9781422269916

When you exercise, your muscle fibers develop little tears, and your body uses protein to patch them back up.

Fat Fat is the most energy-dense macronutrient, with around 9 calories per gram. Fat comes from, well, fat—butter, oils from plants like coconuts or olives, meat, and even certain fruits and seeds, like walnuts and avocados. Fat is useful because it insulates our nerves—without fat, electrical impulses would misfire and not travel to their intended destination. Our organs are cushioned by fat, and it insulates our bodies. Despite the negative press fat gets, it’s essential to proper bodily functioning. Not all fats are created equal, though, and there are many different types. Saturated fats, like coconut oil, butter, and lard,

Chapter 1: Food, Energy, and Your Body

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