Peptides May Be Your Answer to Fuller, Thicker Hair (2025)

Yes, peptides can actually support healthy hair growth, though there are some caveats. “The right peptides can help with hair growth by stimulating blood flow to the scalp, reducing inflammation to protect follicles, stimulating collagen and extracellular matrix production around the follicle and signaling hair follicles to stay in the growth phase,” says Dr. Azizzadeh. But hair growth—and hair loss—are complex, and peptides alone may not be your answer to stronger strands. “Peptides support active follicles only,” Yates reminds us. “If the follicle is no longer active, then peptides or any ingredients (topical or ingestible) cannot reanimate a follicle that is essentially ‘dead.’"

There are many reasons why hair growth could be inhibited, including genetic, hormonal, environmental, and systemic factors, so it’s important to consider a multi-pronged treatment approach. That could include in-office or at-home topical exosomes, oral supplements for hair growth, and other options—it’s best to see a dermatologist, trichologist, or other hair expert for a customized plan.

While there are numerous peptides found in topical formulas, our experts agree there are two main types of peptides for hair growth:

• Copper peptides (GHK-Cu): You likely recognize copper peptides from their use in skin-care formulas; they’re efficacious in scalp products, too. “Copper peptides work in multiple ways, such as stimulating blood flow to the scalp, increasing the size of the hair follicle, extending the anagen or growth phase on the hair cycle, having anti-inflammatory and wound-healing properties, and boosting collagen,” says Dr. Azizzadeh. This ingredient is actually a popular choice in clinical settings, where providers can administer copper peptides via injection, or apply them to the scalp after microneedling.
• Biomimetic peptides: These are synthetic peptides designed to mimic naturally-occurring peptides, explains Yates, who notes that they can help improve blood flow to support healthier hair growth as well as strengthen the hair follicle. A stronger follicle acts as a better “anchor” for the hair, reducing shedding and extending the hair’s longevity. There are a handful of commonly-used peptides that fall into this category, including acetyl tetrapeptide, biotinoyl tripeptide-1, and oligopeptide-41 (and they’re often often found in trademarked ingredient complexes, such as Procapil and Capixyl).

The best foundation for hair growth is a clean scalp, says Yates. “Would you ever go days and days without washing your face? You wouldn’t, because the results would be horrific,” she says. “But that is what you do when you fail to wash your hair.” Not all hair types can handle being washed daily, making scalp rinses extra important for those who wear protective styles. Just don’t be too reliant on dry shampoo, as it can clog the follicle and lead to hair loss over time.

Remember that any product you apply to your scalp will penetrate more effectively if there’s no grime in the way. Ideally, you’d wash your hair a minimum of two to three times a week, says Yates, spending extra time massaging your scalp when shampooing. This helps promote blood flow (great for promoting hair growth!) and ensures all product, excess sebum, and dead skin cells are removed. Don’t feel the need to use a scalp scrub, as these can often be too harsh and damage the follicle—that extra massage when cleansing is enough.

While you should always follow the product’s instructions for use, most hair growth formulas will recommend daily or even twice daily application for at least eight to 12 weeks to see results, says Dr. Azizzadeh. You’ll want to apply it once your hair is clean and dry, possibly after dermarolling your scalp. “This can be helpful for penetration,” says Dr. Mian. Make sure you’re applying the peptide serum not to your hair, but to the root at the scalp, massaging it in. Increasing circulation as you massage will not only improve distribution, but increase absorption. “Several studies have shown simple daily scalp massage has helped to improve scalp health and helps to decrease hair fall,” adds Yates. Once you’re done, don’t wash your hair for at least several hours—and if you have nowhere to be, consider slapping on a plastic shower cap. “Covering the head in plastic adds warmth to further promote scalp circulation,” explains Dr. Kahn.

First, consider the format. Our experts generally recommend peptides for hair growth in a serum rather than a shampoo as these formulas are left on rather than washed off, giving your follicles more time to absorb them. Then, examine the ingredients. The best products will contain a blend of peptides, says Dr. Mian. “Peptides show synergy and work well together, so I would look for a serum with a combination of peptides,” she explains.

While peptides are the stars here, the supporting cast of ingredients is also important in promoting a healthier scalp. “Good scalp health leads to perfect follicle fitness, which provides support for hair growth,” says Yates. Kahn recommends caffeine and peppermint, both of which have invigorating properties that can stimulate blood circulation. Tea tree has antimicrobial and anti-inflammatory benefits, making it ideal for flaky scalps, while rosemary oil has anti-inflammatory and antioxidant properties that protect against stress on the follicle. If you have a dry or dehydrated scalp, consider looking for a formula that contains hydrating hyaluronic acid and soothing aloe vera; those prone to oily scalps can seek out witch hazel (which helps break break down product buildup) and sebum-regulating zinc.

Lastly, make sure the product is one you like enough to use daily. “Consistency is key as it can take several weeks to months to see results,” Kahn reminds us. Trust the process!

• Kerry Yates is a trichologist and the founder of Colour Collective.
• Dr. Amanda Kahn is a board-certified internist and longevity expert in New York, NY.
• Dr. Kiran Mian is a board-certified dermatologist at Hudson Dermatology and Laser Surgery in New York, NY.
• Dr. Babak Azizzadeh is a board-certified facial plastic surgeon in Beverly Hills, CA.