Macros for Dummies

We break down the mystery of macros and tell you what you need to know about these essential nutrients.

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It seems like all people talk about these days are their macros, as they use some app on their smartphone to calculate whether they can eat the bun that came with their burger. But what exactly does it mean when they say something does or doesn’t fit into their macros? And how do you know what your allotted macros should be? And why is this suddenly so trendy? Read on as we break down the mystery of macros.

Macros Mean What?

“Macro” is an abbreviation for macronutrient — nutrients the body requires in large amounts, such as protein, carbohydrates and fat. These macronutrients, along with the micronutrients (vitamins and minerals) and phytochemicals (plant chemicals) we get from food get broken down through the digestion process into small sub-units such as amino acids, glucose and fatty acids. These then travel through our bloodstream and interact with our cells in various metabolic processes.

All Calories Are Not Created Equal

For a long time, it was generally believed that “a calorie is a calorie” and that body composition was a factor of calories in vs. calories out. But things have changed.

“It’s increasingly understood that the truth is much more complex,” says Jonathan Jordan, a NASM-certified personal trainer and nutrition coach in San Francisco. “It makes logical sense. If I eat 2,000 calories a day from a balanced mix of healthy protein, carbs and fat, I will be healthier and achieve a better body composition than someone who eats 2,000 calories of soda and cake.”

As such, macronutrient-focused meal plans help fine-tune your nutrition, health and results by breaking up your calories based on your body type, genetics, goals and activity level. It’s an advanced nutritional strategy for decreasing body fat, adding muscle or maintaining body composition — you simply determine your ideal grams of protein, carbs and fat to target each day to reach your caloric intake goal to support your body composition goal.

Determining Your Breakdown

Jordan says that the best way to learn your ideal macro numbers would be to meet with a nutritionist or registered dietician. If you don’t have access to a professional, there are several online resources that can help. He recommends MyFitnessPal, a free app that can help users determine and track their caloric and macro goals based on their current and desired weight and goals.

In general, macros are computed first by determining your ideal daily caloric target. This is calculated through a formula based on your current weight and activity level. Once you have that, you then look at your body type (or somatotype) and body composition goals to figure out what percentage of your caloric goal should come from fat, protein and carbs. Then break those percentages down into grams.

“For instance, I am a 180-pound male who exercises seven hours a week and I want to gain muscle,” Jordan says. “I should target 3,600 kcal a day. I’m a mesomorph (naturally muscular and athletic), so I would start at 30 percent protein, 40 percent carbs and 30 percent fat. That breaks down to 270 grams of protein, 360 grams of carbs and 120 grams of fat.”

Tracking Your Meals

If you’re dedicating yourself to a macro eating plan, it’s imperative to use an app to track each meal’s breakdown. “People are generally bad at estimating,” Jordan says. “Research shows that when we attempt to eyeball or estimate our food, we overestimate the good stuff and underestimate the bad stuff — even when we are trying to be spot-on honest. So tracking gives us a sense of accountability and accuracy.”

Jordan says that if you see the results you want, maintain your split. And if not, then you may need to refine it (increase or decrease your calories, switch to a split for a different somatotype, tweak your carbs or fat percentage, etc.). 

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