My favorite time of year is diet season. From Christmas to around FebuMarch, the dieters come out in droves. My thoughts on dieting run from concern to suspicion. The terminology used by dieters, the concepts, and the diet formulas used--as well as the various tools necessary to put those formulas to work, are at first glance more depth than the average dieter might wish to wade into. After all, to really engage in a serious weight loss plan one is required to estimate energy needs balanced with energy expenditure. And that my friends, requires some knowledge and understanding of human metabolism.
Human metabolism is the rate at which we utilize fuel—with fuel being foods we consume containing glucose, protein and fat. The term metabolism is somewhat vague and gets used interchangeably with other more specific terms describing energy needs. In general, humming birds have a very high metabolic rate given their size, and other more slow moving mammals like the sloth, have a much lower energy requirement per unit body mass. What we generally refer to as our “metabolism” is actually a collection of energy considerations involving how active we are, our size, gender and age. Generally, the rate of metabolism (number of kcals used per hour on average) takes into account factors like how much we’ve eaten in the last 12 hours, how active we are and other vague and difficult to estimate notions like the amount of stress we are under, our sleep patterns, our hormonal levels and much more. To estimate the energy needs of an individual, we can’t take into account things such as emotional state, hormonal balance, frequency of meals and a host of other variables that may actually impact energy needs; in place of an exact measure, we use three components that are estimated. Therefore, to estimate daily caloric needs, we divide the overall concept of metabolism into three subcategories to consider:
1. Resting Energy Expenditure (Basal metabolic rate)
2. Thermic Effect of Food (energy cost of digestion and absorption)
3. Daily Physical Activity
Being able to estimate those components of daily living allows us to get a rough estimate of the total daily energy requirements--allowing us to again estimate how many calories to take in to actually lose weight. We can measure directly and indirectly the total energy expenditure but it involves expensive equipment and again, isn’t readily available to the general public. Calculations of energy requirements are available and easy to use, but again, to arrive at an estimate we need to cover the three basic areas of daily energy expenditure.
More Later
No comments:
Post a Comment