Macros Explained: How Much Protein, Carbs and Fat You Need

Before you start

This book has one job: to make the numbers behind your food boring. Not exciting, not moral, not something to argue about online. Boring, useful, and small enough to keep in your head while you stand in a shop holding two packets.

The first three chapters are the theory, and they are short. Everything after is the practical half: how to log a real life, how to read a label in ten seconds, how to order in a restaurant, and what to do when there is no scale anywhere near you.

Every chapter ends with a box naming the exact screen in ORO that does that job for you. Some of the scanning and AI tools are part of ORO Premium. Nothing in the method depends on them, they only make it faster.

Calories decide your weight, macros decide what it is made of

Two people can eat the same 2,000 calories a day and finish the month looking completely different. Calories set the direction. Macros set what the change is made of.

Start with the unglamorous part. Your body runs on energy, energy is measured in calories, and over time the balance between what you take in and what you use decides which way your weight moves. No food is magic enough to escape that and none is bad enough to break it on its own. That one sentence is the entire reason a calorie target exists.

But weight is not one substance. What sits on the scale is muscle, fat, water, stored carbohydrate with water attached to it, and the food currently inside you. A month where you lose three kilos of fat and a month where you lose two of fat and one of muscle look identical on the scale and nothing alike in the mirror. Macros are how you steer which month you get.

What a macro actually is

Macronutrients are the three things in food that carry energy: protein, carbohydrate and fat. Everything you eat is some mix of them. Alcohol carries energy too, which is why it counts even though it builds nothing.

Standard reference values used across public nutrition databases.

Fat carries more than twice what the same weight of protein or carbohydrate does. That is not a moral fact about fat, it is a density fact: a spoonful of olive oil is good food and expensive food at once, and the unmeasured spoonfuls that went into the pan are the most common reason a careful day does not add up.

The order of operations

Almost every nutrition argument you have seen is people fighting about step four while ignoring step one. The order is fixed:

• Calories decide the direction your weight moves.
• Protein decides how much of that change is muscle and how much is fat.
• Carbs and fat split what is left, arranged around your training and what you enjoy eating.
• Meal timing and supplements come last, and move the needle far less than the internet suggests.

Food quality is not a separate rule, it works through that list: whole foods make protein easier to hit and hunger easier to manage. But an unmeasured healthy diet is still an unmeasured diet. The rest of this book is only about making the first two lines easy on an ordinary Tuesday.

Protein, carbs and fat: how much of each

Only one of the three is worth being strict about. Once you know which, this chapter gets much shorter than you expected.

Protein is the one. It is the raw material your body repairs and builds muscle with, the most filling of the three per calorie, and the most expensive to digest. In a calorie deficit it is the difference between losing fat and losing whatever your body reaches for first. Hitting protein changes your outcome. Hitting a particular carb number mostly changes your afternoon.

The protein number

Widely cited sports nutrition guidance, including the International Society of Sports Nutrition position stand, puts daily protein for people who train at roughly 1.6 to 2.2 grams per kilogram of bodyweight, about 0.7 to 1.0 grams per pound. Sit at the higher end while losing weight, when protein is protecting the most. Individual needs vary, and if you have a kidney condition or follow a medically prescribed diet, that range is a conversation for your doctor or dietitian.

General guidance based on the 1.6 to 2.2 g/kg range, rounded for everyday use. If you carry a lot of excess weight, using a target bodyweight rather than your current one keeps the number sensible. Not a medical prescription.

Fat is not optional, carbs are flexible

Fat does real work: hormone production, absorbing vitamins A, D, E and K, and making food worth eating. General guidance keeps it near 0.6 to 1.0 grams per kilogram, and rarely below about twenty percent of daily calories for long. Push it lower and you get a diet that is technically correct and practically unbearable, which matters, because unbearable diets end.

Whatever calories remain after protein and fat belong to carbohydrate. That is the whole rule. Carbs are training fuel, so train hard and often and you want more of the remainder here. There is no threshold above which they become fattening. Fibre is the part worth watching, around 25 to 30 grams a day in general public health guidance, because fibre is what makes a large plate of food feel like one.

An illustration of the method, not a plan to copy. Your own target depends on your stats, activity and goal.

