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Facts About Metabolism

The Truth About Metabolism
 
Tammy Beasley, RD, CSSD, CEDSN
Rev It Up Fitness, LLC
 
Similar to a specialized race car, our bodies are amazing machines that are designed to run efficiently and consistently when fueled and maintained appropriately. Our “fuel system” can hold about four hours of fuel; therefore, we turn the system (metabolism) ON by consuming breakfast within 1- 1 ½ hours after rising and not allowing more than four hours to pass between the next fuel stop. This fuel stop may be a full meal, or may need to be a small snack (similar to a quick stop at the gas station for a few dollars of gas to “buy time” until you can stop and fill up the tank). If your body does not receive energy on a timely basis, the fuel gauge will indicate “empty” and trigger your body to respond in ways that will conserve energy. Our metabolic rate responds automatically and negatively to the unavailability of adequate calories. Depending on the severity of the restriction – how long between meals on a daily basis, how long this pattern has continued, and how many restrictive weight loss attempts have occurred in the past - our bodies will respond in such a manner as to preserve its life as long as possible.    
 
Your body’s responses to a compromised metabolism include:
1.                 Calorie-burning rate decreases.
2.                 Work output of the heart, per minute, decreases up to 50%.
3.                 Muscle tone and body temperature decrease.
4.                 Blood sugar level declines.
5.                 Hunger is more intense and lasts longer.
6.                 Cravings for foods, specifically fats and sugars, are increased.
7.                 Body fat stores are conserved and protected.
8.                 Fat cells increase their content of lipoprotein lipase (LPL), the fat storing enzyme, making it easer to regain body fat.
9.                 Calories expended during exercise are decreased as an adaptation to less energy available.
10.            Physical performance is compromised.
11.     Obsessional thinking about food and weight increases.
12.     Mental concentration and clarity are compromised.
13.     Moods are altered and often include irritability, anxiety, and
         depression, which in and of itself decreases metabolic rate.
 
But once on/off food restriction of foods has stopped, your metabolism rate will begin to normalize. Your body can begin losing weight again if that is one of your health goals. And your body actually has the ability to use metabolic rate to maintain weight even during periods of overeating, if the excessive intake is not routine, by increasing the rate it burns calories by 10 – 30% to compensate for the energy “splurge”. (More good news!) Your body is an amazing machine – it will work WITH you if you take care of it!