Trying to lose weight can be a disheartening process. You might be doing everything right—eating well, exercising, and living a healthy lifestyle—only to find that the scale is barely budging.
Frustrating though that can be, it may help to remember you aren’t the only one in this position. Many people, fed up with conventional methods, have been turning their attention towards weight loss medications.
You have no doubt heard about injectable medications like Mounjaro, Wegovy and Saxenda (otherwise known as GLP-1 receptor agonists). When taken over a prolonged time period, they help some people lose between 10 to 20% of their initial body weight on average in under two years.
But perhaps you don’t like needles. You might be wondering whether there are any tablets or supplements that might support your weight loss journey, or how weight loss pills compare to injections. Here’s what you should know if you’re considering going down that route.
What you should know about weight loss pills?
A big caveat to begin with—no pill should be treated as a substitute for diet and exercise. Weight loss drugs are always recommended as part of a comprehensive weight management plan, which includes all the standard lifestyle advice you’re probably following already. On top of any medication, you should also eat a balanced diet, stay active, minimise stress and get enough sleep where you can.
With that disclaimer out of the way, we can confirm that there are lots of different diet pills on the market. In fact, it’s a bit like the Wild West out there. You’ve probably encountered quite a few ‘slimming pills’ or ‘appetite suppressants’ if you’ve ventured onto social media.
We’d advise approaching with caution. Only a few of these tablets have been clinically tested, meaning we can say for sure that they work. And there’s only one option the NHS recommends. That’s orlistat.
Weight loss pills to know
Orlistat
Orlistat is a prescription-only drug that interferes with the way your body absorbs fat. It’s a licensed medication, which is available to some people on the NHS and to others through private prescription. You take a 120mg pill up to three times a day, immediately before, during or within one hour of consuming a fat-containing meal.
It doesn’t work for everyone—if, after 12 weeks you haven’t lost 5% of your body weight, orlistat probably isn’t the right choice for you. But for others, it can be very effective. In a clinical trial, 60% of orlistat patients met that 12-week benchmark. Most of this group (62%) went on to lose more than 10% of their starting weight within a year. In another study, patients taking orlistat lost an average of 5.6% of their body weight within 24 weeks.
Glucomannan
Another option is glucomannan, a type of fibre derived from the elephant yam plant. Glucomannan is a dietary supplement, rather than a medication, which means it’s not available through the NHS and hasn’t been tested as rigorously as orlistat. But some small studies have found slight benefits for weight loss, at least when combined with a calorie-controlled diet.
Rybelsus
There's also Rybelsus, which is essentially the pill version of Ozempic or Wegovy, as it contains the active ingredient semaglutide. In one study, the average weight loss in people taking 14mg Rybelsus was 5% after 26 weeks compared to placebo. Right now though, Rybelsus is only licensed for type 2 diabetes, though that may change in future.
Amycretin
A newer oral medication called Amycretin is also in development. It mimics both GLP-1 and amylin hormones, and early trials suggest it could be even more effective than Wegovy. However, it’s still in the clinical trial phase and not yet available on prescription.
Orforglipron
Orforglipron is a new GLP-1 tablet in development by Eli Lilly—the same company behind Mounjaro. Unlike injectable GLP-1 medications like Wegovy and Saxenda, orforglipron is a once-daily oral tablet that mimics the hunger-suppressing hormone GLP-1 to help reduce appetite. Though like Rybelsus and Amycretin, it’s not yet available in the UK.
How do weight loss pills work?
Orlistat works by blocking fat absorption in the digestive system. Once you’ve taken a dose, it travels to the gut, where it stops a chemical called lipase from working properly. (Lipase normally helps the body break down fat, allowing the digested fat to be stored or used for energy.) After you’ve taken this weight loss pill, your body absorbs around 30% less fat than normal, with the rest being passed out when you go to the toilet. That equates to around a 200-calorie deficit.
Glucomannan is a type of soluble dietary fibre, which has been reliably associated with slight weight loss. When we consume soluble fibre, it absorbs water in our body, forming a gel-like consistency. This might help suppress your appetite. It might also change the composition of the microbiome (gut bacteria), which can have additional health benefits.
Risks and benefits of weight loss pills
Weight loss pills aren’t a quick fix. And they certainly aren’t a substitute for a healthy diet or exercise. Any claim to the contrary should be taken as too good to be true.
It’s also important to be aware of side effects. Orlistat can have some minor side effects including:
- Oily poo
- Needing the toilet urgently or more frequently
- An oily discharge from your back passage
- Farting (flatulence)
That’s because undigested fats are passed out when you go to the toilet. (Don’t worry too much though—you can minimise these issues by eating a low-fat diet.)
If you’re interested in taking these kinds of medications or supplements, it’s important to speak to a healthcare provider first. They can help you determine which choices might be most appropriate for you.
Side effects support at Voy
"If you're using Voy and you experience any side effects, rest assured that our expert clinicians are just a message or phone call away. They can adjust your dose, prescribe medication to ease your symptoms, or simply offer reassurance.
Everyone responds differently to weight loss treatment and we'll help you find what feels right for you."
Your weight management journey
The internet is full of weight loss pills, with bold promises attached! Recently, weight loss patches (sometimes called GLP-1 patches, although they don't actually contain any GLP-1 medicines!) have emerged too. However, the vast majority haven’t been well-studied—and some might even be dangerous. For safe and sustainable weight loss, there’s only really one pill that has demonstrated its worth, and that’s orlistat.
Remember that there are other options too. Voy provides a full spectrum of weight loss offerings, including GLP-1 injections. Just like weight loss pills, these aren’t for everyone. But they can be extremely effective.
Our team will advise on the best option. Why not take a few minutes to fill out this short form to see if you’re eligible?
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