The widely referenced 2,000 calorie-a-day diet for adults is not a reliable benchmark for weight control, professionals in the field say.
Everyone has different caloric needs because people are different by way of genetics, age, gender, body size, muscle mass and energy expenditure, said Sue Kohlhardt, a registered nurse, nutritional coach and certified personal trainer in Durango.
Kohlhardt likes to establish a clients resting metabolism rate as a starting point. Metabolism is the process by which the body converts nutrients to energy.
The resting metabolism rate, or RMR, tells how many calories are required to keep brain, heart, lungs and other organs functioning if a person did nothing else. Kohlhardt then calculates how many more calories are needed to support a clients daily activities and exercise regimen.
In general, its 25 to 35 percent more than the RMR, Kohlhardt said.
Laura Shelton, assistant vice president at Alpine Bank, has been working with Kohlhardt since February.
Shedding the pounds that accumulated from a sedentary job and the birth of her son two years ago was easy at first.
She knocked off 50 pounds and 23 total body inches (torso and appendages), but had reached a point of diminishing returns.
I was starving myself on 1,100 calories a day, Shelton said. But the pounds werent coming off as fast anymore.
So Kohlhardt had Shelton nose clamped shut breathe through the mouth into an instrument called an indirect calorimeter for 10 minutes to determine her oxygen consumption.
The readout showed that her resting metabolism rate is 1,680.
In order to continue losing weight, Shelton can eat more calories than her resting metabolism rate but fewer than the 25 to 35 percent activity quotient, Kohlhardt said.
Cardiologist Dr. Bruce Andrea uses a metabolism cart, an advanced calorimeter, at his practices Durango Performance Center and Performance Cardiology.
The objective of measuring the resting metabolism rate is to better understand the number of calories we burn, Andrea said. We also can see what percent of calories come from carbohydrates and what percent from fats.
Mikel Love from Peak Wellness & Nutrition said a resting metabolism rate isnt an absolute.
But an RMR gives you a baseline to follow, Love said.
Love determines a clients basic metabolism through bioelectrical impedance, which involves passing an imperceptible electrical current through the body. The results include percent of body fat, percent of lean mass and basal metabolic rate.
Marge Morris, director of the Diabetes and Nutrition Therapy Center at Mercy Regional Medical Center, said maintaining weight and wellness isnt simply a matter of calories in, calories out.
There are many factors involved, Morris said. One fascinating new area involves macronutrients fats, protein and carbohydrates and how they affect health.
Were just beginning to learn more about this research, she said.