Skin Encyclopedia

An evidence-based skincare reference by SYNC Beauty.

Encyclopedia

How Often Should I Reapply Sunscreen?

sunscreen is generally reapplied about every two hours during sun exposure, and more often after swimming, sweating heavily, or towel drying. Reapplication matters because the protective film breaks down and...

How Often Should I Reapply Sunscreen?

sunscreen is generally reapplied about every two hours during sun exposure, and more often after swimming, sweating heavily, or towel drying. Reapplication matters because the protective film breaks down and...

How Much Sunscreen Should I Use on My Face?

the commonly cited amount for the face is roughly a quarter to a third of a teaspoon, often described as two finger-lengths of product. Using too little is one of...

How Much Sunscreen Should I Use on My Face?

the commonly cited amount for the face is roughly a quarter to a third of a teaspoon, often described as two finger-lengths of product. Using too little is one of...

Do I Apply Moisturizer to Damp or Dry Skin?

applying moisturizer to slightly damp skin is generally recommended, as the leftover surface water gives humectant ingredients extra moisture to bind and helps occlusives seal it in. Patting skin until...

Do I Apply Moisturizer to Damp or Dry Skin?

applying moisturizer to slightly damp skin is generally recommended, as the leftover surface water gives humectant ingredients extra moisture to bind and helps occlusives seal it in. Patting skin until...

Does Non-Comedogenic Guarantee No Breakouts?

the belief that a 'non-comedogenic' label ensures a product won't clog pores or cause acne, which it does not guarantee. The term is not standardized or regulated, and because skin...

Does Non-Comedogenic Guarantee No Breakouts?

the belief that a 'non-comedogenic' label ensures a product won't clog pores or cause acne, which it does not guarantee. The term is not standardized or regulated, and because skin...

Is Hypoallergenic a Regulated Term?

the assumption that 'hypoallergenic' is a legally defined, tested standard, which in many regions it is not. In markets like the United States, the term is not regulated by authorities...

Is Hypoallergenic a Regulated Term?

the assumption that 'hypoallergenic' is a legally defined, tested standard, which in many regions it is not. In markets like the United States, the term is not regulated by authorities...

Can Sunscreen Cause Vitamin D Deficiency?

the concern that wearing sunscreen blocks enough UV to cause vitamin D deficiency, which real-world evidence largely does not support. While sunscreen reduces UVB exposure in theory, studies show typical...

Can Sunscreen Cause Vitamin D Deficiency?

the concern that wearing sunscreen blocks enough UV to cause vitamin D deficiency, which real-world evidence largely does not support. While sunscreen reduces UVB exposure in theory, studies show typical...