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Avocados
Guacamole, anyone? According to Paula Simpson, BASc, RNCP, the oil found in avocados works to toughen your skin while also hydrating it. Another perk? "Avocados are full of monounsaturated fatty acids," says Robyn Flipse, MS, RD. "This is the healthiest type of fat for the cardiovascular system because it doesn't promote inflammation."