Skin Cancer

How much sun is too much?

At Dee Why Skin we are often asked how much sun is too much. Sometimes sunburnt people come to visit us for a skin check. And that includes people who’ve had two or three melanomas! We are clearly not getting the message through. This Latest News post will try to redress that. A little bit of knowledge about UV can save you a lot of grief.

The sun is both good and bad for us. Too much sun and we get skin cancer. Too little and we lack Vitamin D and have weak bones. Sure, you can take Vitamin D pills, but nothing beats the phytochemicals that our bodies make when exposed to natural sunlight. There is a fine balance between too little and too much sun, and this is how to achieve that balance.

How much sun exposure do we need?

UV radiation from the sun varies with time of year, time of day, how much and what sort of cloud cover, pollution, altitude and other factors. UVB is the specific type of UV radiation that makes the most Vitamin D. UVB is at its strongest when the sun is overhead, 1pm in a Sydney summer and noon in winter.

The following advice applies to healthy fair-skinned people. Those with dark skin and those who cover their skin for any reason are at greater risk of Vitamin D deficiency. If you’ve had lots of skin cancers, talk to your doctor.

In a Sydney summer, when the UV Index is above 3, you will get all the Vitamin D you need with just a few unprotected minutes here and there in the sun. I try to get 5 or 6 minutes at 1pm in just a pair of shorts. More than that and you risk skin cancer. And don’t be fooled by cloudy and cold days. You can still get burned. You can find the current UV Index at the bottom of every page of this website.

In a Sydney winter, you should spend more unprotected time in the sun than you do in summer. A 20-minute walk at midday is great. Swimming and gardening in the sun are other physical activities that help increase Vitamin D.

What if I’ve reached my minimum sun exposure?

Once you’ve achieved the minimum amount of sun exposure on any one day, more UV is damaging. Any kind of sunburn, even a light pink, means you’ve had way too much UV. If the current UV Index (bottom of this page) is above 3, you need protection. Click BOM to find out even more information on UV radiation.

The best ways of protecting yourself from too much UV are:

  • Avoid sun exposure in the middle of the day. Go out early or late to avoid UV damage. Seek shade.
  • Wear protective clothing when outdoors – broad-brimmed hats, long-sleeved shirts, long pants or skirts, and wrap-around Category 3 sunglasses. Wear gloves if you’ve had skin cancers on your hands.
  • Sunscreen SPF 50+ should be applied to all unprotected, dry clean skin 20 minutes before sun exposure, then every 2 hours. You’ll get good protection with 5mL (1 teaspoon) to each arm, leg, torso front, torso back and face (including neck and ears). That’s a total of 35mL (approximately 7 teaspoons) for full protection.

I want to know more!

A couple of valuable Cancer Council articles …

To find more information on the benefits and risks of UV radiation, click here.

To find out all about sunscreen, click here.

4 Comments

  1. Hi Dr Barnes, Thanks for your post. The specifics about sun exposure and the amount of sunscreen to use were a wake up call for me. I have a question about sun damage from reflection. I often skip sunscreen in the face when I’m walking because I wear a wide brimmed hat. I have ‘heard’ recently that reflection from ground and side surfaces can also cause sun damage; hence the need for sunscreen even with a hat. What’s your view on that? Thanks again

    1. Great question! You’re absolutely right, Roger. Reflection off the ground, sky, clothes, surfaces, all cause UV damage. You need a broad brim hat and SPF 50+ cream for full protection.

    1. Thanks for your comment, Shela. I try to be fastidious with matters of importance like this. Being careful in the sun can make the difference between living and dying, literally.

Leave a Reply

Your email address will not be published. Required fields are marked *