Nutrition: Macronutrients & Energy

What are the physiological fuel values (kcal/g) for carbohydrates, proteins, and fats?

Carbohydrates provide 4 kcal/g, proteins provide 4 kcal/g, and fats provide 9 kcal/g.

What defines an 'essential' amino acid in human nutrition?

An amino acid that cannot be synthesized by the body de novo and must be obtained through dietary intake.

What is the definition of Basal Metabolic Rate (BMR)?

The minimum number of calories required to maintain vital physiological functions (e.g., breathing, circulation) while the body is at complete rest.

What is the Acceptable Macronutrient Distribution Range (AMDR) for carbohydrates in adults?

45% to 65% of total daily caloric intake.

What is the primary structural difference between saturated and unsaturated fatty acids?

Saturated fats have no double bonds between carbon atoms, while unsaturated fats contain one or more double bonds in the hydrocarbon chain.

Which macronutrient has the highest satiety value and the highest thermic effect of food (TEF)?

Protein.

What does a 'negative nitrogen balance' typically indicate in a clinical setting?

It indicates that nitrogen excretion exceeds intake, signifying muscle wasting or catabolism often seen in starvation, severe trauma, or major burns.

How does Glycemic Load (GL) differ from Glycemic Index (GI)?

GI measures how quickly a food raises blood glucose, while GL accounts for both the GI and the actual amount of carbohydrate in a standard serving size.

What are the two primary essential fatty acids that humans must consume?

Alpha-linolenic acid (an Omega-3 fatty acid) and Linoleic acid (an Omega-6 fatty acid).

What is a 'complete protein' and provide an example of a plant-based source?

A protein source containing all nine essential amino acids in adequate proportions; soy and quinoa are common plant-based examples.