What are peptides for weight loss?

Peptides play a vital role in how our bodies work, from supporting skin health and tissue repair to joint care [1, 2]. But did you know they’re also the key component in some types of weight management medication?

In this article, we'll explain what peptides are, how they work for weight management and what you need to know if you're considering treatment.

Article Summary:

• Peptides are short chains of amino acids which form proteins. They act as the body's "messengers", performing vital signalling to different parts of the body to support repair, growth and regulation.
• In recent years, certain types of peptides have also been shown to clinically support weight management. These include GLP-1 medications like semaglutide and tirzepatide.
• Like any medication, injectable peptides may cause side effects. However, if you're considering treatment, it's really important you have your treatment approved and prescribed by a licensed healthcare professional. Unauthorized peptide treatments carry a significant health risk.

What are peptides?

Peptides are short chains of amino acids (small organic compounds) which link together and act as “messengers” in your body. [3, 4] They signal your organs, tissues and cells to perform specific functions, like stimulating the release of hormones, repairing tissues and regulating metabolism. [5, 6, 7]

This means that peptides are essential for processes like muscle recovery. [8] But they may also be beneficial for another function: weight management. [9]

It’s worth noting that long chains of amino acids are what forms protein, which is also helpful in supporting long-term weight management goals. [10]

How can peptides support weight loss?

So, what do peptides have to do with weight loss? Recent research shows certain types of injectable peptides may influence how your body processes hunger signals. [8]

In fact, if you’re considering weight management treatment, you may already be familiar with some of them.

Medications like semaglutide and tirzepatide are peptide‑based drugs. In essence, they’re modified versions of natural hormones (GLP‑1 and GIP). They’re also regulated as prescription medicines, rather than the “peptide supplements” you may have heard about on social media. [11]

These GLP-1 medications mimic the GLP-1 and GIP hormones in your body. They send signals to your brain to:

• Reduce hunger by signalling to your brain that you’re full
• Make you feel fuller for longer by slowing digestion
• Silence “food noise” by influencing the “reward system” part of your brain, to reduce cravings and food-focused thoughts
• Stabilize your blood sugar by helping your body release insulin more effectively after meals, reducing glucose spikes [8, 12, 13, 14, 15]

This is why, in recent years, GLP-1 medications have gained a lot of interest as a clinically-led approach to weight management.

Do peptides for weight loss actually work?

Studies have shown that GLP-1 treatments can be effective for weight loss and weight management, when used alongside a healthy diet and increased movement. [13, 14] However, results may vary from person to person and also depend on other factors like:

• Your starting weight
• Any medical conditions you may be living with
• How long you remain on treatment
• Any other positive lifestyle changes you make, both during and after treatment

It's also important to remember that authorized peptide-based medicines, like semaglutide, are strictly regulated by Health Canada. They're only available on prescription, and you'll need to meet certain thresholds to be eligible for treatment. We'll explain more on why that matters in the next section.

Are peptides safe for weight loss?

Like any medication, there are certain side effects and risks to bear in mind when taking injectable peptides. However, when purchased from a licensed pharmacy with a valid prescription, and taken correctly under the care of a licensed healthcare professional, peptides are generally a safe and effective way to support weight management.

Health Canada has issued warnings about the dangers of purchasing unauthorized injectable peptides from unlicensed online sellers. This is because these medications haven't been assessed for safety, efficacy or quality by Health Canada, and may pose serious health risks. [16]

Remember that treatment with peptides may not be suitable for everyone. You should not take GLP-1 medications if:

• You have a personal or family history of medullary thyroid carcinoma (MTC), a rare form of thyroid cancer
• You live with Multiple Endocrine Neoplasia type 2 (MEN 2)
• You live with type 1 diabetes
• You have a known allergy to any of the ingredients in the treatment
• You're pregnant, breastfeeding or trying to conceive [17, 18]

During your consultation, it's important to share your full medical history with your healthcare provider. This is because if you've previously experienced certain conditions, like pancreatitis or kidney or liver problems, treatment should be taken with extreme caution. [17, 18] You should also read your Patient Medication Information (PMI) sheet in full before beginning treatment.

