THE ENEMY WITHIN. THE GLOBAL
OBESITY EPIDEMIC .
Dr. René Menguy
PART 9 MORE ABOUT CALORIES AND HOW TO DETERMINE YOUR BODY’S CALORIC NEEDS.
Earlier, I defined the concept of energy and explained how food’s potential energy is oxidized (burned) by reacting with oxygen to provide us with the energy needed to fuel all our vital functions. The HEAT released by the burning of food keeps us warm. The process, called THERMOGENESIS, accounts for approximately 45% of our average energy expenditures and is essential to life because we are homeothermic animals. Our body temperatures MUST remain within a narrow range. Animals, like snakes, whose body temperatures are determined by the environment are called heterothermic
During the last century the energy content of foods was measured by burning them in an apparatus called a calorimeter and measuring the heat released, a process similar to the values obtained for industrial heat measurement: BTU.
A calorie is the amount of heat needed to raise the temperature of 1 ml (cc) of water by 1 degree Celsius (centigrade). Calories in food are measured in Kilocalories (one thousand calories) and are expressed as Calories with a capital C.
How much energy do our bodies need to function?
AT REST, the body like an idling engine, never stops. The energy used under these conditions, the Basal Metabolic Rate (BMR), defined as the least energy the body requires to fuel all its energy needs during the waking state, i.e. the maintenance of body temperature, breathing and cardiac activity, etc. It is measured by determining the individual’s oxygen consumption under strict conditions. Doctors often order a BMR for someone suspected of having an overactive Thyroid gland. You can measure your own BMR with a fair degree of accuracy by using Harris-Benedict equations
66.5 + (13.75 x W ) + (5.003 x H) – (6.775 x A) = BMR
6.55 + (9.5663 x W) + (1.85 x H) – (4.676 x A) = BMR
W=actual weight in Kilograms; H= height in centimeters; A= age in years
1 Kilogram=2.2046; 2.54 centimeters=1 inch
In most individuals the BMR ranges from 50 to 80 Calories/hour, and in sedentary individuals accounts for 50% to 60% of daily energy expenditures.
Another measure of the body’s energy consumption, the Resting Metabolic Rate (RMR), is defined as the sum of all the body’s energy needs during the waking state, at rest after a meal, with the only physical activity being the fidgeting associated with reading or watching TV. The slight movements, called fidgeting, burn a large number of Calories. Mayo Clinic researchers found that lean individuals moved more while fidgeting than overweight people and burned 350 more Calories a day. .
The BMR or the RMR, like the fuel consumption of an idling engine, can’t be controlled because it is “set at the factory”. Obviously, an engine with a high idle rate uses more fuel than one idling slowly. It’s the same for humans. Each has an individual BMR, a set-point we can’t control. Those with a higher one burn more calories at rest and are usually lean. Those with a lower one burn fewer calories at rest and gain weight more readily than the former.
Exercise enables us to vary our bodies’ energy consumption, as do certain conditions and situations:
BODY STRUCTURE. Muscle uses more energy than fat. The more body fat, the lower the BMR.
AGE. Due to reduced physical activity the BMR decreases with age. After 40, fat replaces 25% of our body’s muscle very ten years; which reduces the BMR by 2% to 3%. Since people eat the same as they age, weight gain is inevitable, a process fitness training can prevent.
ENVIRONMENT. Tropical climes stress the cardio-vascular system’s job of maintaining a normal body temperature. The result: a higher BMR than for those living in temperate climates.
ILLNESSES. Induce the body to burn fat and release energy to fight them. The result: a rise in the BMR, fever and weight loss. This is why our bodies require adequate fat reserves. The excessive thinness pursued by some is very unhealthy.
DRUGS. Can raise the BMR and cause weight loss. At one time, Amphetamines were used for this purpose, a practice now prohibited
HORMONES. Thyroxine secreted by the Thyroid gland stimulates metabolism and, in excess, causes the BMR to rise markedly along with weight loss and other signs and symptoms, a conditions known as Thyrotoxicosis.
One’s particular BMR or RMR can be the standard used to balance one’s daily caloric budget by taking into account caloric EXPENDITIURES in the form of EXERCISE and your caloric DEPOSITS in the form of FOOD.
This information should enable the reader to disregard this kind of statement: Starvation diets don’t work because, when one eats less, the body lowers its BMR and you still gain weight even when eating less. This is total nonsense.
To be continued