Why Macros Matter

As I mentioned in the post called Why does nutrition advice always seem to change?, there always seems to be some nutrition craze that tempts us to change what we eat or how we eat it. It is important to understand the science behind these trends so we know whether they’re worth our attention, or if they are more likely to result in an unnecessary, or even unhealthy, preoccupation with food.

“Counting your macros” is something I have been hearing a lot about lately. The macronutrients–carbohydrates, fat, and protein—are called “macro” because we need large amounts of them in our diet. Micronutrients—vitamins and minerals—are called “micro” because our bodies only require them in small amounts. The deal with macronutrients is that the body uses carbs, fats, and proteins in very different ways—ways that are not interchangeable. Thus, we really do need to eat adequate amounts of each “macro” for our bodies to function properly—physically, mentally, and emotionally. Here’s what these VIP “macros” do for our bodies.

Carbohydrates

Our bodies are designed to run on carbs. They are, by far, the preferred fuel. Once digested, carbohydrates are readily available for energy. Our brains, which account for 20-25% of our total energy expenditure, rely on a steady supply of blood glucose, primarily provided by carbohydrates. In general, about half to two-thirds of our food should be carbohydrate-rich foods such as grains, fruits, vegetables, and legumes. Because different sources of carbs provide varying levels of energy, vitamins, minerals, fiber, and phytochemicals, you really need to vary your carb intake. Cutting out or severely limiting carbs can cause stress on the body as it works overtime to make protein and fat do the job that carbohydrates should be doing. This stress could keep your body from performing at its physical and mental peak.

Protein

It’s easy to understand why people get hung up on protein. The protein we consume provides the building blocks for bones, muscles, cartilage, hair, nails, skin, and blood. Protein also supplies key components for enzymes and hormones, which perform thousands of essential body functions. However, despite popular belief, more is not better. Our bodies get all the protein they need when 25% of our diet consists of protein-rich foods such as meats, dairy, soy, nuts/seeds, and legumes. If our bodies have more protein than they need, they can’t store it, and instead, break it down for energy.

Fat

Fat has long been feared, avoided, and maligned. Truth is—fat is as important and essential for our bodies as protein and carbohydrates. The lining, or membrane, of each of the millions of cells in our bodies is made up primarily of fat. Our brain is 60% fat. Fat is necessary for absorption of vitamins A, D, E, and K, as well as essential components our body cannot make in any other way. Emerging research shows that some types of fats may play a role in helping people deal with depression.

Although macros aren’t something the typical person needs to obsess over if they are eating a healthy diet, we do need to have a balance of fat, protein, and carbohydrates in our usual eating pattern so our bodies function properly. Restriction and overconsumption can both occur as functions of disordered eating. When an eating disorder is present, it’s best to work with your dietitian and health care professionals so you can make sure that you are getting the proper balance of these macronutrients to support your body, mind, mood, and recovery.