How Much Do Macros Really Matter For Weight Loss?

“Low-fat”. “Fat free”. “High-protein”. “Protein-sparing”. “Carbo-loading”. “Carb-free”. If you had ten dollars for every fad diet plan and weight loss product ever promoted to have either a high or low amount of any macronutrient, you could probably pay off the combined student loan debt of Texas and New York combined.

The media’s chaotically clumsy dance with dietary details is well over a decade old. Health is a hot topic that just keeps getting hotter. A cover story titled “Diet Hype: How the media collides with science”, run by Newsweek in 2006, reported its findings that about twenty percent of the headlining Newsweek stories in 2005 were written on health-based topics.

It’s safe to say that the demand for nutrition knowledge is as high as ever, and the attempted supply for that demand has gone far past the point of saturation. Just 20 minutes clicking through Google for a straight answer on what any one macronutrient means for weight loss can leave you 20 brand new questions to ask, and for each of those new questions, you’ll have hundreds of people ready to give you their definitive answers without a single cited source to be seen.

Between all of the different advertisers and fitness gurus singing the praises of their latest and greatest weight loss product, how do you sort between the scientific truth and the snake oil?

Let’s start by breaking each of these macronutrients down to their basic building blocks.


The diversity of different carbohydrate types is a big part of why they’re so easy to demonize.

Sugary snacks made up of simple carbohydrates are commonly presented as evidence to back up the claim of carbohydrates being the “main culprits” of the obesity epidemic, usually with a reference to their insulin-spiking effect if eaten in excess.

The charge against simple carbohydrates is usually made without also citing the benefits of complex carbohydrates in vegetables and whole grains. Complex carbohydrates such as leafy green vegetables, fresh fruit and beans have a high nutrient density level that is especially vital for anyone looking to lose weight healthily and sustain that weight loss.


Despite the popular implication that carbohydrates have an antagonistic relationship with protein, carbohydrates are actually useful for sparing more of the protein that you can actually use. Carbohydrates in your muscles and liver are your body’s main fuel source during the highest levels of physical activity.

Without sufficient carbohydrate stores, your muscle contraction quality, central nervous system health, and overall exercise performance will suffer; this will make it almost impossible to maintain the levels of activity you’ll need to realistically achieve your weight loss goals.


Protein gets heavily promoted as a “panacea” for every kind of health benefit that you could imagine, and it’s safe to say that calling some of these claims gigantic overstatements would be an understatement.

Despite how dramatically its powers tend to be exaggerated, protein still plays a very important role in muscular growth, soft tissue quality, and your overall state of health.

Protein provides essential amino acids that the body cannot produce on its own but still needs to grow and sustain itself without skeletal muscle loss.


Animal-based proteins (meat, dairy and eggs) provide each of the essential amino acids on their own, making them complete proteins. Plant-based proteins such as beans and rice, with only a portion of all the essential amino acids, are called incomplete proteins. Despite being incomplete on their own, beans and rice can be combined to form a complete protein as a team.

If you’re on a highly active weight loss campaign, proper protein intake will be important to help you recover properly for consistent performance quality and health.



As a macronutrient, fats are possibly even more misunderstood as than carbohydrates. The confusion starts when dietary fat is treated as though it’s the same thing as body fat.

Failure to understand the difference between fat as a noun and fat as an adjective leads many people to ask why they should be eating more of something that they’re trying to lose; a perfectly understandable question based in a simple misunderstanding.

In addition to the confusion about how it’s defined as a word, false claims about fat also come from the same type of misunderstanding there is about carbohydrates: a failure to see the difference between the helpful forms of the macronutrient and its unhelpful forms.

Dietary fats are also called lipids, and the lipid family is made up of sterols (such as cholesterol), phospholipids, triglycerides and fatty acids. Most of the fat that we get from butter and meat is in the form of triglycerides.


Fatty acids that are packed with all of the hydrogen that they can hold are what we know as saturated fat. Processed foods are full of saturated fat because they’re packed with hydrogen in the production process, making them firmer at room temperature and easier to store for long periods of time.

Fatty acids that haven’t been completely packed with hydrogen are called unsaturated fats. Unsaturated fats with just a single hydrogen-free spot in their carbon chain are called monounsaturated fats, while those with more free spots are called polyunsaturated fats.

