To understand how retinol helps reduce blemishes, it is important to understand how acne formation is triggered in the first place. Skin’s pores contain oil glands, which are responsible for producing oil to lubricate the skin and hair. Usually, oil glands produce the right amount of sebum or oil, but they can be overactive at times, resulting in excess sebum production. The combination of excess oil and dead skin cells can cause pores to become clogged, creating the perfect condition for P.acnes bacteria – a bacteria that can contribute to the formation of acne – to become trapped and multiply.
Topical retinol formulations increase cell turnover in skin, ultimately reducing the buildup of dead skin cells. With fewer dead skin cells present on the surface of the skin, it becomes more difficult for pores to clog. Retinol creams work via chemical exfoliation, which may be less abrasive than mechanical exfoliation that involves the use of scrubs.
However, as with any topical skincare products targeting acne, results may take time. It is important that retinol and any other blemish-fighting products are applied as recommended by your skincare professional. It is also essential that a 
broad spectrum sunscreen 
is applied daily when using a retinol. Look for non comedogenic, oil free sunscreen formulations that deliver high UVA/UVB protection without clogging pores.