There are three macronutrients required by humans namely; proteins, carbohydrates and lipids. Each of these contain calories per gram and it is required that individuals decide on their dietary needs to know which macronutrient best suits them. There are 4 calories per gram in carbohydrates. This is the macronutrient needed in the largest amounts by humans. This is because the nutrient is easily broken down during digestion to produce energy that drives metabolism.
Nutrient Functions
To provide energy needed for physical energy such as walking, brain activity and organs operations.
Carbohydrates take part in intestinal health and waste elimination.
Fiber which is indigestible carbohydrate reduces constipation during waste elimination
Carbohydrates are converted to glucose which is blood sugar, stored in the liver and muscles.
Role in Krebs Cycle
The above discusses how glucose is transferred to energy in form of Adenosine Triphosphate (ATP). Pyruvate formed in the cytoplasm is transferred to the mitochondria where energy is generated. An enzyme pyruvate carboxlase converts it to acetyl CoA which mixes with a four carbon compound to form a 6-carbon compound. Two molecules of NADH are formed and the 4-carbon compound undergoes three reactions forming guanosine triphosphate, FADH2 and NADH. The Krebs cycle provides energy electrons to form NADH and FADH2.
Food Sources
Simple carbohydrates are contained in fruits, vegetables, milk and sugars found during food processing. Complex carbohydrates are in whole grain cereals, breads, starchy vegetables and legumes.
Appropriate Food Preparation Techniques
Complexity of the carbohydrates determines the type of preparation. Those in fruits can be consumed directly. Cereals and nuts require isolation where they can be dried under vacuum to prevent thermal degradation, grounded to powder or defatted by solvent extraction.
Deficiency Effects
Ketosis is the immediate effect of deficiency of carbohydrates where there is excessive breakdown of protein and increased levels of fatigue and lack of energy. This deposits acidic molecules in the blood. Hypoglycemia is low blood sugar that results to diabetes due to low carbohydrates.
Toxicity Effects
Excessive consumption of carbohydrates could lead to obesity, insulin resistance poor concentration. Poor concentration and fatigue are because of inadequate blood flow to the brain. Insulin resistance results to obesity.
Digestion and Absorption
Carbohydrates are first digested in the mouth where starch is broken down into monosaccharide or disaccharides. Salivary amylase hydrolyses the starch and the broken-down starch finishes digestion in the small intestines. Monosaccharide such as glucose is absorbed directly in the bloodstream. Others are digested further and stored in the liver and muscles for energy.
Intake Recommendations
[Include a table of DRI by lifecycle stages including ages, pregnancy, lactation, and gender differences if applicable; indicate if your source is RDA (Recommended Dietary Intake, EAR (Estimated Average Requirements, Average Intakes (AI), and/or Tolerable Upper Intake Levels (UL); use APA format—see below]
Table 1
Dietary Reference Intakes for carbohydrates
Lifecycle Stage EAR(kg/d) RDA/AI (g/d) UL units
0-6 months 1.0 60 ND
7-12 months 1.0 95 ND
1-3 years 0.87 130 ND
4-8 years 0.76 130 ND
9-13 years 0.76 130 ND
14-18 years 0.73 130 ND
19-50 years 0.66 130 ND
51-70 years 0.66 130 ND
>71 years 0.66 130 ND
Pregnancy 0.88 175 ND
Lactation 1.05 210 ND
Conclusion
The above dietary requirements are the standard measures that are recommended by the Institute of Medicine. Following the requirements ensure that no one falls a victim of excessive consumption leading to obesity or deficiency which is accompanied by nutritional diseases as discussed above.
References
Dickens, F., Whelan, W. J., " Randle, P. J. (Eds.). (2014). Carbohydrate Metabolism: And Its Disorders. Elsevier.
Gandy, J. (2014). Manual of dietetic practice. John Wiley " Sons.
Tanca, A., Abbondio, M., Palomba, A., Fraumene, C., Manghina, V., Cucca, F., ... " Uzzau, S. (2017). Potential and active functions in the gut microbiota of a healthy human cohort. Microbiome, 5(1), 79.