Hit your calories and your protein and the exact split of the rest matters far less than anyone selling a ratio wants you to believe. So choose the split you will still be eating in March. Sticking with it is a real variable, and the one most people ignore.

Setting targets you can trust

A target you cannot explain is a target you abandon the first week it feels hard. Here is exactly where yours comes from, in three steps.

Step one is your resting metabolism, what your body burns doing nothing at all, and the majority of your daily total. It is estimated from your height, weight, age and sex with a published equation. ORO uses Mifflin-St Jeor, or Katch-McArdle when you have entered a body fat percentage, because knowing your lean mass makes the estimate better.

Step two is your activity. That resting number is multiplied by a factor for how much you actually move, running from about 1.2 for a genuinely sedentary life to about 1.9 for someone with a physical job who also trains. Those two steps give your maintenance estimate: the calories where your weight stays put.

Step three is the adjustment for your goal, and this is the step people wreck.

General guidance, not a medical target. Rates of change vary widely between individuals, and a very low intake should only be undertaken with professional supervision.

Why the aggressive version loses

Doubling the deficit does not double the fat loss. It reliably doubles the hunger, takes more of your muscle along with the fat, makes every session worse, and raises the odds that week five is the week you stop. A moderate deficit held for twelve weeks beats an extreme one held for nine days, and it is not close.

The biggest source of error is not the equation, it is the activity multiplier, and most people pick the flattering option. If you are honestly between two levels, take the lower one and let your own results argue you upward, which they will do quickly if you were wrong.

Treat the first number as a hypothesis

Every equation here is a population average applied to one specific person, so it will be a little wrong for you. The formula gets you to the right neighbourhood in thirty seconds. Three or four weeks of your own logs find the exact address, which is Chapter 8. And keep one rule for life: do not accept a health number from a source that will not tell you where it came from.

Logging without obsession

The aim is not a perfect diary. It is a diary you are still keeping in six months, which means every meal has to cost seconds rather than minutes.

One fact makes this easy: most people eat a rotation of roughly twenty to thirty foods, over and over, for years. Your diary looks daunting on day one and repetitive by day ten. The first week is typing, every week after should be tapping, and if you are still searching for the same yoghurt in month two, the app is being used wrong.

Five ways to stop typing

• Recent and Frequent. Your last foods and your most used foods, already listed. This alone covers most breakfasts forever.
• Saved meals. Log a combination once, name it, and it becomes one tap. Six of these usually cover a whole week.
• Recipes. Build what you actually cook once, say how many servings it makes, then log by the serving.
• Copy. Same lunch as yesterday? Copy it across instead of rebuilding it.
• Duplicate a day. The meal prep button. Cook Sunday, eat the same three days, copy the whole day forward in two taps.

Then there is quick entry, for the moment you already know the calories from a menu board or a label and have no intention of searching a database. Type the number, name it if you like, done. A rough entry logged in five seconds beats a perfect entry you never make, because the diary with a hole in it is the one people abandon.

The rules that keep this sane

• Log as you go. Memory at 11pm is fiction, and always flattering fiction.
• Log the bad day too. It is not a confession, it is the most useful data in your week.
• Estimate rather than skip. A blank teaches you nothing, a guess teaches you something.
• Read the week, not every meal. One review beats six anxious checks a day.

When to stop tracking

Logging is a tool, and a tool that starts to hurt should be put down. If tracking makes you anxious, if you avoid meals with other people so the numbers stay tidy, if one number can ruin your day, or if the rules keep getting stricter on their own, stop logging and speak to a doctor or a registered dietitian. There are good ways to eat well that involve no numbers at all, and no result is worth your relationship with food.

Reading any label in 10 seconds

You do not need to read a label. You need three things off it, and you can have all three before you have finished putting your basket down.

One: the serving size, before anything else. This is where labels mislead without technically lying. The tidy numbers on the front are per serving, and the serving is whatever the manufacturer decided, often two thirds of what a normal person pours. Check whether you are reading per 100 grams, per serving or per pack, then multiply by what you will truly eat.

Two: protein per portion. You know your daily target from Chapter 2, so one number tells you whether this product helps you get there or only spends your calories.