While too much saturated fat from things like fried chicken and donuts can cause all kinds of health issues, monounsaturated fats (olive oil, canola oil, peanuts) and polyunsaturated fats (vegetable oils, mackerel, flaxseeds) can be extremely helpful key players for vital organ protection, energy storage, and fat-soluble vitamin intake.

Getting the right amount of unsaturated fats can be incredibly useful for weight loss success because of the satiety that they create. A stronger feeling of satiety keeps you feeling fuller for a longer period of time after meals, making it much easier to maintain a low-calorie diet without succumbing to cravings.

Ironically, dieters who discriminate against all forms of dietary fat just to lose body fat are actually sabotaging their fat loss potential.

Macronutrient Energy Stores and Recommendations

Aside from the differences in where they come from and how they’re used, carbohydrates, proteins and fats can all be simply described as energy-yielding nutrients. Carbohydrates and protein contain 4 calories per gram, while fat contains 9 per gram. The average person has about 1,500 calories from stored carbohydrates and 100,000 calories from stored fats.

For over 70 years, experts with the National Academy of Sciences (NAS) have come together to create an Acceptable Macronutrient Distribution Range (AMDR) based on Dietary Reference Intakes (DRIs).

Currently, the AMDR for adults is 10 to 35 percent protein, 20 to 35 percent fat, and 45 to 65 percent carbohydrates. Any daily calorie intake of any size, whether it’s 800 calories or 4000 calories, can have the same overall macronutrient proportions.


Changing macronutrient proportions alone won’t cause any difference in weight loss or weight gain at the same overall intake, but proper macronutrient balance is still extremely important for the body’s quality of recovery, energy storage, performance, muscle development, and vital organ health.

Managing the Myths

Even though the low-carbohydrate, high-protein diet gospel pushed by Atkins has drawn a massive following, a search for hard evidence to support it will leave you empty-handed.

In 2003, the New England Journal of Medicine published findings from a one-year study held to check for any possible significant differences between a low-carbohydrate, high-protein, high-fat diet and a low-calorie, high-carbohydrate and high-fat diet.

While the low-carbohydrate group showed a 4% greater amount of weight loss in the first 6 months, there was no significant difference at all after a year had passed.

Not only is there no scientific agreement on any kind of macronutrient-targeting diet being better or worse for weight loss than any other, but there is also no single type of macronutrient-targeting diet that can be guaranteed to cause the same weight change even in people who follow it identically.

Based on your personal metabolism, your rate of weight loss and weight gain compared to another person with the same body weight, activity level, calorie intake and macronutrient proportions could still potentially be completely different.

However, a difference in the rate of either weight loss or weight gain isn’t the same thing as a difference in the direction of the numbers on the scale. If two equally heavy people are both eating at the same caloric deficit and exercising with the same intensity, they’re both going to be losing weight at their own rates, no matter what the macronutrient content of their diet actually is.


Is a low-carbohydrate, high-protein diet typically better for weight loss than diets with a heaver carbohydrate load?

It potentially can be, if your activity level is sufficient enough for a negative net calorie intake by the end of the day; however, that negative net intake is not just because of the fact that there were less carbohydrates in your diet.

In 2003, the Journal of the American Medicine Association published findings that greater weight loss from carbohydrate-restricting diets are due to a lower net caloric intake, not the lower carbohydrate levels. We still have to think of personal choices in meal frequency and the nutrient density of what’s actually eaten.

Not only has there been no strong evidence for low carbohydrate intake alone being a cause for greater weight loss, but studies have actually shown strong evidence for diets higher in whole grains being attributed to lower body mass index. Again, this is just matter of loose association and averages, not the absolutely declarative fact that plenty of low-carb diet plan sellers would prefer you to believe.

A high-carbohydrate diet with a low overall caloric intake will result in more weight loss than a low-carbohydrate diet with a high net caloric intake. The key is to avoid confusing macronutrient density with the overall caloric load of what you’re consuming in total.

If you’re looking to lose weight, you’re doing yourself a major disservice by only focusing on limiting or favoring a specific macronutrient. What’s equally important is the nutritional value of your food choices and carefully monitoring your overall caloric intake to make sure that it actually stays at a deficit.

Whatever your weight loss goal is, aiming to to decrease your overall calorie intake while proportionally maintaining a healthy carbohydrate/protein/fat balance at the lower intake level will lead to much more sustainable results than just spiking up or cutting down on any one macronutrient.


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