Do redheads have greater sagging and skin laxity?

Great question.
Genetics play a major role in the aging process, especially in the quality of skin we have. You should google the Fitzpatrick Scale for skin types, which will give you an idea of which skin is more prone to sun damage,  for example red heads are a Fitz. 1,   Meaning they hardly ever tan and always burn in response to the Sun. Which means if you need to protect your skin from sun damage in order to long term skin laxity and sun damage. Although genetics is important, you can help your skin by avoiding environmental hazards like UV radiation, smoking, excessive alcohol, adequate hydration, and a good diet. 
The best skin types that are more protective from the environment are the olive skin tones, Mediterranean, and African Americans.  

Hope that helps,
Dr Kamran Dastoury,MD

Great question! People with
red hair do tend to have thinner skin which is more susceptible to sun burn and
also wrinkles. This is because redheads have less of the pigment, eumelanin,
which gives the skin and hair a brownish hue and offers protection from sun
damage, which in turn can cause more wrinkles.