The following Mark's Daily Apple article was written by Marksissons and is narrated by Brock Armstrong.

The definitive guide to the primal eating plan. Do the math. In my recent context of calories post, I explained

how the different macronutrients we eat at each meal, fats, proteins, and carbohydrates,

have different effects in the body. I suggested that despite their raw calorie values,

it's far more important to get a lasting, intuitive

sense of how much of each macronutrient you need and when you need it, or not.

But how do you do that? How do you figure out the proper number of calories and breakdown of

fat, protein, and carbs to accomplish your fitness and health goals, to lose weight,

lose fat, gain muscle, maintain status quo, or run marathons. In fact, most popular daily

diets look at overall calories as the main factor in weight loss and weight gain. The age-old conversation of energy's conventional wisdom says that a calorie is a calorie.

From there, most diet gurus generally prescribe some formulaic one-size-fits-all breakdown of fats,

proteins, and carbs. A classically trained registered dietitian will tell you

that protein should be around 10 to 15% of calories, carbs should be about 60%, and mostly from whole

grains, and fat under 30%. This macronutrient breakdown stays the same regardless of how much weight you need to lose

or what other goals you might have.

Barry Sears has his 40-30-30 zone diet.

The USDA bases everything off a choice of between 2,000 and 2,500 calories per day.

But as I said earlier, it's not that simple. Calories do have context.

The human body uses these macronutrients for a variety of different functions, and some of which

are simply to provide energy immediately or well into the future.

Moreover, with regards to energy conservation or expenditure,

the body acts as both an efficient fuel storage depot and as a toxic waste site,

...