Study SPF for Summer Sun

While sipping margaritas by the pool this summer, we should be thinking about how well we’re protecting our skin from the harmful effects of the sun. There are two types of rays: UVA and UVB. UVA penetrates through clouds and glass. These are the rays used in tanning beds. UVB is the sunburning ray—and the chief culprit for hyperpigmentation. Both rays cause skin cancers, premature aging and even eye damage (cataracts).

The best protection against these rays is to avoid the sun entirely. However, since that’s near impossible to do in the summer, the next best solution is to wear SPF (sun protection factor) for the skin, and clothing that has UPF (ultraviolet protection factor).

The biggest misconception of SPF is that the larger the factor, the stronger the protection. Actually, the factor indicates how long, not how strong. Take the factor and multiple this by your burn time, and that is how long it can be worn before needing to reapply—with the exception of swimming or perspiring at a rapid pace. For example, if your burn time is 10 minutes and you are wearing SPF 30, you will have 300 minutes before needing to reapply.

There are two types of SPF: physical and chemical. Titanium dioxide and zinc oxide are both physical (natural). They are photostable (won’t break down with exposure to heat or sun), they start working immediately and are considered Broad Spectrum, since they protect from both UVA and UVB rays. Physical factors max out at 30. Chemical SPFs require a wait time of 20 minutes before exposure to sun, they are unstable unless a filter is added and may be irritating to the skin. Most common are avonbenzone, octinoxate and octocryline. Chemical factors will tend to be higher than 30.

How much should we use? On the face, use ¼ teaspoon; on the neck, use ¼ teaspoon for front and back; ½ teaspoon on each arm; and 1 teaspoon per leg. When in doubt, use a lot.

Gina “Gigi” Gianforti is an esthetician, nail tech, instructor and owner of Gigi70 Natural Skin Care. Connect with her at 520-390-0081 or

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