This article has been Fact-Checked by Kendall Kennedy MS, RD, RYT
Low carb, low fat, high protein, and the list of diets continues. It can get a little confusing. What is the best weight loss carb protein fat ratio?
There is are plenty of opinions about what ratio of macronutrients is the best for weight loss.
Macronutrients are the nutrients your body needs in larger amounts to stay alive and healthy: carbohydrates, protein and fat. They provide you with the energy to keep yourself moving.
The ratio means what macros make up what amount of your daily calories. Each individual macronutrient also has its up and downsides for weight loss.
How does macronutrient ratio matter?
In theory it’s possible to lose weight with any macronutrient ratio as long as you have a calorie deficit. That does not mean that it’s smart or healthy to do so. Different ratios will have different advantages and disadvantages.
Some ratios will help you feel less hungry. Others can improve your metabolism, the amount of calories you burn. It’s ridiculous to say that the source of calories doesn’t matter in a weight loss frame.
The first thing you need to know is that humans need a certain amount of protein and fats.
No matter what ratio you want to follow, make sure you have at least 0.36 grams of protein per pound of body weight (+-0.8 grams / kg of body weight).
The ideal amount of protein changes with age and activity levels.
The effectiveness of plant-based protein and animal protein vary so eating both sources can be smart.
In terms of fat you want at least 20%, preferably more than 30% of your calories coming from fat.
Differences between carbs, protein and fat for weight loss
Within the 3 macronutrient categories there are also important differences. Not all fats, carbohydrates and proteins are the same.
This adds another different dimension of complexity to the story. 2 people could eat the same ratio of macronutrients but because of healthier choices one of the two could see a lot more weight loss results and be a lot healthier. In general you want to eat a wide variety of whole foods to get different nutrients.
The main focus of this article are the macronutrient groups but the differences within have to be briefly discussed.
Carbs
In general, carbohydrates are good for providing you with short-term energy for high intensity movement. This is a great advantage for athletes in high intensity sports but not so much for people trying to lose weight.
Most carbohydrate sources are a lot less filling than their protein and fat counterparts compared to the amount of calories these foods contain.
All foods raise a hormone called insulin but food with carbohydrates even more so. Bad carbs even more than good carbs. If you eat too many refined carbohydrates your insulin levels can stay permanently elevated.
Insulin can make it harder for your body to burn fat which is not something you want if you’re looking to burn body fat. Higher insulin levels while losing weight can potentially lead to more muscle loss. Muscle helps you burn more calories day in day out on top of other health benefits. You don’t want to lose muscle if you’re looking to lose weight and get healthier.
Bad vs good carbs
Carbohydrates can go from pure white sugar (“bad carbs”) to more healthy carbs like whole grains (“good carbs”). Fiber is also a carbohydrate in theory but because of its unique properties it deserves a separate category when we’re talking about losing weight.
The healthiest carbohydrates can be helpful for weight loss. However, even carbs like rice can add up calories without that many nutrients fairly fast.
If you’re trying to lose weight it can be helpful to avoid confusion and just stay away from most carbohydrate-heavy sources. For most people this alone is enough to lose a good amount of weight. You do have to make sure that you still get enough vitamins and minerals from other food sources.
If you do decide to eat carbs certainly try to avoid the more simple carbohydrates like sugar and refined grain. These don’t fill you up that much while adding a lot of calories to your diet.
Best time of the day to eat carbs
Raised insulin levels are associated with worse health.
Interestingly enough your body is better able to deal with carbohydrates earlier in the day. A carb-heavy food consumed in the morning raises insulin levels than that same food in the evening.
On example of how insulin can be bad for your health is by disturbing the production of certain sleep hormones. Sleep is important for weight loss and good health in general. Another reason to keep carbohydrates for earlier in the day.
Protein
Protein is generally the most helpful macronutrient category for weight loss.
Protein and fat are good at helping you feel full. Hunger and cravings are a big reason people fail to stick to their weight loss habits so it’s good to be able to avoid these.
