You’ve probably heard of Ozempic and Wegovy, two popular medicines used for weight loss. But what about semaglutide, the active ingredient in each?
Semaglutide is what makes the medicines work. And it’s very effective: some people lose around 15% of their starting weight after using it for just over a year.
That’s not all that semaglutide can help with, though. Scientific research shows that it has a bunch of potential health benefits: it’s used to treat type 2 diabetes, can improve heart health, and may even have benefits for your brain. We’ve explained it all for you below.
What is semaglutide and how does it work?
But first, the basics: semaglutide is a type of medicine called a GLP-1 agonist. That means that it works by copying how the natural hormone GLP-1 behaves.
GLP-1 is released naturally when we eat and has a range of different effects.
For one, it makes you feel full. GLP-1 tells the pancreas to produce insulin in response to you eating, which signals to the brain that you’ve had enough. It can also slow the rate at which food moves through your digestive system, prolonging your feeling of fullness—and talk directly to your brain to tell it to dial down your appetite.
By stimulating insulin production, semaglutide also keeps your blood sugar in check. Insulin’s job is to shuttle the sugar in your blood around your body so it can be used as energy. So, if more insulin is released, less sugar is left to hang around in the blood. This last part is important for weight loss because your body can store the excess sugar as fat.
The liver is part of this picture, too: one of its jobs is to produce glucose that’s used as energy. Semaglutide can talk to the liver and tell it to make less sugar.
Plus, some people using semaglutide have said that it quietens their “food noise”—constant and intrusive thoughts about food. For example, thinking about food all the time or checking food delivery apps multiple times per day.
Benefits of semaglutide for weight loss
This is what semaglutide is best known for. But before we look at what it can do, let us quickly explain the difference between Wegovy and Ozempic.
Wegovy is licensed as a weight loss treatment and is available in higher strengths of semaglutide. On the other hand, Ozempic is licensed for type 2 diabetes and comes in lower doses, but is often used off-label for weight.
FYI: scientific research on the benefits of semaglutide for weight loss tends to look at doses you’d get on Wegovy.
Okay, so what does the research say? Glad you asked. A programme called the STEP trials explored how safe and effective semaglutide is when used to support weight loss. Here, we’re only going to look at results from people without type 2 diabetes.
Findings were pretty similar across different trials. After taking semaglutide for 68 weeks, STEP 1 showed an average loss of 14.9% body weight while in STEP 3, it was 16%. At 104 weeks, STEP 5 showed a mean loss of 15.2%.
In all of this research, semaglutide was taken alongside a balanced, calorie-reduced diet and regular exercise coupled with therapy to develop behavioural changes. For example, in STEP 3, participants were on a low-calorie diet (1,000-1,200 calories per day) for the first eight weeks, and then ate 1,200-1,800 calories per day for the rest of their time using semaglutide. In STEP 1, people ate 500 calories less than what they’d normally burn each day.
We’ve covered what you might expect week on week when you start taking Wegovy. Just remember, semgalutide is meant to supplement lifestyle changes. If you take it on its own, it might not work as well.
Other benefits of semaglutide
Type 2 diabetes
Did you know that this was actually the first approved use for semaglutide? Yep—Ozempic was developed to treat type 2 diabetes and hit the market back in 2017.
People with type 2 diabetes either don’t produce enough insulin or their body doesn’t react well enough to insulin’s effects (this is called insulin resistance). As a result, their blood sugar is too high.
Like we mentioned earlier, semaglutide helps keep blood sugar under control by stimulating insulin production and telling the liver to produce less glucose.
And because it can help with weight loss, semaglutide can improve our sensitivity to insulin. Weight gain affects the body in different ways, and some of these effects—like increased inflammation—can bring on insulin resistance.
Heart disease
Managing your weight is good for your heart, too. Getting to a healthy weight can improve blood pressure and cholesterol, while lowering levels of fat in the blood—all of which have cardiovascular benefits.
Semaglutide has been shown to lower blood pressure and the risk of heart attack and stroke in people with type 2 diabetes.
In a trial called SELECT, people taking semaglutide were 20% less likely to experience a stroke, heart attack, or further heart issues. The research looked at over 17,000 people without diabetes, but who had preexisting heart conditions and a BMI of 27 or more.
