Dr. Sommerville on Antiaging Skin Care


Q. What are growth factors and peptides?

Dr. Sommerville: These substances are short-chain sequences of amino acids. Some of them increase collagen production and decrease breakdown of existing collagen. Others, like neuropeptides, mimic the effects of botulinum toxin and decrease facial muscle contraction, therefore promising to reduce lines and wrinkles. Carrier peptides deliver important trace elements such as copper necessary for wound healing and new blood vessel formation. Other peptides are being studied for hyperpigmentation and dark spots. We still need rigorous clinical trials to determine the clinical efficacy of peptides.

Growth factors regulate cell communication and are essential in wound healing. By repairing micro-wounds in sun-damaged skin, they are potentially effective in reducing photoaging. Growth factors due to their large size have difficulty penetrating the skin. As with peptides, further studies are needed to determine their clinical efficacy.

Q. Are moisturizers necessary, and which ones are most effective?

Dr. Sommerville: As long as we bathe every day and use shower gels that are in essence glorified detergents stripping away the moisturizing sebum from the skin, we will need to moisturize to restore the protective barrier in the skin and reduce transdermal water loss. Dry skin can trigger or exacerbate such conditions as eczema or psoriasis, resulting in inflammation and itching. Some moisturizers offer added benefits by including colloidal oatmeal and oat extracts. Oatmeal was used for skin health and beauty as early as 2000 BC in Arabia and Egypt to soothe and protect dry, itchy, inflamed skin.

Q. What is new in sun protection? What is the best sunblock?

Dr. Sommerville: There is no question in my mind that routine use of sunscreens has been shown to reduce skin cancers and slow the process of aging in the skin. Unfortunately, most sunscreens in the past offered little or no UVA protection. There is conclusive evidence that both UVA and UVB contribute to the development of skin cancer with UVA energy actually contributing more to aging of the skin because of deeper penetration. This is why zinc oxide and titanium dioxide are the gold standards for sun protection since they are broad-spectrum UVA- and UVB- protective. They are also photostable which means that they do not easily degrade upon ultraviolet exposure. Zinc oxide and titanium dioxide work by reflecting UV radiation from the skin. Due to recent technology of reducing the particle size of these products, such sunscreens are cosmetically-elegant, non-gritty, and leave no white residue. There are other broad spectrum sunscreen ingredients on the market. Some of them, when activated by UV radiation, may actually generate harmful free radicals which may be absorbed into the skin. This is why it is important to apply such sunscreens in conjunction with an antioxidant serum.

Q. What SPF should we choose?

Dr. Sommerville: The American Academy of Dermatology generally recommends at least SPF 30. One should keep in mind that the term SPF (Sun Protection Factor) refers only to the UVB protection so look for the term “wide spectrum” on the sunscreen label. Many people do not realize that UVA penetrates car window glass. This is why American drivers look older on the left side of their face while British drivers look older on the right side of their face.

Q. How much sunscreen should we apply to our skin and how often should we reapply it?

Dr. Sommerville: One should apply at least a teaspoon of sunscreen for the face. One should apply 1 ounce (2 tablespoons) of sunscreen per entire body 30 minutes before going outside. Let’s keep in mind that an average sunscreen container contains about 4 oz of sunscreen. Let’s assume that we are on the beach and reapplying the recommended 1 oz of sunscreen to our body every 2 hours, then after a full day, we would have gone through the entire container! The question is, does anyone use this much sunscreen? According to studies we are vastly underusing sunscreens.

The measurement of the sun protection factor (SPF) is the usual method in determining their effectiveness. The declared SPF is based on the application of a large quantity of sunscreen per given area of the body. According to studies, only a quarter of this amount is generally used in real life. Because the relationship between the SPF and the sunscreen quantity is now believed to be exponential, studies indicate that such use in the general population accomplishes an SPF of about 3 even if the actual sunscreen used has an SPF of 81!