Jennifer Linder, MD, on recent breakthroughs in skin care product ingredients, usage, and trends

Finding the “perfect skin care solution” for all types of skin used to be easy—not all skin types had a good solution. That is changing rapidly as new skin care formulations flood the professional and consumer market. The technology factors in a person’s skin type—ethnicity, lifestyle, and genetics—can be sorted out in order to provide recommendations that are the “perfect fit” for virtually all patients. How did we get here so fast?

Within just the past couple of years, the science of skin care matured and manufacturers have combined chemical and organic/natural ingredients in frankly new and exciting formulations.

Although a multitude of ingredients are marketed as antiaging remedies, what can physicians and their patients really believe? Jennifer Linder, MD, a board-certified dermatologist, fellowship-trained Mohs skin cancer surgeon, biomedical engineer, and chemist, recently spoke with PSP about current research, proven ingredients, and the future of skin care and antiaging remedies.


In the midst of new product launches and claims about a variety of new ingredients and their effects on the skin, Linder emphasizes the importance of thorough daily care and moisturization for patients’ skin. Many consumers look for a “cure-all” in topical skin care products, but good moisturization can mend—or at least mask—a multitude of imperfections, she explains. Hydrated skin looks better and overall works more effectively than dehydrated skin because moisture heals barrier deficiencies and helps keep the skin’s outside layer functioning appropriately.

“Most great skin care products have great moisturizers,” Linder says. A good moisturizer has two components: an occlusive moisturizer that acts as a sealant and a humectant that acts as a sponge. These two components help skin retain moisture as well as receive additional moisture from the topical product itself, she adds.

One of the ingredients used in skin care products to help skin retain moisture is hyaluronic acid. Hyaluronic acid helps the skin retain moisture and can help to diminish the appearance of fine lines and wrinkles, Linder says, adding that the moisture itself plumps up skin cells and can brighten the overall appearance of the skin.

She encourages skin care professionals and physicians to educate patients on the overall care of their skin—not just repairing current damage. In general, the best way to take care of skin is to prevent further damage—appropriate cleansing, moisturization, and daily use of a sunscreen are the foundation of any skin care regimen.


The use of peptides in skin care products has been increasing in recent years. Peptides are chains of amino acids that change cell behavior based on signals. They have been heavily researched and are currently used in so-called antiaging skin care products.

A variety of peptides have been shown to slow cell breakdown, and some studies now indicate that certain peptides can in fact trigger new cell growth, according to Linder. For example, Acetyl hexapeptide-8 has been shown in some studies to trigger collagen production. Acetyl hexapeptide-8 is considered a neurotransmitter-affecting peptide that inhibits soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE) complex.

Linder has used Acetyl hexapeptide-8 with her patients to achieve very favorable results. “Basically, this ingredient is applied to areas of dynamic wrinkling—crow’s feet, forehead lines, frown lines, and smile lines,” she explains. “It helps to inhibit the repetitive motion that causes those rhytides and ultimately softens their appearance.”

Linder recommends using a product containing Acetyl hexapeptide-8 on a BID basis. If used per physician’s instructions, the peptide subtly slows down the muscle contraction and over time diminishes the appearance of fine lines. Acetyl hexapeptide-8, when used in topical skin care products, works a lot like Botox.

For some patients, a topical application is a more appealing option. However, for deeper lines and wrinkles, Botox typically achieves better results than a topical product, Linder adds.

Some products combine peptides with antioxidants, she continues. When used in conjunction with one another, peptides and antioxidants work together “to grab free radicals that damage the skin, protecting the cells from their breakdown effects and then send signals to skin cells, generating new cell growth.”

However, as with all skin care products and “cures,” Linder reminds patients and medical professionals that they need to be educated on product ingredients as well as the concentration of those ingredients in skin care products. A particular active ingredient may be listed on a product label, but that doesn’t necessarily mean there is a lot of that ingredient in the actual formula.

Before and 1 month after treatment with Palmitoyl tetrapeptide-7 and Palmitoyl oligopeptide serum and with support products.
Before and 3 months after treatment with Axetyl hexapeptide-8 serum and with support products.
Before and 3 months after treatment with Axetyl hexapeptide-8 serum and a Palmitoyl tetrapeptide-7 eye cream with support products.
Before and 6 weeks after treatment with Palmitoyl tetrapeptide-7 and Palmitoyl oligopeptide serum and with support products.

“Medical research on peptides documents results based on a specific concentration of the peptide in any given product or application,” she says. “However, many products might use a smaller concentration of the peptide.” Smaller concentrations diminish expected results, and patient compliance with any skin care product is critical to results.

Other effective peptides recommended by Linder include the following:

  • Palmitoyl pentapeptide-4: stimulates types I and III collagen and fibronectin;
  • Palmitoyl oligopeptide: stimulates multiple dermal fibroblast production and decreases elastase (the enzyme that breaks down elastin);
  • Palmitoyl tetrapeptide-7: DHEA-derived; reduces IL-6 production to reduce inflammation; and,
  • Palmitoyl tripeptide-38: stimulates type I and IV collagen and hyaluronic acid synthesis.

