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Orlistat for weight loss

Robbie Puddick
Written by

Robbie Puddick

Medically reviewed by

Fiona Moncrieff

3 min read
Last updated April 2024

Jump to: What is orlistat? | Should I buy Orlistat? | Take home message

Orlistat (Xenical/Alli) has been shown to lead to a weight loss of 4% of body weight after three months and around 8% after one year.

It’s generally well-tolerated, with fewer than 10% of people taking orlistat stopping the medication due to adverse effects.

However, research has shown that other weight-loss medications lead to significantly more weight loss, with orlistat often performing worse than other medications, such as liraglutide (Saxenda).

In a review comparing orlistat with four other weight-loss medications, including liraglutide, orlistat was found to be the least likely to lead to more than 5% of weight loss.

Additionally, recent GLP-1 medications like semaglutide (Ozempic) lead to a more significant weight loss of 10-20% after one year.

At the same time, a clinical trial with 237 participants investigated the impact of orlistat in a real-world setting to determine adherence to the medication and whether they were well tolerated.

The results showed that participants lost around 4% of body weight after three months. 80% of participants reported being satisfied with the drug due to its positive effect on weight loss.

This suggests that despite its modest effects on weight loss, the medication’s tolerability may support some people to stay on it for longer and change their diet and lifestyle.

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What is orlistat?

Orlistat is a lipase inhibitor. Lipases are gut enzymes that break down fat from food, enabling the gut to transport fat into the body to be burnt for energy or stored in our fat cells for later use.

Orlistat blocks lipases, preventing some of the dietary fat from our meals from being digested. This leads to fewer calories being absorbed, which can support weight loss.

Orlistat is a prescription medication produced by two pharmaceutical companies in the UK:

  • GlaxoSmithKline: Alli, 60 mg and available over the counter (no prescription)
  • Roche: Xenical, 120 mg and available with a prescription

However, it’s recommended that you consult with a healthcare professional or a pharmacist before purchasing weight-loss medications.

Should I buy orlistat?

Lipase inhibitors like Xenical and Alli can lead to weight loss of 4-8% after one year, alongside changes to diet and lifestyle.

They’re also well-tolerated, with human clinical trials indicating less than 10% of people stop taking the medication due to adverse effects.

However, all medications come with risks and rewards, and not everyone is suitable for weight-loss medications like orlistat.

Deciding to start a new medication is a highly personal choice. So, ultimately, it depends on whether you believe it’s the best decision for your health going forward.

All weight-loss medications are designed to be taken alongside changes to your lifestyle. Without this, the effects of the drug will not last, and you’ll likely regain any weight you lose in the future.

Take home message

Orlistat leads to a modest weight loss of around 4-8% after one year and is generally well-tolerated, with fewer than 10% of people on the medication stopping it due to adverse effects.

Recent innovations in weight-loss medications mean there are now more options than ever for people who need extra support.

However, these drugs shouldn’t be seen as miracle cures; they’re not designed to be used for life.

They’ve been designed to be taken alongside lifestyle changes that will enable you to eventually come off the medications and maintain your lower weight for the long term.

GLP-1s are safe and effective for most people in the short to medium term, but they’re not for everyone and shouldn’t be used as a fast track for success.

At Second Nature, we’re not against using medications to support people in making healthy changes and reducing their risk of chronic disease.

However, we don’t recommend using medications as a reason not to make healthy lifestyle changes. The causes of obesity and type 2 diabetes aren’t merely rooted in biology but also in psychology and sociology.

With these medications, you may lose weight and reduce blood sugar levels. But will you be happier? Will you be more fulfilled? Will you be content with your life and social relationships?

For that, you may need to consider a lifestyle change.

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