The term “metabolism” is talking about a lot these days.
You may know that if your metabolism is too slow, then you are more likely to gain weight. But what exactly does this all mean?
“Metabolism” is the word used to describe all the biochemical reactions in your body. It’s how you take in nutrients and oxygen and use them to fuel everything you do.
Your body has an incredible ability to grow, heal, and generally stay alive. And without this amazing biochemistry you would not be possible.
- activities you can control (e.g. physical activity, etc.)
- activities you can’t control (e.g. heart beat, wound healing, digestion, etc.)
- storage of excess energy for later
When you put all of these processes together into your metabolism you can imagine that these processes can work too quickly, too slowly, or just right. The speed of your metabolism is referred to as the “metabolic rate”.
This is how fast your metabolism works and is measured in calories.
The calories you eat can go to one of three places:
– Work (i.e. exercise and other activity)
– Heat (i.e. from all those biochemical reactions)
– Storage (i.e. extra leftover “unburned” calories stored as fat)
As you can imagine the more calories you burn as work or creating heat the easier it is to lose weight and keep it off because there will be fewer “leftover” calories to store for later.
There are a couple of different ways to measure metabolic rate. One is the “basal metabolic rate” (BMR) which is how much energy your body uses when you’re not being physically active.
The other is the “total daily energy expenditure” (TDEE) which measures both the resting metabolic rate as well as the energy used for “work” (e.g. exercise) throughout a 24-hour period. This includes your basal metabolic rate, calories burned with physical activity, and the thermic effect of food.
Your basal metabolic rate accounts for approximately 70% of your daily calories burned, so maintaining a healthy metabolism is really important in terms of losing weight or staying lean.
What affects your metabolic rate?
The first thing you may think of is your thyroid gland. This gland at the front of your throat releases hormones to tell your body to “speed up” your metabolism. Of course, the more thyroid hormone there is, the faster things will work and the more calories you’ll burn.
But that’s not the only thing that affects your metabolic rate.
Your other hormones also have a huge impact on your metabolism. Hormones such as the adrenal hormones (Cortisol and DHEA), Insulin, and your sex hormones (Estrogen, Testosterone, Progesterone) all have play important roles in a healthy or unhealthy metabolism.
Your size also matters!
Larger people have higher metabolic rates; but your body composition is crucial!
As you can imagine, muscles that actively move and do work need more energy than fat does. The more lean muscle mass you have the more energy your body will burn and the higher your metabolic rate will be, even when you’re not working out.
This is exactly why weight training is often recommended as a part of a weight loss program. You want those muscles to be burning those calories for you at work and at rest.
When people lose weight, their metabolic rate often slows down which you don’t want to happen. You help to offset this by maintaining your muscle mass.
Aerobic exercise also temporarily increases your metabolic rate as your muscles are burning fuel to keep your body moving.
The type of food you eat also affects your metabolic rate!
Your body actually burns calories to absorb, digest, and metabolize your food. This is called the “thermic effect of food” (TEF).
You can use it to your advantage when you understand how your body metabolizes foods differently.
Fats, for example increase your TEF by 0-3%; carbs increase it by 5-10%, and protein increases it by 15-30%. By trading some of your fat or carbs for lean protein you can slightly increase your metabolic rate.
Another bonus of protein is that your muscles need it to grow. By working them out and feeding them what they need they will help you to lose weight and keep it off.
And don’t forget the mind-body connection. There is plenty of research that shows the influence that things like stress and sleep have on the metabolic rate.
This is just the tip of the iceberg when it comes to metabolism and how so many different things can work to increase (or decrease) your metabolic rate.
Recipe: Lemon Herb Roasted Chicken Breasts
2 lemons, sliced
1 tablespoon rosemary
1 tablespoon thyme
2 cloves garlic, thinly sliced
4 chicken breasts (boneless, skinless)
dash salt & pepper
1 tablespoon extra virgin olive oil
Preheat oven to 425F. Layer ½ of the lemon slices on the bottom of a baking dish. Sprinkle with ½ of the herbs and ½ of the sliced garlic.
Place the chicken breasts on top and sprinkle salt & pepper. Place remaining lemon, herbs and garlic on top of the chicken. Drizzle with olive oil. Cover with a lid.
Bake for 45 minutes until chicken is cooked through. If you want the chicken to be a bit more “roasty” then remove the lid and broil for another few minutes (watching carefully not to burn it).
Serve & enjoy!
Tip: You can add a leftover sliced chicken breast to your salad for lunch the next day!