Your Skin Matters at Karen Bowen Dermal Therapist

Chemical versus physical sunscreens – which to choose?

“What’s the difference?” you may ask. Well, sunscreens vary significantly in formulation and action, and this is why.

Chemical sunscreens act by absorbing ultra-violet (UV) light for a limited period following application, after which they themselves are absorbed into the bloodstream … only to be found in the liver 72 hours later. Further, chemical sunscreens absorb UVB rays (responsible for sunburn) but not UVA rays (responsible for photo-ageing, collagen degeneration and some forms of skin cancer).

Physical sunscreens, on the other hand, work by clinging to the surface of the skin to physically reflect all harmful UVA and UVB rays. Thus, they act as a total sunblock, provided they remain in place … and, unlike chemical sunscreens, they’re not absorbed into the bloodstream to later end up in the liver.

Although physical sunscreens are water-resistant, it is generally recommended that they be reapplied every 80 minutes or so, to take into account excessive perspiration and/or incidental activities like rubbing the skin. The general rule with physical sunblocks is: you move it, you lose it!

With chemical suncreens, the sun protection factor (SPF) is a mathematical equation relating to the rate at which they absorb UV rays once applied to the skin. Physical sunscreens cannot be given an SPF; however, the protection they offer is equivalent to that of an SPF 30+ chemical sunscreen.

Finally, by virtue of the ingredients they contain (see below), physical sunscreens have significantly less potential to cause allergenic or irritating reactions than the chemical alternatives.

Remember: protect yourself today to enjoy the benefits of tomorrow — because your skin matters!

Sunscreen ingredients

Chemical sunscreens

  • PABA
  • Octyl methoxycinnamate
  • Axygenzone
  • Butyl methoxydibenzoylmethane
  • Benzophenone

Physical sunscreens

  • Titanium dioxide
  • Zinc oxide
  • Zirconium oxide

Please note: If you’re unable to visit the clinic, please ask one of our friendly staff members to post your products to you.