Macronutrients, or macros for short, are carbohydrates, fats, and proteins. So, basically, everything you eat can be broken down into these three macronutrient categories. Alcohol is in a class of it’s own and not considered to be one of the macronutrients.
How much should you be eating of each macro? Depends..
Each macro contributes a certain number of calories per gram.
Carbohydrates and proteins provide 4 calories per gram
Fats provide 9 cal per gram
Alcohol has 7 cal per gram
Step 1- Determine your goal weight loss, muscle gain etc..
Step 2- Calculate your BMR (there are many online calculators)
Step 3- Determine your activity level
Now that you know your daily calories amount to maintain your weight, you can decide how you want the calories to be distributed.
Let’s use the keto diet, since it’s so popular right now!
Most keto diets allow about 100 grams of carbs daily. So if you determined a 2000 calorie per day diet was what you need to achieve your goals, 400 calories would be from carbs. 100 grams x 4 cal/gram= 400 calories
Most keto diets allow 30% of calories from protein. So, 2000 x .3 = 600 calories or 150grams of protein. The remainder of the calories would be from healthy fats. 1000 calories are already used up from the protein and carbs, so that leaves 1000 calories from fat 1000/9 = 111 grams of fat.
Does that make sense? To lose weight you must take in less calories than you use up. Each pound of fat has approximately 3500cal. So, if you want to lose 1 pound of fat per week you need to eat 500 calories per day, less than the amount you calculated from your BMR.