Three: the first three ingredients. Ingredients are listed by weight, heaviest first, so the first three are most of what is in the packet. If sugar or an oil shows up there in something you thought was savoury or lean, you have learned everything you needed.

The ORO Score, and what it is not

Scan a product and ORO grades it from 1 to 10, with a short list of what is good and a short list of watch-outs. The grade is not an AI opinion. It is computed by ORO's own rules engine from the product's nutrition facts and ingredient list, built on three published frameworks: the Nutri-Score nutrient profile, the NOVA classification for level of processing, and public EFSA and IARC positions on additives. Same product, same grade, every time, with the reasons shown to you rather than hidden.

Now the limits. A score compares products, it does not judge you, and it is not a health claim about any individual food. A high scoring food eaten in quantity still puts you over your calories, and a low scoring one inside a well built week is genuinely fine. Use the grade to choose between two things on the same shelf. That is what it is for.

Barcodes for anything in a packet

For anything with a barcode, skip the reading. Scanning pulls the nutrition from public food databases and fills the macros for you, so a packaged lunch is logged in about four seconds. Not every barcode is in those databases, especially supermarket own brands, and when one is missing you can search by name or type the macros from the label you are already holding.

Eating out without derailing

Restaurants are not the problem. Walking in with no plan and deciding at the exact moment you are hungriest is the problem.

There are only two versions of this. Either the place publishes its nutrition information, which most large chains do, or it does not, which is every good local restaurant in the world. Both have a solution, and neither requires you to order a dry salad while everyone else eats.

Chains: decide before you arrive

For chains the numbers already exist, so the only skill is looking at them early. Choosing on your sofa is a completely different decision from choosing at the table with a queue behind you. Pick the dish in advance, then spend the meal talking to the people you came with instead of calculating.

Everywhere else: photograph the menu

For everywhere else, ORO Menu handles the thing with no good manual solution. You photograph the menu, one photo per page, and ORO reads every dish on it and ranks them against what you have left in your day.

It is worth knowing what happens there, because two systems are involved and only one is AI. The calories and macros per dish are an AI estimate read from the menu text, anchored to standard reference values for comparable prepared foods and to typical restaurant portions. The ranking is not AI: ORO's own rules engine compares each dish against the calories and protein you have left today, your goal, your diet style and your allergies, using the targets from Chapter 3.

Because kitchens vary enormously, every dish is shown as a range rather than an exact number and the less confident estimates are labelled. One hard limit deserves saying plainly: a menu can never confirm allergens. If you have an allergy, ask the restaurant, every time.

Four things that work at any table

• Anchor the meal on a protein and choose the rest around it. Grilled or roasted over fried, as a default rather than a rule.
• Sauces and dressings on the side. The highest leverage sentence you can say to a waiter.
• Drinks count. Cocktails, juices and a second glass of wine are often the largest single item of the evening and the easiest to forget.
• One big meal does not matter. A restaurant dinner inside a normal week is noise, which is what the next chapter is about.

When you cannot weigh it

A kitchen scale is the accurate way. It is not the only way, and it is never the way at somebody else's dinner table.

Two things are true at once. Weighing is the most accurate method available to you, and refusing to log anything you cannot weigh is how people end up with three good days and four blank ones. The blank days damage your reading of the week far more than an imperfect estimate ever will.

Your hand is a portion guide you always have

• A palm of meat or fish is roughly a protein portion, in the region of 20 to 30 grams of protein.
• A cupped hand is roughly a portion of cooked rice, pasta, oats or potato.
• A thumb is roughly a portion of a fat: oil, butter, nut butter, cheese.
• A fist is roughly a portion of vegetables, and you can be generous here.

A general portion guide for estimating, not a measurement. Hand size scales roughly with body size, which is the small piece of cleverness that makes it work.

Or photograph the plate

When the plate is in front of you and no scale is in sight, take a photo and let ORO estimate. It identifies the food, estimates the macros, shows an ingredient by ingredient breakdown and a confidence level, and then waits. It never saves anything by itself. You adjust what looks wrong, which matters, because you are the one who knows there were two eggs and not three. Estimates get noticeably better with a short hint, like chicken thigh, sweet potato, cooked in olive oil, since the cooking fat and the cut of meat are exactly what a photo cannot show. This feature is part of ORO Premium.