Your body uses energy, calories, to turn food into usable nutrients. A calorie amount of protein takes more calories to process than that same amount of calories in fat or carbohydrates. You are basically slightly increasing the amount of calories you burn by choosing protein calories over other macros.
Protein can also help you build and preserve muscle. Muscle is very handy when it comes to weight loss. It helps you burn more calories 24/7. That’s why weight lifting is such an effective weight loss exercise.
The only downside of protein is that too much of it can possibly have negative consequences for your health. For most people this is more something to pay attention to if all your other healthy habits are perfect.
If you are at risk for kidney failure you don’t want to overdo it with protein.
Fat
Fats are also more filling than carbohydrates. Like protein this makes it harder to overeat on fatty foods. This is very helpful for losing weight.
The differences within the fat category are pretty interesting. You have saturated, monounsaturated, trans and polyunsaturated fats. And even within those you have different kinds with known different weight loss and health consequences.
Trans fats are definitely something you want to stay away from. The case on the other kinds of fat is not completely clear.
For optimal weight loss and health it’s smart to focus on healthy fat sources like avocados, olive oil, nuts, fatty fish,…
The right carb protein fat ratio for weight loss
So, what should your weight loss carb, protein and fat ratio be?
Most people don’t like to hear it but the answer is that there is no one answer, you have to find out what carb protein fat ratio works best for you personally (besides the minimum healthy requirements of protein and fat).
When you primarily eat whole foods, you will automatically feel fuller with less calories due to the extra fiber intake. After that it becomes a question of being able to stick to your diet plan.
If you can’t live without your banana in the morning, a low carb diet might be a recipe for disaster. If you can’t go without your bacon in the morning, a low fat, low protein diet might not be your thing.
In terms of weight loss, claiming there is one golden carb, fat and protein ratio is not the way to go. You need to find a combination that helps you feel full enough, helps you achieve a calorie deficit and helps you with sticking to your eating habits for the long-term.
Even if you don’t pay attention to adherence there are conflicting studies on what is the best macronutrient ratio (1, 2, 3, 4).
Maybe even more important to pay attention to
Fiber is a helpful nutrient for weight loss.
It has multiple benefits. First of all, fiber feeds your microbiome, the microbes that live in your intestines. The health of your microbiome influences your body’s health and weight. Feeding it well is usually not a bad idea.
Fiber also helps you feel less hungry without adding a lot of calories to your diet. The foods with a lot of fiber also usually contain good amounts of vitamins and minerals.
How to calculate your carb protein fat ratio
The first step to find out your macronutrient ratio is calculating how many calories you need a day to maintain weight. You can still eat too many or too few calories even if your consumption is in the right macronutrient ratio.
A way to get a rough estimate of how many calories per day you need to maintain weight is to fill in the most important variables into a formula. One of the more commonly used formulas is the “Mifflin – St Jeor Formula”.
Here is how you can calculate how many calories you need per day to maintain weight:
Men:
Imperial: (4.536 × weight in pounds) + (15.88 × height in inches) − (5 × age) + 5
Metric: 10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) + 5
Women:
Imperial: (4.536 × weight in pounds) + (15.88 × height in inches) − (5 × age) − 161
Metric: 10 x weight (kg) + 6.25 x height (cm) – 5 x age (y) – 161
Again, keep in mind that this is an estimate. The only way to know for sure is implementing this goal and seeing what the results are like.
Once you have that you can decide on how fast you want to lose weight. In general a healthy weight loss rate is a calorie deficit up to 500 calories a day.
Calories per gram of macro
Now you have your daily calorie count you can decide the percentages each macro will be.
The most common way to measure the energy in food is with calories. The thing is that 1 gram of fat is not 1 calorie.
Here are the amount of calories each macro contains per gram:
- Carbohydrates: 4 calories per gram
- Protein: 4 calories per gram
- Fat: 9 calories per gram
Once you know these things you can start your macro counting journey.
