As a trainer I often get questions about nutrition. Today I got one that I thought would make for a good blog post, as nutrition is often unnecessarily complicated. "What do you think about macros"? The smart ass response was, "I don't". When I dug a bit deeper the client was really asking how important I thought tracking individual macro-nutrients were and specifically how important carbohydrate consumption was. Apparently the individual had come across someone in the fitness world who was a big proponent of tracking macros and pushing large amounts of carbohydrates.
Macro-nutrients are the large nutrients which make up all of the calories that we consume on a daily basis. They consist of protein, fat, carbohydrates (this includes fiber), and alcohol (hopefully to a very small degree). For simplicity sake a gram of protein and carbohydrate consist of 4 calories, a gram of fat is about 9 calories, and a gram of alcohol is around 7 calories. Fiber is basically undigested, so typically is not counted toward calorie totals. Each nutrient is metabolized, stored, and used differently in the human body. So while calorie consumption/expenditure is ultimately the driving force for weight loss or gain, the macro-nutrient consumption of those calories can impact how we feel, perform, sleep, recover, and the composition of our body (how much fat and muscle we have).
Unfortunately, this all can be overly complicated and cause people to feel paralyzed about how/what they should eat. The reality is that outside of highly competitive athletes, or individuals putting in significantly more that 60 minutes of intense exercise more than 4 days per week it likely doesn't make a big difference. The two numbers I would recommend individuals pay attention to is protein intake, and caloric intake. Other than that trying to consume a minimum of 5 servings of fruits/veggies each day, and striving to eat mostly whole minimally processed foods and you'll likely feel, look, and perform great. Protein intake should be between 0.72-1g/lb of target body weight. Calories can vary considerably based on your activity level and goals, but most general fitness clients (not trying to gain significant amount of weight) will likely fall in the 10-15 calories per pound of target body weight. If you have ambitious muscle growth goals, or are very active then you may need more. Again carbohydrate intake and fat intake can very wildly. But for general fitness clients I think it should be based on preference more than anything. Carbohydrates and fat should make up your remaining calories, with carbohydrates being at 100g per day or more (unless you are following a ketogenic diet), and fat should make up at least 15% of total calories. See the chart below to give you an idea of the broad ranges that could work for a given individual. If weight is your primary concern then calories should be your primary focus. If you are concerned with body composition then protein should play a very close second in degree of importance. Carbs and fats should simply fall in the listed ranges based on lifestyle and preference, unless you have lofty performance goals or are putting in large amounts of intense training each week.