2.4: Trial By Calorie
- Page ID
- 56112
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)Our tremendous concern about how fat we are supports a multibillion dollar diet industry. Ironically, the industry prospers in large part because most weight-loss schemes are doomed to fail. In other words, the success of this industry depends on the consistent failure of its products. Let’s look at some simple tests of reality that we can apply to the alluring promises of so many weight-loss schemes.
The number of calories in a pound of body fat is about 3500. Thus, the calculation that a person must take in at least 3,500 extra calories to make a pound of fat. And a person must expend about 3,500 extra calories to use up a pound of body fat.
In terms of food, 3,500 calories represents about 50 slices of bread or some 135 Hershey chocolate kisses. Supposedly, one would have to eat this much extra to gain about a pound of fat. This means that unless drastic and probably unhealthy measures are taken, fat gain or loss isn’t going to be very great within a short period of time. Claims of fast weight-loss are suspect, as is the common fear (or hope) that a person has gained (or lost) several pounds of fat over a weekend.
Common sense tells us that we can’t take 3,500 calories out of our daily diet unless we are eating at least this much food to begin with. Consider again the woman of 5′5′′ who has 25 pounds of excess weight and weighs 150 pounds. Can dieting alone make her lose a pound a day?
In a normal day, she probably eats food providing about 2,300 calories, which without much exercise, her body uses. So even with complete fasting, she can’t lose a pound of fat (3,500 calories) in a day unless she adds significantly to her normal activities. If she ate nothing, creating a resting deficit of 2,300 calories, the remaining 1,200 calorie deficit necessary to meet her goal of 3,500 calories would require exercise equivalent to running about 10 miles a day.
People are often drawn to the various plans, schemes, and nostrums that tout unrealistic notions of easy weight-loss. Such sudden changes in weight are usually due to a gain or loss of body water. Weight that’s lost so easily isn’t fat, and is also easily regained. The dieter is alternately drier and juicier. What’s in fact left are lighter wallets and a heavy sense of failure.
Losing excess fat within a relatively short period of time is hard. No wonder we’d rather not believe that the size of our fat stores is simply a matter of consuming more energy than we expend. To help us face this simple truth, we might begin by reminding ourselves that the ease with which we become fat isn’t a curse upon the human race or a highly visible punishment for gluttony or inactivity. It’s instead an essential evolutionary mechanism for human survival.
