Dermatologist and skincare expert Dr Stefanie Williams answers all your SPF questions - plus the best SPF for acne-prone and sensitive skin

All your sun cream and SPF questions, answered

positive

What is the difference between UVB and UVA rays?

How do chemical and physical sun creams work differently?

How much sun cream should I use and how often should I reapply?

Does a foundation or moisturiser with SPF offer full protection?

What are the most common mistakes people make with SPF?

How do I find a sunscreen that won’t block my pores or give me spots?

How long does sunscreen last once it’s opened?

What is the best SPF to use so I can tan without burning? 

Check out our favourite SPF products below

Your expert cheat sheet to staying safe in the sun 