Sun Myths, Busted: Base Tans, Window UV, and Why It’s Never Too Late to Protect Your Skin
New Zealand’s UV levels are very intense. Peak summer UV Index (UVI) is commonly around 12 and can exceed 13 in the far north. Extreme UVI (11+) is associated with high risk of rapid skin damage. The Ministry for the Environment notes NZ peak summer UV can be around 40% higher than places at similar latitudes in the Northern Hemisphere. That’s why sun safety isn’t just a “beach day” issue—it’s a daily health habit for all of us.
Myth 1: “A base tan is protective.”
A tan is not a healthy glow- it’s your skin’s response to ultraviolet (UV) radiation. When your skin darkens, it’s reacting to DNA damage by producing more melanin—essentially a distress signal, not a shield.
Yes, a tan can slightly reduce how quickly you burn, but that’s not the same as protecting you from harm. It is estimated that a “base tan” equals roughly to SPF 2–4, which is far below what’s recommended for meaningful protection (typically SPF 30+). Base tan can not stop the underlying processes linked to premature ageing of skin and importnatly increased skin cancer risk.
Myth 2: “I don’t need sun protection indoors or near windows.”
This one surprises my patients the most: glass blocks most UVB (the rays that cause classic sunburn), but UVA can pass through standard window glass. UVA penetrates deeper into the skin and is strongly linked with photoageing and long-term skin damage, hence skin cancers.
That’s why people can accumulate sun damage while:
- sitting by a sunny window at home or work
- commuting/driving regularly (especially on the side closest to the window)
Some vehicles offer better UVA protection in specific windows, and UV-protective films/tints can significantly reduce exposure—but don’t assume you’re protected just because you’re behind glass.
Myth 3: “It’s too late to start sun protection.”
It’s never too late! Of course, you can’t erase past sun exposure—but you can reduce future damage and lower your ongoing risk. UV exposure is cumulative, and prevention still matters even if you’ve spent decades without sunscreen.
Starting now helps because:
- you reduce additional UV injury (which adds up year after year)
- you slow visible photoageing (pigmentation, roughness, fine lines)
- you reduce the number of future “high-dose” UV hits that drive risk
What to do instead: Make protection routine, not dramatic: Slip, Slop, Slap and Wrap.
NZ’s high UV environment and significant melanoma burden, early detection matters—if someone is higher risk (fair skin, history of sunburns, lots of outdoor exposure, personal/family history), regular checks are crucial.
Recent Comments