Nicole Kidman says the key to her youthfulness is strict sun avoidance. And using a day cream that offers protection against ultraviolet light should be an almost compulsory part of everyone's skincare routine.
Outside of the summer months, it's mainly UVA from which we need protecting – A being mainly responsible for ageing (but also capable of contributing to our cancer risk).
Buying a moisturiser containing SPF, however, will only protect you against UVB – the 'burning ray'. So check the label to see if the SPF is broad spectrum or comes with a star rating, which means it offers some protection against UVA, too.