Understand what each peptide does — and how it may benefit you

BPC-157

An experimental synthetic peptide made up of 15 amino acids.

It is derived from a protective protein found in human stomach juice and has attracted attention for its potential role in tissue repair, injury recovery, and inflammation.

Semaglutide

A prescription medication primarily used for weight loss, blood sugar control, and improving certain aspects of metabolic health.

It belongs to a class of medications called GLP-1 receptor agonists. It works by mimicking a natural hormone in your body that helps regulate appetite, digestion, and blood sugar.

TB-500

A synthetic peptide associated with a naturally occurring protein in the body called Thymosin Beta-4 (Tβ4).

It is commonly marketed in the fitness, bodybuilding, and recovery communities as a peptide that may help with muscle repair, tendon and ligament recovery, inflammation, and tissue healing.

Retatrutide

An experimental weight-loss medication still being studied in clinical trials.

It is considered one of the most promising next-generation medications for obesity and metabolic health because it targets three different hormone receptors instead of one.

It is sometimes called a triple agonist because it activates GLP-1, which reduces appetite and helps you feel full; GIP, which helps regulate insulin and blood sugar and influences metabolism; and Glucagon, which may increase energy expenditure and influence how the body processes stored energy.

Unlike Semaglutide, which targets GLP-1, and Tirzepatide, which targets GLP-1 and GIP, Retatrutide targets all three.

Wolverine (BPC-157 & TB-500)

A combination of two experimental peptides: BPC-157 and TB-500 — also called the Wolverine Stack.

It has become popular in bodybuilding, fitness, and injury-recovery communities because both peptides are being investigated for their potential roles in tissue repair and healing.

The name comes from the fictional character Wolverine, who is known for his ability to heal rapidly.

Glow (GHK-Cu · BPC-157 · TB-500)

A combination of three experimental peptides, also called the GLOW Stack.

It is a combination of three experimental peptides: GHK-Cu, a copper peptide primarily studied for skin health, collagen production, and tissue repair; BPC-157, studied for potential tendon, ligament, muscle, and gastrointestinal healing; and TB-500, studied for potential tissue repair, cell migration, and wound healing.

It is marketed as a combination for skin rejuvenation, hair health, anti-aging, and physical recovery.

Klow (GHK-Cu · BPC-157 · TB-500 · KPV)

A four-peptide combination studied for skin healing, inflammation, and tissue repair.

It is a combination of four peptides: GHK-Cu, a copper-binding peptide studied for skin health, collagen, and tissue remodeling; BPC-157, studied for potential tendon, ligament, muscle, and gastrointestinal healing; TB-500, studied for potential tissue repair and cell migration; and KPV, a short tripeptide fragment (lysine–proline–valine) derived from a naturally occurring hormone called alpha-MSH.

KPV is the component that sets Klow apart from similar blends: research on KPV has focused on its potential anti-inflammatory properties, including studies involving inflammatory skin conditions and intestinal inflammation. The blend as a whole is marketed for skin healing, gut health, inflammation, and physical recovery.

Klow is an experimental combination. Its individual components are each at different stages of research, and published human research on the combination itself is limited to nonexistent — the benefits claimed for the blend are not established.

GHK-Cu

A copper-binding peptide studied for skin renewal and tissue remodeling.

Commonly called Copper Peptide, it is a naturally occurring copper-binding peptide made up of three amino acids: glycine, histidine, and lysine. It is naturally present in human blood, saliva, and urine, and has attracted attention in skincare, anti-aging, hair growth, and tissue-repair research.

GHK-Cu is particularly interesting because copper plays an important role in collagen production, skin repair, and other biological processes. Potential benefits being studied include improved skin texture, a reduced appearance of fine lines, better skin elasticity, and improved skin firmness.

NAD+

A coenzyme central to cellular energy, studied for healthy aging.

Nicotinamide Adenine Dinucleotide is a molecule found in every living cell in your body. It plays a critical role in converting food into energy, supporting cellular repair, maintaining DNA health, and regulating cellular processes that keep cells functioning properly.

