Peptides For Weight Loss: How Do They Work?

Peptides are essential molecules that help your body function. But did you know they’re also a key ingredient in some weight loss treatments? Let’s take a look at what peptides are, how they work and what you need to consider when taking them.

Article Summary:

• Peptides are an essential part of how our bodies function. They act as “messengers” for our cells, to help them heal and grow.
• GLP-1 receptor agonists like semaglutide and tirzepatide have also shown significant effectiveness in weight loss and weight management treatment.
• Peptides should only be prescribed for weight loss by registered healthcare professionals.

What are peptides?

Peptides are small chains of amino acids, which make up proteins in your body. Think of peptides as your body's "messengers": they travel around your body, carrying messages from one part to another. These messages tell your cells how to grow, communicate and heal. [1]

Peptides are essential for functions like muscle growth and cell recovery. [2] And now, clinical evidence also suggests that some can play an important role in weight loss and weight management. [3] But how?

How do peptides help with weight loss?

If you're considering weight loss or weight management treatment, you may have heard of GIP and GLP-1s. But did you know that these are, in fact, peptides?

Some peptides, including GIP and GLP-1 receptor agonists like semaglutide, as well as the dual GIP/GLP-1 receptor agonist tirzepatide, may support weight management. [4] [5] [6] This is because they mimic the GLP-1 hormone in your body, sending signals to your brain to:

• Regulate your blood sugar. This impact on your blood sugar levels may help you use glucose in your body for energy.
• Slow your digestion and improve your satiety response. This may support appetite regulation to help you feel fuller, control "food noise" and prevent overeating. [7] [8] [9]

Are peptides effective for weight loss?

GLP-1 receptor agonists, in particular tirzepatide and semaglutide, are considered some of the most effective agents for weight loss. [10] [11]

For example, clinical evidence from a human trial study shows that a person could lose an average of 22.5% of their body weight in 72 weeks (1 year, 5 months) when they take tirzepatide.* [5]

Likewise, clinical evidence also shows that a person could lose an average of 20.7% of their body weight in 72 weeks (1 year, 5 months) when they take semaglutide.** [6]

However, the effectiveness of peptides for weight loss may vary from person to person. It depends on various factors, like your starting weight, how long you take the treatment for and the positive, sustainable lifestyle changes you choose to make during and after treatment. We'll explain what these changes may look like below.

How can I support my treatment?

GLP-1 treatments should be used as part of a wider weight management programme, including positive lifestyle changes which support healthier habits. And the best way to support your treatment is to focus on gradual, long-term and sustainable results.

• Movement: Adding more mindful movement into your daily routine may support long-term weight maintenance, while also improving your overall health and wellbeing. If you're new or returning to exercise, try gently building up your stamina and strength. Listening to your body and focusing on consistency over quick results is the best way to achieve lasting change.
• Sleep: Aim for 7-9 hours of quality sleep each night to support your hormonal balance and metabolism.
• Mindful eating: Rather than following a specific "diet", try to build your eating habits around balanced choices. This might mean increasing your fibre (like fruits and vegetables and wholegrain cereals) and protein (like lean meats, eggs and dairy) to support satiety (feeling full).

How long does it take to see results?

Because everyone responds differently, it can be hard to say for certain how long it would take for an individual to see results.

On average, you may expect to start seeing results by the fourth week of treatment. [12] However, this isn't guaranteed. After the first 4 weeks, your healthcare provider may increase your dose to support your ongoing treatment (we call this "titration".) [8] [9] Clinical evidence suggests that long-term use may be more beneficial to support weight loss and management. [13]

Are peptides suitable for me?

You may be eligible for weight loss treatment if:

• Your BMI is 30+
• Your BMI is 27+ and you're living with a weight-related condition, like type 2 diabetes or high blood pressure.
• In some cases, you may be eligible if your BMI is 25+.

As with any prescription medication, your eligibility is subject to an assessment by a registered healthcare provider. They will determine if treatment is right for you, and provide guidance on your options.

There are some circumstances where the use of peptides for weight loss and weight management may not be right for you.

You shouldn’t use peptides for weight loss if you're pregnant, trying to conceive or breastfeeding. If there's a chance you could become pregnant while taking peptides for weight loss, it's recommended you use contraception for the duration of your treatment. You should also stop treatment at least 2 months before trying to conceive. [8] [9]

You should also tell your doctor if you've experienced kidney injury, or have any kidney problems.

