Appetite suppressants do what it says on the tin: they make you feel full, so you eat less. That’s how the popular weight loss injections Saxenda, Wegovy, and Mounjaro all work.
There’s loads of interest in those medicines right now, but appetite suppression is a well-known strategy for weight loss. Some people use prescription tablets or supplements to help them feel full, for instance.
If you’re wondering whether to try an appetite suppressant, you probably have a bunch of questions, like: how do they work, and which one is right for me? Read on—we’ve laid it all out for you below.
Types of appetite suppressants
Let’s take a look at the main appetite suppressants you can get in the UK.
Weight loss injections
There are three options here: Saxenda, Wegovy, and Mounjaro weight loss injections.
While they all work in broadly the same way (we’ve covered this in more detail below), they are separate medicines: they each have a different active ingredient, come in different doses, and may bring on their own side effects. Your provider can advise on which is best for you personally.
Tablets
You’ll need a private prescription for appetite suppressant pills.
But there’s only one tablet for weight loss available on the NHS i.e. orlistat and it works by reducing the amount of fat your gut absorbs from food rather than making you feel full.
OTC appetite suppressant pills
And then we have over-the-counter options, which are mostly different types of supplements. Often, these will contain fibre, which can help slow your rate of digestion (this makes you feel fuller for longer).
But be careful here: supplements don’t have to go through the same level of safety testing as medicines and some products make big promises that aren’t always backed up by science. It’s a good idea to check in with your provider if you’re not sure.
Natural appetite suppressants
What about natural appetite suppressants? There are some supplements and strategies that might help.
Glucomannan
Glucomannan is a dietary fibre that dissolves in water. It comes from the root of the konjac plant.
When you take glucomannan, it forms a thick gel in your stomach. Not only does said gel sit in your gut for longer, but it can absorb water while it’s in there and expand. Both of these factors can make you feel full.
Caffeine
Could your morning cup of coffee help stave off your appetite? It’s often said that caffeine is an appetite suppressant, as well as a short-term stimulant for your metabolism. But the scientific evidence around its role in weight loss isn’t decisive: some studies suggest that it might help with weight loss , though the effects may be modest.
Drinking too much coffee (or tea) isn’t recommended though. Up to 400mg of caffeine a day appears to be safe for most healthy adults.
Filling foods
Some foods will keep you feeling fuller for longer than others, even while being lower in calories. Lean sources of protein (chicken, tofu, fish) are one example, along with foods that are high in fibre (fruits and vegetables, whole grain foods like brown rice).
We’re big fans of these foods here at Voy: they’re super important aspects of a healthy, balanced diet that supports weight loss. The recommended daily fibre intake for adults is 30g a day.
How do appetite suppressants work?
Weight loss injections make you feel full by acting like your body’s natural hunger-suppressing hormones. Namely, they slow down the rate of digestion while reducing your appetite and cravings.
Both Saxenda and Wegovy copy a hormone called GLP-1, while Mounjaro acts like both GLP-1 and GIP (this dual action makes Mounjaro the more potent medicine). You might hear people referring to these medicines as peptides , because it’s a way to describe their active ingredients: liraglutide, semaglutide, and tirzepatide, respectively.
Natural options work in various ways, so do check the label and ask your provider if you aren’t sure.
Are appetite suppressants actually effective?
We’re glad you asked.
There’s solid clinical research around weight loss injections when they’re used alongside a balanced, nutritious diet and regular exercise. After taking them for at least a year, studies show that:
- People on Saxenda lost an average of 7.4% of their starting weight.
- For those using Wegovy weight loss injections , that figure is 14.9%.
- People on Mounjaro lost 25.3%.
When it comes to weight loss supplements, the scientific evidence is a bit of a mixed bag. For example, there’s some studies showing modest success on glucomannan , while others indicate that it has no notable effect on weight.
Are appetite suppressants safe?
Weight loss injections are generally considered safe for most people, though you shouldn’t take them if you’re pregnant or breastfeeding.
But they do come with side effects. The most common symptoms include:
- Nausea
- Vomiting
- Diarrhoea
- Constipation
- Stomach pain (Mounjaro & Wegovy)
- Headache (Saxenda & Wegovy)
Check in with your provider about other appetite suppressants. They’ll consider your current health and medical history when deciding whether they’re right for you.
Your next step
Okay, but which is the best appetite suppressant for you personally? That’s something for you and your provider to decide. But if you’ve tried to lose weight another way and it didn’t work out as you hoped, weight loss medication could be a great option.
Though these medicines are only part of the picture: building healthy habits that last is key to reaching your goals and maintaining your progress.
Our team of expert coaches can help with that. Through our weight loss programme, they’ll work with you to create a new, personalised routine—and be there to cheer you on at every step. You’ll also get weight loss medication posted to you each month.
Find out if you’re eligible by filling out this short form. Our clinicians will review it and come back to you soon.
FAQs
Can natural supplements effectively suppress appetite?
They may have some effect on appetite. Though the evidence here is patchy: some supplements might have a modest effect while others might have none at all. On the other hand, weight loss medicines are backed by solid evidence.
What lifestyle changes can complement the use of appetite suppressants?
We love this question! A healthy lifestyle is a crucial part of any weight loss programme. In fact, if you just take weight loss medicines on their own, they might not work as well. The basic advice is this: eat a balanced, nutritious diet with fewer calories than you burn each day, and do two strength sessions plus 150 minutes of moderate-intensive exercise per week.
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