Macros Part II: The Skinny on Fats

June 16, 2015: 0300 hours

When I say “fat”, it probably conjures multiple images in your mind. They could range from a fat person, to fast food, or “fat free” snacks and foods. For years, we have been told through media, diet books and programs, and even education in school that eating fat is what makes you fat. I’m here to tell you that isn’t true — not entirely. The truth behind fat is far more complex than “eat fat, get fat.”

The three macro-nutrients, protein, fat and carbohydrates, are your body’s way of getting energy from food. You eat a piece of pizza and the protein, fat, and carbs from that pizza are digested and sent to various parts of the body to be used. Protein and carbs both have 4 calories per gram, and fat has 9 calories per gram (McKinley Health Center). This gives us two important insights regarding the dietary intake of fat. First, we know why the “eat fat, get fat” movement started — if you eat a lot of fat, it has more calories per gram than the other macros, you get to watch your waistline expand. But here’s the second insight, with all of that energy jam-packed in each gram of fat, if you eat more fat (and can keep yourself from overdoing it at one sitting), you will feel full and satiated for longer. So should you be eating a high-fat diet? Depends. At resting or low-intensity exercise, defined as less than 50% of your VO2 Max (rule of thumb: if you can maintain conversation while doing the exercise, it’s low-intensity), your body prefers to use fat as it’s fuel. For high-intensity exercises, your body prefers to use carbohydrates (University of Montana). What does this mean as far as what you need to be doing? If your primary exercise is low-intensity, such as walking your dog, then eating a high-carb diet without adequate fat intake can lead to weight gain and can actually screw up your metabolism. If your primary exercise is high-intensity, such as wind-sprints or weight-lifting, then eating a high-fat diet without adequate carbs can lead to substandard training and can actually screw up your metabolism.

You may have noticed nearly back-to-back phrases of “screw up your metabolism.” I’ve got bad news and good news. If you eat the Standard American Diet (SAD), which is highly processed and “fat free” until you go crazy and eat a large pizza yourself, your metabolism is probably already screwed up. Actually, if you eat any diet that doesn’t have adequate carbs and fats, your metabolism is probably screwed up. The ideal metabolism is one that is able to switch from fats to carbs as necessary based on the current activity of the person — until I start sprinting, my body uses fat for fuel; while I’m sprinting, my body switches over to use carbs for the duration of the workout. The problem is that most of our bodies aren’t this efficient because we’ve confused them with our diets for most of our lives. But it’s going to be ok — we can fix it. By eating sources of fat and carbs at the right times throughout the day, we can teach our bodies to use each macro as needed.

Here’s how it looks: I workout at approximately 1600 hours every day, this means that just before and after my workouts, I concentrate my carb intake (this will be expanded on in the carbohydrate post). But it means that the rest of my day, I need to be focusing on getting my energy from good fat sources, animal meats (fish!), nuts, full-fat butter, peanut butter (all the women just breathed a sigh of relief). For those of you who took my advice on tracking your food, 100 grams of fat per day for men is recommended and 70-75g for women. These are obviously baseline numbers, you have to listen to your body. If you are starving all day long, increase your fat and protein intake.

Quick caveat before I wrap up this post — these numbers and the advice I give are based on you treating your body like an athlete. In this profession, we may have to complete physically demanding tasks at a moment’s notice without prior warning. This means that we need to be in top physical condition, because losing is unacceptable for us. Take pride in yourself and be prepared to do whatever is called of you. That means eating and training like an athlete. Workout of the Day:

  • 90 push-ups
  • 90 sit-ups
  • 2 mile run

Quote of the Day: “Battle is the most magnificent competition in which a human being can indulge. It brings out all that is best; it removes all that is base. All men are afraid in battle. The coward is the one who lets his fear overcome his sense of duty. Duty is the essence of manhood.” – General George S. Patton