Polycystic ovary syndrome (PCOS)
Polycystic ovary syndrome (PCOS) is a condition where people assigned female at birth have too many “male” hormones (called androgens). It can lead to weight gain via two routes: insulin resistance and excess androgens causing fat to form around the middle.
This creates a vicious circle: as weight goes up, insulin resistance gets worse (we explained why earlier—weight gain can make us less sensitive to insulin). And because this means that more sugar is left to hang around in the blood, this can then bring on further gains.
But that’s not all. As insulin resistance increases, the body produces even more insulin to compensate—which in turn causes androgens to rise. Not only does this contribute to weight gain, but high androgen levels can aggravate PCOS symptoms like acne and hair loss.
So, if semaglutide can help with weight loss, then it could improve insulin resistance and lower androgen levels.
There’s some research looking into this. In one study, 27 people with PCOS and a BMI of 30 or more took semaglutide for six months and saw a mean loss of 11.5kg. And in 80% of participants who were responsive to the treatment, their menstrual cycles became regular again. In fact, losing just 5% body weight has been shown to reduce PCOS symptoms.
Addiction
Earlier on, we mentioned how people taking semaglutide said they had less “food noise”, a kind of obsessive preoccupation with food. This isn’t an addiction per se, but semaglutide’s impact here suggests that it might be helpful in managing addictive behaviours.
People have noted that they’ve drank less alcohol and cut back on smoking since taking semaglutide. Some even put a stop to their compulsive shopping habits. This indicates that semaglutide influences brain activity around the perception of reward.
For example, having an alcoholic drink usually causes dopamine levels to rise. But one study in rats found that semaglutide diminished this effect: alcohol gave the rats less of a dopamine hit and they ended up drinking less overall. Off the back of these results, researchers are considering whether semaglutide could treat alcohol use disorder.
Alzheimer’s
We know that semaglutide works by copying the effects of the hormone GLP-1. And GLP-1 does a lot! As well as the effects we’ve already mentioned, it can interact with certain types of cells that could potentially slow the progression of Alzheimer’s disease.
When we become resistant to insulin, we become less responsive to the messages that insulin sends to the brain. This can reduce the brain’s ability to get the energy it needs and function efficiently—which could lead to impaired cognitive function. In some people, this eventually develops into dementia.
By acting like GLP-1, semaglutide can reactivate some of these pathways and help protect the brain.
Semaglutide is currently being studied as a potential treatment for early Alzheimer's. It’ll be a few years before we see the results from that research, though.
Semaglutide side effects: what to know
It’s pretty common to experience side effects while using semaglutide. But usually, these are mild and will clear up on their own. But if they stick around or are bothering you, check in with your clinician.
Mostly, side effects affect the gut, including nausea, diarrhoea, vomiting, and constipation. These symptoms might affect over one in ten people.
You shouldn't use it if you're pregnant or breastfeeding, or have any allergies to the ingredients in Wegovy. Disclose all of your health conditions and current medications to your prescriber, so they can appropriately assess whether the treatment is safe for you.
Is semaglutide right for you?
We’ve been talking about the benefits of taking semaglutide, but we also want to remind you that it’s in no way a shortcut to reaching your goals.
When used for weight loss, semaglutide is supposed to be taken for at least a year, alongside lasting changes to your diet and exercise schedule. We know that might sound like a long time, but trust us, your consistency and patience will pay off! If you stick with them, your new habits will start to feel normal in no time.
And, like any medicine, semaglutide isn’t suitable for everyone. It’s recommended for people with a BMI of 30 or more, or who have a BMI of 27-30 plus at least one other condition related to their weight.
If you aren’t sure, you can speak to your prescriber about whether you might benefit from semaglutide.
Your journey with semaglutide
We know that losing weight can be tough—but so are you. We know that you can reach your health goals and we’re here to support you all the way.
As part of our weight loss programme, you can get access to our team of expert coaches who will help you create a personalised plan of action. They’ll be your advisors and cheerleaders, and together you can track your progress on our app. Plus, you’ll get your medication posted to you each month.
You can find out if you’re eligible to join by filling out this speedy form.
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