The Danger: Though lake swimming presents less threat than salt water or chlorine, the sun remains a major issue. Think of your hair like you might fabric: if you leave a rug outside, you'll notice that the color fades. The sun dehydrates pigments sapping hair of shine and vibrancy, which is especially bad for redheads, brunettes, and anyone with lowlights.
The Tip: People say they always wear hats, but are they really? Also, if your hat has all those little holes in it, then you're only getting so much filter. Wear a cute scarf under that straw hat, and you'll great protection. Or stick to skinny dipping at night, when you're truly safe from sun!
The Product: We pay such close attention to our skin, applying SPF religiously. We should incorporate sunscreen for our hair, too. An open hair cuticle is like an exit for your color, so protect it! Brand new from Kerastase is its Huile Celeste ($39) protective oil mist with UVA and UVB protection to be sprayed on before and during sun exposure. For after sun, Masque UV Defense Active ($60) and other Soleil products are designed for "sun-exposed" hair.