GLP-1 RAs effectiveness for weight loss
Key Takeaways
GLP-1 RAs work by mimicking a natural hormone in the body.
Some GLP-1 RAs are approved for weight loss, while others are approved for treating diabetes.
Overall, GLP-1 RAs have been found to lead to weight loss of between 5 and 15% of starting body weight, though there are differences in the effectiveness of different specific medications in this class.
Many people hit a weight loss plateau before reaching their goal weight.
A weight loss plateau occurs because the body’s use of calories is reduced as the weight loss journey progresses.
Resistance training, adjusting caloric intake, and increasing overall physical activity can all help a person to break through a weight loss plateau.
There’s been a lot of interest recently in GLP-1 receptor agonists, or GLP-1 RAs. Some medications in this class are used to treat diabetes, while others are used to promote weight loss in people who are significantly overweight.
Those who are interested in using GLP-1 RAs for weight loss often wonder how effective these medications are. How much weight can a person expect to lose on GLP-1 RAs? Can you do anything to support the effectiveness of the medication?
How do GLP-1 RAs work?
All GLP-1 RAs work in the same basic way. They mimic a natural hormone known as glucagon-like peptide-1, or GLP-1. This hormone is normally produced after meals. GLP-1 RAs have a few different effects in the body:
They increase insulin, which is a hormone that lowers blood sugar.
They decrease glucagon, which is a hormone that causes increased fasting blood sugar.
They slow down emptying of the stomach after eating, causing you to feel full for longer.
They act in the brain to reduce appetite and food cravings.
All of these actions help people to consume fewer calories without battling extreme hunger and cravings. They also help to keep blood sugar under control.
How much weight can you expect to lose on GLP-1 RAs?
Although all GLP-1 RAs work in the same basic way, they’re not all specifically approved for weight loss. Instead, some are approved for treating diabetes. People who take GLP-1 RAs often lose weight, even if this is not the primary purpose of the medication. However, certain characteristics of the medication, such as the dosage, are different when it’s being used for weight loss than when it’s being used for treating diabetes.
There are currently two GLP-1 RAs that are approved in Singapore for weight loss. These include Saxenda, which is a form of liraglutide that’s given as a daily injection, and Wegovy, which is a form of semaglutide that’s given as a weekly injection. Zepbound, which is a form of tirzepatide that’s approved in the US for weight loss, is not yet approved in Singapore.
GLP-1 RAs have been shown in multiple clinical trials to be effective for weight loss, which is why they have been approved for this specific purpose. Studies of semaglutide have shown that it leads to an average weight loss of about 15% of starting body weight (meaning the body weight before taking the medication). Liraglutide has been found to cause an average weight loss of 5 to 10% of starting body weight.
Some recent studies have found that tirzepatide results in weight loss of more than 26% of starting body weight. However, tirzepatide is not currently approved for weight loss in Singapore. It’s only approved for treating diabetes.
Why do people reach a weight loss plateau?
When a person first begins a weight loss journey – whether this includes GLP-1 RAs or not – It’s common to lose weight relatively quickly at first. However, over time, weight loss generally slows down. Eventually, a person will reach a weight loss plateau. It can feel frustrating for many people when they stop losing weight, even though they’re still maintaining the healthy habits that initially led to successful weight loss.
A weight loss plateau occurs because of:
Reduced energy expenditure. When you’re eating fewer calories than your body is using, your body will try to conserve energy and reduce its use of calories. This is sometimes known as “having a slower metabolism.”
Loss of muscle tissue. When you lose weight, you don’t lose only fat tissue, but muscle tissue as well. In fact, studies have found that between 20 and 50% of the weight that people lose while on a GLP-1 RA is muscle mass. Muscle tissue uses a lot of energy, even at rest. With less muscle tissue, your body uses fewer calories overall.
Because of these factors, your body uses fewer and fewer calories as you progress through your weight loss journey. If you keep your caloric intake and your physical activity the same, then you’ll eventually reach a point where your calories in and calories out are balanced, even though your caloric intake is lower than it was before you started your weight loss journey.
At this point, you’ll reach a weight loss plateau. Maintaining the same habits will allow you to maintain your weight loss, but won’t allow you to lose any more weight.
Getting over a weight loss plateau
If your weight loss plateau occurs when you’re at your goal weight, then all you have to do is maintain your new healthy habits, and you’ll be able to maintain your weight loss for the long term. Some people are lucky enough to reach their plateau when they’re already at their goal weight.
However, it’s common for people to hit a weight loss plateau before reaching their goal weight. If this happens to you, then you’ll want to find a way to get over the weight loss plateau, so that you can continue to lose weight and achieve your goal.
Getting over a weight loss plateau generally involves some combination of the following factors:
Resistance training. These are exercises designed to build muscle tissue, such as weight training, using resistance bands, or doing bodyweight exercises. Because muscle tissue uses a lot of energy even at rest, having more muscle tissue increases your body’s use of calories. Resistance training has been found to be effective at preventing the loss of muscle tissue during weight loss.
Adjusting caloric intake. When you first started your weight loss journey, you may have calculated how many calories you needed to eat in order to achieve a caloric deficit of about 500 calories. As your weight loss journey progresses, your body is using fewer calories, so the same caloric intake no longer results in a 500-calorie deficit. Try recalculating your caloric needs based on your new body weight while you’re in your plateau. You will likely need to adjust your caloric intake downward a bit more in order to continue losing weight.
Increasing physical activity. The more active you are, the more calories you’ll use to fuel that activity. Increasing your level of physical activity may help you to break through a weight loss plateau. This can involve not just resistance training, but also aerobic activity (such as walking, running, cycling, dancing, or swimming). Don’t go overboard – too much physical activity can cause injury to the body, so if you’re already quite active, then increasing it may not make sense. However, if your physical activity is currently moderate, then you could increase it a bit to break through a weight loss plateau.
Why a holistic approach works for a healthy weight loss journey
In order to achieve a healthy body weight, it’s important to take a holistic approach. Successful weight loss always involves paying attention to both diet and exercise. Some people also benefit from taking GLP-1 RAs. These medications can make it easier to reduce your caloric intake. However, the medications aren’t a substitute for a healthy lifestyle, but rather an addition.
It can be helpful to have support in order to achieve successful weight loss. A health coach can help you to design – and stick to – a healthy lifestyle plan. If you hit a weight loss plateau, they can help you find ways to break through it. If you’d like to consider using GLP-1 RAs to help you on your weight loss journey, then you’ll need to see a physician for this, because GLP-1 RAs are prescription medications.
Our NOVI Optimum Plus clients always receive support from both physicians and health coaches. This maximizes the chances of successfully achieving a healthy body weight, which leads to more energy and better health overall.
NOVI Optimum Plus includes:
Doctor consultation (video or in-clinic)
GLP1-RA Medication with free delivery
Digital coaching & support