It is often promoted as a way to improve energy, mental clarity, recovery, and healthy aging. Cellular energy: it helps mitochondria convert nutrients into usable energy (ATP) and is essential for normal cellular energy production. DNA repair and cellular health: it is used by enzymes involved in DNA repair and cellular stress responses.

Healthy aging and longevity: researchers are studying NAD+ because it supports proteins called sirtuins, which regulate cellular maintenance and metabolism — though whether boosting NAD+ extends human lifespan is not established. Brain function: it is important for normal brain-cell function, and researchers are investigating whether increasing it can support cognitive health, but meaningful improvements in memory or focus have not been reliably demonstrated. Muscle recovery and metabolism: it participates in energy metabolism and muscle-cell function, and whether supplementation meaningfully improves athletic performance or recovery remains uncertain.

Melanotan II

A melanocortin peptide studied for skin pigmentation and related appetite effects.

Commonly called MT-2, it is a synthetic peptide that stimulates your body's melanocortin receptors, particularly those involved in producing melanin, the pigment responsible for skin color. It is commonly marketed as a tanning peptide, sometimes called the Barbie Peptide.

Unlike many of the other peptides we've discussed, Melanotan II is primarily associated with skin pigmentation and sexual function rather than tissue repair or weight loss. Darker skin pigmentation: it stimulates melanin production, potentially producing a darker complexion without relying entirely on sun exposure. Increased sexual arousal: it activates melanocortin receptors involved in sexual function, and small early studies reported increased sexual arousal and spontaneous erections.

Reduced appetite: some users experience appetite suppression, though it is not an established or approved weight-loss treatment. Tanning without traditional sun exposure: it can stimulate pigmentation without requiring UV exposure to initiate the process — however, this does not mean it protects you from sun damage.

Tirzepatide

A prescription dual GIP/GLP-1 receptor agonist studied for weight and metabolic health.

It is a prescription medication used for weight loss, blood sugar control, and improving metabolic health, and is considered one of the most effective medications currently available for treating obesity. It belongs to a class of medications called dual GIP/GLP-1 receptor agonists — it activates two hormone receptors: GLP-1, which reduces appetite, slows stomach emptying, and helps you feel full longer; and GIP, which helps regulate insulin secretion and blood sugar and works alongside GLP-1 to improve metabolic control.

Together, these effects can help you eat less, lose weight, and improve blood sugar regulation. You may recognize it by its two brand names: Zepbound, FDA-approved for chronic weight management in eligible adults and certain patients with obesity-related obstructive sleep apnea; and Mounjaro, FDA-approved for improving blood sugar control in adults with type 2 diabetes.

Significant weight loss: it helps reduce appetite, cravings, and calorie intake — clinical trials have demonstrated average weight loss of approximately 15–21% over 72 weeks, depending on the dose. Improved blood sugar: it helps lower blood glucose and A1C levels in people with type 2 diabetes. Improved metabolic health: it can improve several metabolic risk factors, including waist circumference, blood pressure, and triglycerides.

Potential liver benefits: weight loss with tirzepatide can improve liver fat and metabolic dysfunction, and it has also demonstrated benefits in clinical trials for certain patients with fatty liver disease (MASH). Sleep apnea improvement: Zepbound is FDA-approved for moderate-to-severe obstructive sleep apnea in adults with obesity.

Tesamorelin

An FDA-approved GHRH analog studied for reducing abdominal fat and body composition.

It is a synthetic analog of growth hormone-releasing hormone (GHRH) — a naturally occurring hormone that signals the pituitary gland to release growth hormone.

It is an FDA-approved prescription medication (brand name Egrifta) for reducing excess abdominal fat in people with HIV-associated lipodystrophy. That is its only approved use — an important distinction from the off-label promotion it sometimes receives.

Potential benefits being studied include reduced visceral (deep abdominal) fat and improved body composition. It is also discussed in fitness communities for growth hormone release, but that is off-label use and should only ever be considered under medical supervision.