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Topics

Choose the topic that suits you. Each topic gathers the main peptides, the questions people ask and what the research shows.

Weight and metabolism

The best-researched peptides of all, tested in studies with thousands of people.

  • How much weight do people lose?

    In the largest studies, participants lost on average about 15 per cent with semaglutide and up to 21 per cent with tirzepatide. In the highest dose group for retatrutide, the figure was 25 per cent.

  • How do these medicines work?

    They mimic hormones the gut releases after a meal, such as GLP-1 and GIP. These hormones help you feel full and help the body control blood sugar.

  • Do the benefits go beyond weight?

    Yes. In a study of more than 17,000 people, fewer had a heart attack or stroke or died of cardiovascular disease on semaglutide. With retatrutide, knee pain in osteoarthritis and breathing pauses in sleep apnoea went down.

  • How do I get one of these medicines?

    Talk to your doctor. With a prescription, you collect semaglutide or tirzepatide at a pharmacy or order from an approved Norwegian online pharmacy.

All about weight and metabolism

Training and recovery

Research on healing and recovery.

All about training and recovery

Skin, ageing and wellbeing

Copper peptides and research on ageing skin, joints, gut and brain.

  • What does GHK-Cu do for the skin?

    This small copper peptide occurs naturally in the body and is a common ingredient in creams and serums. In the laboratory, it has shown effects on skin healing and connective tissue renewal.

  • What about the gut and the brain?

    KPV, three amino acids from an anti-inflammatory hormone, calmed gut inflammation in mice. Semax has been studied in patients after stroke, with somewhat faster recovery.

All about skin, ageing and wellbeing

Find what matters to you

The topics group the peptides by what people are usually interested in. Under each topic you will find the peptides, the most common questions and the best pages to read next.

The three topics

Weight and metabolism

Here you will find the new medicines for obesity and type 2 diabetes, semaglutide, tirzepatide and retatrutide, and MOTS-c, a peptide the body makes itself. This is the field where peptides have come furthest. In the largest studies, participants lost on average between 15 and 25 per cent of their body weight, depending on the medicine and dose.[1][2][3] Go to Weight and metabolism

Training and recovery

Here you will find the peptides researched for healing of tendons, muscles and wounds: BPC-157, TB-500, thymosin beta-4 and CJC-1295 with ipamorelin. Several have promising results in animal studies, and thymosin beta-4 has been tested against placebo in humans.[4][5] Go to Training and recovery

Skin, ageing and wellbeing

Here you will find the peptides in skincare and health food, such as GHK-Cu, and some peptides researched for skin, gut and brain. Go to Skin, ageing and wellbeing

Looking for something specific?

If you are looking for a particular substance, the quickest way is the search or the Peptides page in the menu. If you want to understand the basics first, What are peptides? is a good place to start.

Questions and answers

Why is a peptide listed under only one topic?

We place each peptide where it is most often discussed. Many peptides are studied for several things, and everything is on the peptide page.

Which topic has the most research?

Weight and metabolism. The medicines here have been tested in large studies with thousands of participants.

Will there be more topics?

Yes. We add new topics as we write about more peptides.

Sources

  1. [1]

    Wilding JPH, Batterham RL, Calanna S, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. N Engl J Med. 2021.

    PMID 33567185DOIRCT · n = 1,961 · Funding or ties: Novo Nordisk.

  2. [2]

    Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide Once Weekly for the Treatment of Obesity. N Engl J Med. 2022.

    PMID 35658024DOIRCT · n = 2,539 · Funding or ties: Eli Lilly.

  3. [3]

    Jastreboff AM, Kaplan LM, Davies MJ, et al. Retatrutide, a Triple Hormone Receptor Agonist, for Treatment of Obesity. N Engl J Med. 2026.

    PMID 42814954DOIRCT · n = 2,339 · Funding or ties: Eli Lilly.

  4. [4]

    Vasireddi N, Hahamyan H, Salata MJ, et al. Emerging Use of BPC-157 in Orthopaedic Sports Medicine: A Systematic Review. HSS J. 2025.

    PMID 40756949DOIMeta-analysis

  5. [5]

    Guarnera G, DeRosa A, Camerini R. The effect of thymosin treatment of venous ulcers. Ann N Y Acad Sci. 2010.

    PMID 20536470DOIRCT · n = 73