without catching fire. There are a specific number of calories that
strike the earth each day in the form of sunlight. Calories are not
found in food. They are only related to food insofar as food has the
potential to be measured as a form of energy.
Can Food Calories Be Accurately Measured?
Hundreds of Internet website post lists of foods and calories. The
U.S. Department of Agriculture publishes a searchable online data-
base (http://www.nal.usda.gov/fnic/foodcomp/search/) with calorie
information on thousands of food.
Is the information provided by the USDA and other websites accurate?
Unfortunately, the answer is both yes and no. Yes, there are solid
scientific studies using real foods and real laboratory conditions to
support the specific calorie numbers that appear in the USDA data-
base and in other published lists of food and calories. This research
can be very high quality, sophisticated, and scientifically sound. But
it is research based on laboratory analysis—not research based on
the passage of real food through a person’s digestive tract. Unless
food gets digested, it cannot provide us with any calories (energy).
When food calories are measured in a lab, a device called a bomb
calorimeter is used. This device measures energy in the form of heat.
Within this device, a highly oxygenated, sealed chamber contain-
ing a food sample is floated in water. An electrical current is used
to ignite the food-oxygen mixture, and as it burns, the water sur-
roundingthe floating chamber heats up. The number of calories in
the food is determined by the change in water temperature. A high-
calorie food gets the water hotter by releasing more heat energy
than a low-calorie one.
The human body, of course, is not nearly as simple as a lab device.
We don’t digest food by setting it on fire. We digest chemically, and
our biochemistry is highly individual—in fact, unique. The calories
of energy we obtain (or don’t obtain) from food can vary significantly,
and some individuals are better matched to one kind of food versus
Healthy Weight Loss — Without Dieting