Sometimes Conventional Wisdom is Not All That Wise

Food facts controlBack in 1958 Dr. Max Wishofsky developed what came to be known as Wishofsky’s Rule, which states that 3500 calories equals one pound of body weight.  In other words, if you want to lose one pound of weight you need to burn 3500 more calories than you consume.

This made for simple math.  For instance, if you ate 500 fewer calories than you burned every day for a week (seven days) then you would lose one pound of body weight (7 days x 500 calories/day=3500, or one pound of weight loss).

This rule is basically universal.  It’s cited in over 35,000 websites as well as in textbooks, scientific articles, and expert guidelines (including from the US Surgeon General).

Here’s the only problem…The Wishofsky 3500 Calorie Rule doesn’t work.  In fact, it seems to only be about half right.

The reason is pretty simple.  The research tools and data we have available today are vastly different than they were over 50 years ago.  The 3500 calorie rule does not take into account age, height, weight, body composition, and physical activity.  As it turns out, weight loss is REALLY complicated.  There is no such thing as one size fits all.

Something called metabolic adaptation appears to play a big role in weight loss.  In essence, as you lose weight your basal metabolic rate changes…meaning you don’t need as many calories every day “just to exist.”  As you lose more weight the calories needed to maintain your weight also goes down.  The result is that weight loss is rarely “linear” it’s actually “curvilinear.”  This means that most individuals entering a weight loss program tend to lose more weight in the first few weeks than they do as time goes on.  Over time, additional weight loss becomes more challenging.

(I know, if you’re looking to lose weight this is not the kind of news you’re wanting to hear but my goal is to give you the truth…not to provide false promise.)

This new concept of weight loss is known as the Dynamic Model.  Much of the research has been done by Dr. D.M. Thomas at Montclair State University (full disclosure: Dr. Martin is a colleague of my colleague and good friend, Dr. Tim Church, the Chief Medical Officer of ACAP Health).

There are now free, downloadable applications of the Dynamic Model, housed in Microsoft Excel and Java platforms available at:

If you enter your baseline age, height, gender, weight, duration of the intervention, and target caloric intake the app will provide you with dynamic predictions of weekly weight change.  I should warn you this is a free, research tool so don’t expect some slick website with all sorts of bells and whistles.  It’s pretty basic but it will provide you with realistic expectations based on solid, credible science.

For those of you “geeky” enough about these things, like myself, you can read more in the International Journal of Obesity (2013) 37, 1611-163, which you can access for free at:

Once there, click on “Archive by Issue” then Dec 2013.  Then scroll down to the “Short Communications” section and click on the article:

Can a weight loss of one pound a week be achieved with a 3500-kcal deficit?

Since we now have close to 70% of Americans either overweight or obese it would be great if there were a simple solution for weight loss.  Obviously that is not the case.  However, by arming yourself with the latest credible, scientific research you can at least increase your odds of success.  Please be sure to enjoy the journey.

Stay well,