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.
Macadamia nuts have the most saturated fat of all nuts, but 80 percent of their fat content is monounsaturated, which has been shown to lower triglycerides and have beneficial effects on LDL and HDL cholesterol.
When to grab a handful: At breakfast. "They contain fiber, protein, and healthy fats, meaning they will help your breakfast stick with you for longer-lasting energy," says Upton.
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