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Weight Loss Jabs UK

Mike Gibbs
Written by

Mike Gibbs

Medically reviewed by

Fiona Moncrieff

6 min read
Last updated April 2024

Jump to: What’s the best weight-loss jab? | How do GLP-1 weight-loss jabs work? | Are there any new weight-loss jabs being released? | How much do weight-loss jabs cost? | How do I buy weight-loss jabs? | Why should I buy weight-loss jabs from Second Nature?

As of August 2023, there are two weight-loss jabs currently available in the UK:

  • Semaglutide: more commonly known by their brand names, Ozempic and Wegovy
  • Liraglutide: more commonly known as Saxenda

Both of these weight-loss jabs are what they say on the tin: you have to inject them into your body.

In terms of injecting yourself, the main difference between semaglutide (Ozempic/Wegovy) and liraglutide (Saxenda) is that with liraglutide, you have to jab yourself every day. With semaglutide you only have to jab yourself once per week.

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What’s the best weight-loss jab?

When comparing semaglutide and liraglutide to establish which is the ‘best’ weight-loss jab, you’d probably want to use two criteria:

  1. Which weight-loss jab leads to the highest weight loss?
  2. Which weight-loss jab has the fewest reported side effects?

For both of these criteria, semaglutide performs better than liraglutide.

In most reported trials, semaglutide has shown better rates of weight loss than liraglutide. For example, a randomised controlled trial was run in 2022 which directly compared liraglutide and semaglutide.

The results showed that semaglutide had almost twice the weight-loss results as liraglutide: 15.8% weight loss for semaglutide vs 6.4% for liraglutide.

The same trial also reported that semaglutide had fewer reported side effects than liraglutide.

On average, roughly 1 in 8 people reported side effects when taking semaglutide, with almost twice as many people reporting side effects when taking liraglutide (approximately 1 in 4 people).

So with the above in mind, we’d say that the current best weight-loss jab is semaglutide.

If you’d like to read more about the differences between liraglutide and semaglutide, we’ve got a much more detailed guide here: Saxenda vs Ozempic

How do GLP-1 weight-loss jabs work?

To explain in the most simple manner, both semaglutide and liraglutide mimic a hormone in the body called GLP-1.

Under normal circumstances, GLP-1 is released by your small intestine when food passes to it from the stomach. The GLP-1 hormone travels back to the stomach and tells the stomach to reduce the flow of food to the small intestine.

Why? To avoid all the food from your stomach moving to the small intestine in one go, potentially leading to blood sugar spikes and generally too much food in the small intestine at once.

The natural GLP-1 in your body only lasts for a few minutes before being broken down. When this happens, the stomach is free to then release more food into the small intestine.

In short, the GLP-1 hormone controls the rate of food movement from your stomach to your small intestine. GLP-1 does also have some satiety-managing effects on your brain as well as modulating the release of the insulin and glucagon hormones in your body.

As a side note, higher levels of insulin reduce the levels of blood sugar in your blood. Glucagon has the opposite effect, so higher levels of glucagon increase the levels of blood sugar.

So if you want to maximise the reduction in blood sugar levels you’d want to simultaneously increase insulin levels and also lower glucagon levels, which is exactly what the GLP-1 hormone also does.

Getting back on track: weight-loss jabs like semaglutide and liraglutide mimic the natural GLP-1 hormone, so they also slow the rate of food moving from the stomach to the small intestine.

The key difference is that the GLP-1 drugs last for much longer in the body than the natural GLP-1 hormone. Instead of lasting for a matter of minutes, the drugs in weight-loss jabs last for hours/days.

All-in-all, this leads to you feeling less hungry because you have food in your stomach for longer.

This also explains why a small proportion of people have GI side effects for the first few weeks of taking semaglutide and liraglutide, as their bodies get used to the new slower rate of digestion and food passing from the stomach to the small intestine.

The biology of GLP-1s is quite interesting when you understand it a little more.

Are there any new weight-loss jabs being released?

Yes. There is a new weight-loss jab coming from the drug manufacturer, Eli Lilly, called tirzepatide. This is expected to be released in 2023 or 2024 under the brand name ‘Mounjaro’.

Studies to date have shown promising results for tirzepatide, with weight-loss results potentially higher than the current best weight-loss jab: semaglutide.

The second brand of semaglutide, called Wegovy, is also expected to be released in 2023 in the UK.

Whilst Wegovy is the same drug as Ozempic (i.e. both are semaglutide), the Wegovy brand is expected to be officially licensed to be provided to people living with obesity.

In contrast, the Ozempic brand is mainly targeted for those people living with type 2 diabetes.

How much do weight-loss jabs cost?

Weight-loss jabs are not cheap. For a monthly prescription of semaglutide, you can probably expect to pay at least £299 per month in 2023.

These prices may come down in 2024 as more semaglutide manufacturing plants are produced, but at the moment everything is in very short supply due to the weight-loss jab’s popularity.

We’d generally always recommend trying Second Nature’s weight-loss programme first before considering a weight-loss jab. Changing your habits is the most sustainable way to achieve long-term weight loss, and it’s also less expensive.

How do I buy weight-loss jabs?

You can buy weight-loss jabs from online pharmacies and providers, like Second Nature. Other providers in the UK include companies like Boots, Superdrug, Manual, Numan, myBMI, and Juniper.

You’ll typically have to take an online quiz to understand if you’re eligible. Please don’t lie about your details on these quizzes, as if it’s found out that you’re a lower BMI than the eligibility criteria, then the pharmacists will likely stop your prescription after one month.

Most reputable online pharmacies will double-check your details with your NHS records.

Why should I buy weight-loss jabs from Second Nature?

If you’ve decided that you would like to try a weight-loss jab, and you also meet the eligibility criteria, then you might ask yourself the question: why choose Second Nature over other providers?

Our answer would be: for peace of mind

Second Nature is the only UK company that provides private weight-loss injections and is also trusted by the NHS to provide weight-loss services.

The NHS has used Second Nature for over 6 years, and we ensure we abide by the highest levels of data security and patient safety.

With that, we believe there comes a level of authenticity and peace of mind that other providers cannot match (e.g. Boots, Superdrug, Juniper, Numan, Manual, etc).

If you want to go with a company that has a proven track record of providing the most effective digital weight-loss programme to the NHS (as proven in our official scientific publications in the British Medical Journal, and others), then give us a go.

Wegovy information

Product name Wegovy
Active ingredient Semaglutide
Manufacturer Novo Nordisk
Price £229
What’s included?
    • Access to a registered nutritionist or dietitian five days a week via our award-winning app
    • Weighing scales and our hardback recipe book
    • Peace of mind that we’re the only Wegovy provider who’s also trusted by the NHS to deliver weight-loss services
Second Nature Trustpilot rating 4.8/5
Second Nature Trustpilot reviews 6,888 (as of January 2024)
Availability In stock
Description Once weekly weight-loss injection
Administration Subcutaneous injection (multiple sites like the arm, stomach, or leg)
Presentation Injection pen
Available dosage 0.25 mg, 0.5 mg, 1 mg, 1.7 mg, 2.4 mg
Drug class GLP-1 receptor agonist
When pregnant/breastfeeding Not permitted


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