Can peptides cause side effects?

Yes, peptides used for weight management can cause side effects. However, most of the time any adverse events are mild, short-lived and can be managed from the comfort of home. [19]

Side effects may include:

• Nausea
• Diarrhea
• Vomiting
• Stomach pain
• Constipation
• Belching
• Bloating
• Flatulence
• Indigestion
• Injection site reaction (like bruising, pain, irritation, itching and rash)
• Mild allergic reaction (like itching, rash and hives)
• Reflux or heart burn [17, 18]

Additionally, specific types of GLP-1 may also cause:

• Increased heart rate
• Dizziness
• Headaches
• Gallstones
• Tiredness
• Change in skin sensation [17, 18]

For more information on the listed side effects of specific treatments, please refer to the Patient Medication Information (PMI) sheet for your specific medication. [17, 18]

If you're currently receiving treatment for type 2 diabetes, you may also be at a higher risk of developing low blood sugar (hypoglycemia). [17, 18] While most cases are mild, if not treated hypoglycemia can be a dangerous condition. You can learn more about hypoglycemia, and how to treat it, on Diabetes Canada's dedicated webpage.

If you have concerns about any of these side effects, or if they're persistent or uncomfortable, speak to your healthcare provider or call 811.

Serious side effects

Certain types of weight loss medication may also cause serious side effects. If you experience any of the following, stop treatment immediately and seek urgent medical attention by attending your closest ER or dialling 911:

• Diabetic eye disease (Diabetic retinopathy): blurred vision, lines in vision
• Severe allergic reaction: breathing problems, swelling of your throat, lips, face and tongue and a fast heartbeat
• Pancreatitis: prolonged severe abdominal pain with or without vomiting
• Dehydration that can cause sudden kidney failure: dark yellow and strong-smelling pee, feeling extremely thirsty, feeling dizzy or lightheaded
• Severe hypoglycemia: disorientation and confusion, loss of consciousness or seizure
• Sudden gallbladder problems: severe abdominal pain, yellowing of your skin or high fever with chills
• Sudden vision loss, which may be painless, blurred or cloudy vision, or severe headache. These can be signs of a serious condition caused by swelling of your eye nerves, called non-arteritic anterior ischemic optic neuropathy (NAION). [17, 18]

Fortunately, most of these serious side effects are uncommon or rare. [17, 18] However, identifying the signs of a potentially serious side effect early may help you get the urgent care you need, quickly.

For more information on the serious side effects of specific treatments, please refer to the Patient Medication Information (PMI) sheet. [17, 18]

How can I support my weight loss journey?

Any weight management treatment should be paired with positive, sustainable lifestyle changes. This means building healthy, long-lasting habits that can fit into your daily routine:

• Sleep: Health Canada recommends that adults aim to get 7-9 hours of sleep each night. This may support your hormonal balance and energy levels, and also reduce food cravings. [20, 21] You should also avoid any "blue light" an hour or so before bedtime. [22] Instead of watching TV or scrolling on your phone, reading a book or taking a bath may help you relax before bed.
• Eat: Health Canada advises eating balanced, healthy, non-processed meals, featuring a wide range of nutrients. These include carbohydrates (like wholewheat pasta and sweet potatoes), protein (like chicken and tofu), healthy fats (like nuts and avocados) and fruits and vegetables. [23] Eating little and often may also help to minimize digestive side effects, like nausea.
• Move: Health Canada recommends that adults get a total of 150 minutes of moderate to vigorous activity each week. [24] This could include anything that increases your resting heart rate, like a brisk walk or increasing your movement while completing household chores.

Are peptides for weight loss right for me?

If you're considering weight management treatment, you may have further questions about your medication options. Our friendly team is here to support you at every stage of your journey.

Find out which treatment may be suitable for you with MedExpress.

References

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