Basic food groups
Dietary carbohydrates are the main sources of readily available energy for man. In the hierarchy of food utilization in the human system, they, if available, are preferentially used over the other food groups as sources of energy. They can be derived from rice, root crops, sweet corn and potatoes, noodles, breads, pasta and cereals.
With low intake of carbohydrates, the next food group which will serve as source of energy will be the fats. These can be derived from bacon, butter, fish oils, poultry fat, coconut, peanuts, pork fat, egg yolk, avocado, whole milk, and fatty meats.
If we lack carbohydrates and fats, then proteins will be the last source of energy. Thus, in malnourished children who lack protein intake, the loss of muscles is very evident because they are consuming their own flesh which is largely made up of proteins. Aside from being the source of energy, proteins are needed in the repair of tissues, and they are derived from milk, poultry, meats, fish, eggs, cheese, soybeans, and legumes.
Interplay of the three food groups
In one of the previous articles of Powertec, total daily caloric requirement (TDCR) was mentioned, and it was defined as the amount of energy that a person needs to take in daily so that s/he could maintain his/her ideal body weight. If s/he takes more than the TDCR, s/he will gain weight; if s/he takes less than the TDCR, s/he will lose weight. Thus, the TDCR needs to be computed, and everyone is enjoined to strive taking in various kinds of food in a day whose total energy content is more or less equal to the TDCR.
For those who habitually go to the gym for physical exercises and for those with very active life, it is recommended that 70% of the TDCR must be taken from carbohydrates, while the remaining 30% will be taken from fats and proteins. A greater percentage is allotted to carbohydrates because as you physically exercise, you need to have readily available source of energy. Aside from physical exercises, in the morning, each one is in a hurry to meet his/her deadlines and various appointments; some need to move and drive fast to beat the traffic; more importantly, all need to replenish the energy that was burned while sleeping through the night—thus, the need to have immediate source of energy when the demand is high.
When the demand for energy is great, and the intake of carbohydrates is inadequate, a person will feel weak, lousy and dizzy because his/her muscles, brain, and blood cells—among other organs—are craving for glucose which is the simplest and smallest unit of carbohydrates. Grossly, when a person suddenly experiences hand tremors as s/he works and cannot withstand the cold air from the air conditioner, then s/he lacks carbohydrates which serve as fuel for muscle contraction and bodily warmth.
True enough, fats and proteins can serve as sources of energy; however, energy from these food groups is not readily available.Biochemically, if glucose will still be derived from fats and proteins, a very long and tedious processes will have to take place in our bodily systems. In short, it will take too much time and a number of biochemical reactions to take place before energy from fats and proteins can be used, unlike carbohydrates which can be immediately burned and used once they are needed. Since active people do a lot of bodily movements, such as walking, running and driving, they need to nourish themselves with enough carbohydrates before they hit the road.
Intake of fats is very much needed by people from cold countries because it provides more than twice the energy value of an equivalent weight of carbohydrates or proteins. They need it as rich source of bodily warmth. High intake of protein is needed by growing up children. For very active adults in tropical countries, a little of fats and proteins could be taken, but greater percentage should be derived from carbohydrates.
- Roth, Ruth A. Nutrition and Diet Therapy. Singapore: Delmar Learning, 2007.
- Castro, Jose S. “Practical insights on how to stay fit: Proper and adequate diet (3rd of a series)”. LifelinkMarch 2000: 30-31.