesn’t make it to a clinic. That’s what we’re trying to do; say, ‘If that works, now what?’ We have to work actively to move from one level to the next. “
To learn more about Sayer’s studies and inclusion criteria, call 205-975-4113 or email firstname.lastname@example.org.