Safari Books Online is a digital library providing on-demand subscription access to thousands of learning resources.
People apply a number of criteria when they seek food, including convenience, palatability (“It tastes good”), and cultural habit (“Mom always made me a PB&J for lunch, so that’s what I’m going to make myself”). I’m going to add a fourth one: eating for fitness. This is a fitness book after all, and food is at least 50 percent of the game.
Our bodies have tens of trillions of cells, and millions of them turn over every day, even every second (your body makes millions of new red blood cells each day alone; the whole kit and caboodle of them turns over every four months!). In other words, you’re constantly growing new parts of your body, specifically at the cellular level. Many of the ingredients for new cells, such as the fatty acids for cell membranes and the amino acids for new proteins (that go into everything, including the membranes), have to come from the foods you eat.