Components of a Balanced Diet and Their Functions
Functions of Each Components (Carbohydrate, Protein & Lipids ) of A Balanced Diet:
Functions of Dietary Carbohydrates (CHO):
1. Major sources of energy:
Carbohydrates are the principal source of energy, supplying 60-80% of the caloric requirements of the body.
2. Protein sparing action:
Use of carbohydrates for calorie purpose spares the protein for its body building & growth function.
3. Absolute requirement by brain:
The brain & other parts of CNS are dependent on glucose for energy. Prolonged hypoglycemia may lead to irreversible brain damage.
4. Energy supply for muscle work:
The muscle glycogen is broken down to lactic acid (glycolysis) to provide energy for muscle contraction.
5. Required for the oxidation of fat:
Acetyl COA is the product that is formed in fatty acid oxidation. For its further oxidation via TCA cycle, Acetyl COA combines with oxaloacetate; the latter is predominantly derived from carbohydrates. It may therefore be stated Fat burns in a fuel of carbohydrate’. Excess utilization of fats coupled with deficiency of carbohydrates leads to ketosis.
6. Synthesis of pentose sugars:
Pentose sugars (e.g. Ribose & deoxyribose) are the constituents of several compounds in the body, e.g. nucleic acids (DNA, RNA), co-enzymes (NADH FAD) etc.
7. Synthesis of non-essential amino acids:
The intermediates of carbohydrate metabolism, mainly the ketoacids (e.g. pyruvic acid), serve as precursors for the synthesis of non-essential amino acids.
8. Synthesis of fat:
Excess consumption of CHO leads to the formation of fat which is stored in the adipose tissue.
9. Importance of non-digestible carbohydrates:
These are the carbohydrates not utilized by the body. Yet, they are important since they improve bowel motility, prevent constipation, lower cholesterol absorption and improve glucose tolerance etc.
Role of Proteins In Diet/Nutrition:
Proteins are traditionally regarded as body building foods. They play the following roles –
- Proteins are the fundamental basis of cell structure & its function.
- All the enzymes, several hormones, immunoglobulins, transport carriers etc. are proteins.
- Milk formation during lactation.
- 10-15% of total body energy is derived from protein.
- Proteins are involved in osmotic pressure maintenance, blood clotting, muscle contraction etc.
- Repair & maintenance of body tissue.
- Act as buffer & maintain acid-base balance.
- Fetal development during pregnancy.
- During starvation, proteins serve as major supplier of energy. Structural proteins serve as storage proteins’ to meet the emergency energy needs of the body.
You can also read Physical Assessment of Well Woman Checklist by Age
Major Nutritional Functions of Lipids:
Dietary lipids have 2 major nutritive functions:
- Supply triacylglycerol (TAG) that normally constitute about 90% of dietary lipids which is a concentrated source of fuel to the body.
- Helps in absorption of fat soluble vitamins (A, D, E & K).
- Provide essential fatty acids (EFA): Functions of EFA are-
- Essential fatty acids are the structural components of biological membranes.
- They participate in the transport and utilization of cholesterol.
- Prevent fat accumulation in the liver.
- They are required for the synthesis of prostaglandins.
- Maintain proper growth and reproduction of the organisms.
Maria Khatun Mona is a Founder and Editor of Nursing Exercise Blog. She is a Nursing and Midwifery Expert. Currently she is working as a “Senior Staff Nurse” at “Dinajpur Medical College Hospital”, Bangladesh. She has great passion in writing different articles on Nursing and Midwifery. Mail her at “maria.mona023@gmail.com”