Nutrition

Macro Tracking 101: Everything You Need to Know to Start

Calories in, calories out — but what about protein, carbs, and fat? This beginner's guide explains macros without the overwhelm.

May 28, 20269 min read

Calories tell you how much you ate. Macros tell you what it was made of. For some goals the second question matters as much as the first.

The three macronutrients

  • Protein — 4 kcal per gram. Builds and repairs tissue, and is the most satiating of the three.
  • Carbohydrate — 4 kcal per gram. Your body's most accessible fuel.
  • Fat — 9 kcal per gram. Hormone production, absorbing vitamins A, D, E and K.
  • Alcohol is a fourth at 7 kcal per gram, contributing energy and nothing else.

    Protein is the one worth getting right

    If you track only one macro, track protein. It is the one most people fall short on, it preserves muscle while you are losing fat, and it keeps you full — which makes a calorie deficit survivable rather than an exercise in willpower.

    A reasonable range is 1.6–2.2 g per kg of body weight if you are training or in a deficit. Below about 1.2 g/kg, people in a deficit tend to lose more lean mass than they intended.

    Carbs and fat are largely a preference

    Once protein is set and calories are set, the split between the remaining two matters much less than the internet suggests. Some people feel better on higher carbohydrate, some on higher fat. Both work.

    Pick the split you can actually sustain. The best diet is overwhelmingly the one you stay on.

    How to start without hating it

  • Week one: change nothing. Log what you already eat. You cannot adjust a baseline you have not measured.
  • Week two: fix protein only. Leave everything else alone.
  • Week three: adjust total calories toward your goal.
  • Changing one variable at a time tells you which change did what.

    Accuracy, honestly

    Food labels are permitted a margin of error, restaurant figures are estimates, and your own weighing is imperfect. Tracking is accurate to roughly ±10% at best.

    That is fine. You are looking for a trend across weeks, not a precise daily figure. Chasing exactness is how tracking turns into something unpleasant that you quit.

    When to stop

    Tracking is a teaching tool, not a life sentence. Most people need a few months to learn what portions look like, then can eat by eye and check in occasionally. If it starts to feel compulsive rather than useful, that is the signal to stop — and worth talking to a professional about.

    Put this into practice

    Mealio builds the plan, the grocery list and the nutrition maths for you.

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