Digestive SystemNUTRITION
Energy
Energy allows a physical system to do work
The potential energy found in food is measured in Calories with a capital C. The Calorie is also known as a kilocalorie (kcal).
A single Calorie is equal to the amount of heat required to raise the temperature of 1 kilogram of water 1°C.
The basal metabolic rate (BMR) relates to the amount of Calories necessary to sustain a body at rest for one day. Physical activity means most people will need to consume 20-70% more than their BMR to stay healthy.
Macronutrients
Nutrients are chemicals that the body need for Energy, growth, and maintenance.
Macronutrients include the fats, proteins, and carbohydrates. Substances that the body requires in high amounts.
Carbohydrates:
Sugars and Starches are carbohydrates
Sugars like fructose are found in fruit, while starches can be found in bread, pasta, and potatoes.
50% of your diet should be in carbohydrates.
They yield about 4 Calories per gram once digested.
Proteins:
Proteins are made of amino acids
Protein can be found in meat, legumes (beans, peas, and soy), and grains (rice, corn, and wheat)
There are 20 amino acids 9 of which are essential for adults.
We can produce nonessential amino acids if sufficient amounts of the essential amino acids are present.
Should make up about 25% of your diet.
Yields 4 Calories per gram.
Fats (lipids):
Include oils and solid fats
Less healthful
Saturated fats: mostly from animal sources such as meat and dairy products. Some oils
such as coconut and palm oils contain high amounts of these fats.
Trans-unsaturated fats: unsaturated fatty acids that are artificially produced.
More healthful
Poly-unsaturated fats: corn oil and soybean oil
Monounsaturated fats: canola oil and olive oil
Should be about 25-35% of your diet.
Yields 9 Calories per gram.
Micronutrients Micronutrients are essential to the body in small amounts.
Fruits and vegetables are good sources.
These include vitamins and minerals.
Vitamins: organic chemicals needed by the body for normal functioning and good health.
Fat soluble: enter the body with fats, stored in adipose tissue, excess not easily eliminated and can be toxic.
Water soluble: is not stored and excess is eliminated
Many are coenzymes, molecules that combine with proteins to create enzymes.
Vitamin deficiency can result in many health problems, such as scurvy and anemia.
Minerals: Elements that the body needs in relatively small amounts.
Amount required varies greatly depending on the mineral.