Please have a read of this article by Dr. Diana Howard on the dermal institute site.

Wrinkles, altered pigmentation, loss of skin tone… we all associate these changes with skin aging. Age-related skin changes are the result of genetically programmed changes (intrinsic factors) and environmental wear-and-tear on the skin (extrinsic factors). While both influence the skin’s structure and function, extrinsic factors cause more pronounced changes.

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