Other ingredients are being studied to evaluate their effectiveness in the prevention and repair of skin damage. For example, Linder has modified certain formulas in her product line (PCA Skin Clinical Care Products) to include caffeine.

“Studies are beginning to show lots of benefits from the use of caffeine in skin care,” she says. “In fact, data suggests that caffeine can actually prevent UV damage in skin cells.”


In addition to skin care protocols and topical products, Linder incorporates a variety of procedures in her skin care practice. Dermabrasion, chemical peels, and laser procedures are all available for patients who need a more aggressive approach to skin repair.

Linder’s practice has seen a shift from more ablative procedures to a lighter touch. Nonablative, Fraxel-based procedures are increasingly common, and her group has seen a favorable impact on long-term results in patients.

“Doing a series of light chemical peels over a specific time frame is a great option for patients,” she says. “[They] have less downtime, less damage to their skin, and using appropriate topical products like peptides can help train new skin cells to produce more collagen on their own.”

Incorporating lighter procedures into her patient offering has also benefited Linder’s practice overall. Patients have less downtime and are more satisfied with the results. PAs and other staff members can perform some of the procedures, so patients have the opportunity to bond with the entire staff as well as with the physician, she says.

“Skin care is a very personal business. The more comfortable a patient is with our entire team, the more we’ll be able to do for them and the happier they will be with the results.”


The terms “organic” and “natural,” when used to describe skin care products, can be very misleading in skin care science, Linder cautions. “No skin care product can ever be ‘all natural,’ ” she says.

For example, “Take Vitamin C and alascorbic acid. One is found in an orange, and one is a lab chemical. But they have exactly the same molecular structure. Most natural ingredients, like titanium dioxide, need to be processed to some degree so that they can be used in a skin care product.”

Skin care products require preservatives to keep them safe for patients and consumers. Many people believe that natural preservatives are better for skin, but the truth is that they just aren’t as effective,
she says. Natural preservatives are commonly used in food, but skin care products have different requirements and, thus, product manufacturers use a different way of compounding preservatives into the overall structure of their skin care offerings.

Linder endorses the use of preservatives in skin care products, and believes that shifts in public opinions and perceptions about preservative safety can be described as “a natural ebb and flow.”

“Public opinion tends to shift to and from certain extremes, but reality is that there are a lot of well-designed skin care products on the market, and companies are responsible in their formulations. In fact, many skin care products use the same preservatives used in food products. If they are safe for ingestion, then topically they don’t pose any harm, either.”


Recent studies have begun to investigate the relevance of stem cells in skin care science, Linder says. Stem cells are intriguing, and with many possible uses in the health care field it is natural for researchers to explore options and test theories. In fact, there is significant cutting-edge research that shows an impact on bone growth and wound healing when skin cells are inserted under the skin, she adds.

However, she cautions about touting stem cells as a possible antiaging remedy. “Stem cells are viable, living cells,” she says. “Putting them in a topical product that sits on a shelf for a month or more isn’t really an option.”

The preservatives and stabilizing ingredients necessary in topical products would effectively kill the stem cells, thereby eliminating their ability to activate any kind of new cell growth.

In general, it is difficult to take much of the data gained in current research on stem cells and extrapolate it to skin care products, Linder says. However, she adds that there is great hope for the future, as stem cells can be used in office procedures to generate cell growth and reverse the signs of aging.


Overall, good skin care and results take time, she notes. Patients will see the best results over several months, even when using the best products and products with the highest concentration of active ingredients.

Generally, immediate results can be seen when skin is hydrated properly, but long-term benefits take time to be visible to the naked eye. “If it works fast, it isn’t necessarily good for your skin,” she cautions.

For example, several skin care products contain an ingredient called DMAE (dimethylaminoethanol), a naturally occurring substance that facilitates the synthesis of a neurotransmitter acetylcholine.

On The Web!

See also "The Greening of Skin Care Products" by Wendy Lewis in the April 2008 issue of PSP.

Products containing DMAE have claimed to diminish fine lines in a matter of hours, and it has been demonstrated that DMAE causes some degree of skin tightening, Linder says.

However, a 2009 study published in the British Journal of Dermatology showed data indicating that the DMAE triggers swelling in cell fibroblasts. The cells swell, and then they die. While short-term results may appear favorable, DMAE ultimately kills the cells that produce collagen, causing significant long-term damage.

“Essentially, doctors have to trust that products will work the way they say they will,” Linder says. “Our patients rely on us to provide quality care and get good results. That’s why understanding the research and being informed about appropriate ingredients is so essential in our industry.”

Schae Kane is a contributing writer to PSP. She can be reached at [email protected]