Forget shakes, herbs, and high-tech energy boosters: The single best supplement for a guy's diet is a handful of nuts. Besides being known for helping fuel athletes through long days of climbing and skiing, nuts can help fight obesity and high blood pressure when added as a snack to a healthy diet. Recent studies have shown that nuts can decrease rates of heart disease and cancer and even extend life expectancy. But don't just reach for the peanut bowl: There's a science behind which nuts to eat and when to eat them.
Hazelnuts are high in fiber, with three grams per ounce. Fiber helps keep you full by slowing down food digestion and absorbing water in the stomach, which tricks your body into believing you've eaten more than you have. Copper, a key mineral for producing red blood cells and maintaining healthy bones and nerves, is abundant in hazelnuts. You can eat them whole as you would any other nut, but don't buy them blanched or peeled – the light-brown skin that covers hazelnuts contains the most antioxidants.
How to eat them: Make your own Nutella by grinding 1 cup roasted hazelnuts in a food processor until a paste forms, about 5 minutes. Add 1/4 cup cocoa powder, 1/4 cup honey, 1 tbsp olive oil, 1 tbsp vanilla extract, and 1/4 tsp salt; blend 1 minute. Spread on toast, or use to top ice cream.
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