Popping a daily multivitamin every day isn't enough for a healthy, well-rounded diet (despite the fact that it's called 'multi'). Nutritionists say the best way to give your body what it needs is by eating nutrient-rich foods. But that doesn't mean you have to eat a truckload of salad every day. Instead, just add these eight superfoods to your usual meals. They'll help rev up your metabolism, slow the aging process, and give you healthier skin.