When discussing weight loss treatment with your healthcare provider, it's important to share your full medical history. For more information on treatment and whether it's right for you, speak to your healthcare provider. Also be sure to read your patient information leaflet (PIL) in full before starting treatment.

Are peptides safe for weight loss?

When used as prescribed, and with the approval and guidance of a registered healthcare professional, peptides are a safe, licensed form of treatment which may support weight loss and weight management. [11]

However, it’s important to have a clinical consultation before starting a weight loss treatment. This is to make sure that you get the right treatment for you. Peptide treatment for weight loss and weight management requires a prescription, and you'll need to check in with a clinician regularly to monitor your progress.

You should only access GIP and GLP-1 medications via a registered healthcare provider. This is to make sure you're using a licensed medication which is safe for use. [14] Unfortunately, there are increasing reports of illicit weight loss treatments infiltrating the market. [15] Buying from unregulated sellers may put your safety at risk.

As with any medication, you may experience side effects when taking peptides. Let's explore the most common side effects, as well as the rarer, but more severe, adverse effects to look out for.

What are the side effects of using peptides for weight loss?

GIP and GLP-1s may cause side effects. [8] [9]

Very common side effects of semaglutide (which may affect more than 1 in 10 people) include:

• Nausea
• Diarrhoea
• Vomiting
• Stomach pain
• Constipation [8]

Very common side effects of tirzepatide (which may affect more than 1 in 10 people) include:

• Headache
• Nausea
• Vomiting
• Diarrhoea
• Constipation
• Stomach pain
• Feeling weak or tired [9]

These side effects are most common in the first few weeks of treatment. [8] [9] If you experience them, our clinical team is on hand to support you.

It's also important to be aware of the more severe side effects of peptide weight loss treatment.

If you experience any of the following while taking semaglutide, seek immediate medical attention:

• Complications of diabetic eye disease (diabetic retinopathy). If you have diabetes, you should let your doctor know if you experience any eye problems,like changes in vision, during treatment. (Common, may affect up to 1 in 10 people).
• Inflamed pancreas (acute pancreatitis) which could cause severe pain in your stomach and back which doesn’t go away. (Uncommon, may affect up to 1 in 100 people).
• Kidney or bladder stones (rare, may affect up to 1 in 1,000 people).
• Severe allergic reactions. Symptoms may include breathing problems, swelling of face, lips, tongue, and/or throat with difficulty swallowing, wheezing, fast heartbeat, pale and cold skin, feeling dizzy or weak. (Rare, may affect up to 1 in 1,000 people).
• Hip fractures (rare, may affect up to 1 in 1,000 people).
• An eye condition called non-arteritic anterior ischaemic optic neuropathy (NAION), which may cause loss of vision without any pain (very rare, may affect up to 1 in 10,000 people).
• Bowel obstruction, a severe form of constipation (frequency unknown). [8]

If you experience any of the following while taking tirzepatide, seek immediate medical attention:

• Inflamed pancreas (acute pancreatitis) which could cause severe pain in the stomach and back which does not go away. (Uncommon, may affect up to 1 in 100 people).
• Severe allergic reactions. Symptoms may include breathing problems, rapid swelling of the lips, tongue and/or throat with difficulty swallowing and a fast heartbeat. (Rare, may affect up to 1 in 1 000 people). [9]

For a full list of potential side effects while taking a weight loss treatment, please refer to your patient information leaflet (PIL) or speak to your healthcare provider.

Peptides for weight loss: are they right for me?

If you're considering whether to begin a weight loss or weight management programme, you may have more questions about peptides. Our friendly team is here to guide, advise and confirm your eligibility. We're also here to support you, no matter where you are in your weight management journey.

Find out what treatment is suitable for you with MedExpress.

*The evidence comes from SURMOUNT-1, a 72-week clinical trial in adults with a BMI of 27 or above using Mounjaro 15mg. Studies in people with lower BMIs are limited, so results and safety are less certain. Weight loss cannot be guaranteed.

**The evidence comes from STEP UP, a 72-week clinical trial in adults with a BMI of 27 or above using Wegovy (semaglutide 7.2mg). Studies in people with lower BMIs are limited, so results and safety are less certain. Weight loss cannot be guaranteed.

References

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