Consistency beats precision

Here is the freeing part. Your logged number is an estimate no matter what you do. Labels carry legal tolerances, a medium apple is not a fixed object, and a restaurant portion is whatever the cook felt like serving. Perfect accuracy was never available.

What you need instead is a consistent method. Estimate the same way every day and your week to week comparison stays honest even when individual numbers are off, because the trend still tells the truth. So weigh the things carrying the most calories and the most error, which are oils, nuts, nut butters, rice, oats and meat, and estimate the rest with a clear conscience.

Trust the trend, not the day

Your bodyweight can swing more in one day than it genuinely changes in a month. Read the daily number as a verdict and you will quit over something that never happened.

Overnight, the scale responds to salt, to how many carbohydrates you ate (each gram your body stores holds water alongside it), to whether last night's meal has finished its journey, to sleep, to hormonal cycles, and to the temporary inflammation of a hard session. None of that is fat. All of it shows up in the morning as a number that feels like a judgement.

An illustrative month. The day to day swing is about 0.9 kg (2 lb). The real change across the whole month is 0.5 kg (1 lb). The noise is bigger than the signal, which is why a single morning cannot be read.

On some mornings in week four this person weighs more than on some mornings in week one, while unambiguously heading the right way. Judging themselves on Thursday of week two, they would have concluded the whole thing was broken and eaten accordingly.

How to weigh, and how to read it

Weigh under the same conditions, most mornings, after the bathroom and before food or drink. Then ignore each number and only look at the seven day average. Weighing daily and reading weekly gives a smoother, more honest line than weighing once a week, because a single weekly reading is one roll of the same dice.

Apply the same logic to food. Nobody hits the target precisely and nobody needs to. Compare your seven day calorie average to your target, not Tuesday to your target. A day four hundred over, inside a week that averages on target, is an uneventful day.

Let your own data correct the formula

After a few weeks of logging, something better than any equation appears: your own results. ORO compares what you actually ate against what your weight actually did, works out what your maintenance really looks like, and offers to update your targets. That is your data beating a population average, which is the right way round. As for changing something yourself, give it three weeks. If the seven day average has gone the wrong way for three weeks running and your logging was honest, adjust. Anything faster is reacting to weather.

Training-day eating and the eat-back toggle

Should you eat more on the days you train? Usually a little. The trap is eating back a burn number that was never accurate to begin with.

The case is simple. Hard sessions run largely on stored carbohydrate, and a session you fuelled is a session you performed in, which over months is the difference between progressing and merely attending. Training days also have more room in the budget for those carbs.

The simplest version that works: keep protein flat every day, because your recovery does not know what day it is, then move some carbohydrate from rest days into training days. The weekly total is unchanged, the hard days feel better, and you have added no new rule to remember.

Why burn estimates deserve suspicion

Every calories burned figure you have seen is an estimate, including a good one. ORO estimates training burn with the ACSM metabolic equation and MET values from the 2011 Compendium of Physical Activities, a defensible published method that still varies from person to person. Wrist devices are frequently generous.

This matters because of one arithmetic trap. If you told the intake quiz you train four times a week, your activity multiplier already counted that training once. Adding the full burn from every session counts it twice, and a phantom four hundred calories a day quietly cancels a well built deficit.

What the toggle actually does

That is why the eat-back setting exists and why it is deliberately conservative. Turn it on and, when you log a workout, a small cautious share of the estimated burn is added to that day's food budget. A share, not the whole thing, precisely because of the double counting above.

• Turn it on if your sessions are long or genuinely hard, you set your activity level honestly low, and you are hungry or losing weight faster than intended.
• Leave it off if your activity level already assumed your training, or if you would rather hit one steady daily number and not think about it again.

Around the session itself: carbohydrate and some protein in the few hours before, protein in the meal after. Beyond that, timing is mostly noise, since total daily protein matters considerably more than the window you eat it in. If you train early and cannot face food first, training fasted is fine and the meal afterwards does the work.

Feature index

Every ORO feature this guide used, and where to find it.

Volume I is the four week on-ramp if you are starting from zero. Volume III covers getting stronger, which is what protects the muscle this book keeps talking about. Volume IV is for the week it all falls apart, which is a normal week and worth planning for.