I start my summer out by gradually building my base, so that my skin gets used to the sun and doesn't burn. Ten to twenty minutes a day is sufficient.
The best way to avoid sunburn in the summer is to significantly reduce or eliminate all together your sugar intake, toxic foods, drinks and drink lots of high quality water. Gradually build up exposure time depending on how sensitive your skin is to the sun. Use an organic sunscreen without out parabens and other harsh chemicals - http://www.ewg.org/2010sunscreen/.
If you plan to be at the beach all day or are going to be in intense sun all day, I recommend Badgers. Another great natural alternative to sunscreen, which I've tried myself, is organic unrefined coconut oil or real Shea butter. These actually act as sunscreen and protect your skin from the harmful rays of the sun. The bottom line is that we need sun exposure coupled with a healthy fat intake in order to absorb vitamin D. Consider how healthy you are from the inside out instead of the outside in.
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