WGU D440 Health and Wellness Through
Nutritional Science Study Guide 2026 –
Complete Review and Exam
SECTION 1: CORE NUTRITION CONCEPTS & MACRONUTRIENTS
1. What is the correct definition of nutrition?
A) The study of food processing and packaging
B) The intake of food, considered in relation to the body's dietary needs
C) The study of pharmacological effects of food additives
D) The practice of eliminating specific food groups for health
B) The intake of food, considered in relation to the body's dietary needs
Rationale: Nutrition is defined as the intake of food considered in relation to the body's
dietary needs. Nutrition science studies how food components affect metabolism, health,
performance, and disease resistance .
2. Which macronutrient provides the most concentrated source of energy per gram?
A) Protein
B) Carbohydrates
C) Fat
D) Water
C) Fat
Rationale: Fat provides 9 kcal/g, making it the most energy-dense macronutrient.
Carbohydrates and protein each provide 4 kcal/g .
3. A patient consumes 16 grams of fat. How many kilocalories has the patient consumed from
fat?
A) 64 kcal
B) 112 kcal
C) 144 kcal
D) 160 kcal
C) 144 kcal
, Rationale: Fat provides 9 kcal/g. Calculation: 16 g × 9 kcal/g = 144 kcal .
4. Which of the following are classified as macronutrients? Select all that apply.
A) Carbohydrates
B) Proteins
C) Vitamins
D) Fats
E) Minerals
A) Carbohydrates | B) Proteins | D) Fats
Rationale: Macronutrients are required in large amounts and provide energy: carbohydrates
(4 kcal/g), proteins (4 kcal/g), and fats (9 kcal/g). Vitamins and minerals are micronutrients
required in smaller amounts .
5. What is the Acceptable Macronutrient Distribution Range (AMDR) for carbohydrates?
A) 10–20% of total calories
B) 20–35% of total calories
C) 45–65% of total calories
D) 65–75% of total calories
C) 45–65% of total calories
Rationale: The AMDR for carbohydrates is 45–65% of total daily calories. Proteins are 10–
35%, and fats are 20–35% .
6. Which macronutrient is the body's preferred and primary energy source, especially for the
brain?
A) Protein
B) Carbohydrates
C) Fats
D) Alcohol
B) Carbohydrates
Rationale: Carbohydrates are broken down into glucose, the preferred energy source for the
brain and body. The brain relies almost exclusively on glucose .
7. What is the primary function of protein in the body?
A) Primary energy source
B) Tissue building, repair, and maintenance
,C) Hormone synthesis only
D) Insulation and temperature regulation
B) Tissue building, repair, and maintenance
Rationale: Protein is essential for growth, repair, and maintenance of body tissues. It also
regulates fluid balance, maintains acid-base balance, produces antibodies, and provides
enzymes and hormones .
8. Which of the following are functions of fats in the body? Select all that apply.
A) Concentrated energy source
B) Protection of internal organs
C) Enhancement of fat-soluble vitamin absorption
D) Primary source of glucose for the brain
E) Maintenance of body temperature
A) Concentrated energy source | B) Protection of internal organs | C)
Enhancement of fat-soluble vitamin absorption | E) Maintenance of body temperature
Rationale: Fats provide concentrated energy (9 kcal/g), protect internal organs, enhance
absorption of vitamins A, D, E, and K, and maintain body temperature. Glucose for the brain
comes from carbohydrates .
9. A nurse is calculating intake for a patient who consumed 6 ounces of coffee and 8 ounces of
water. How many milliliters should the nurse record?
A) 360 mL
B) 420 mL
C) 480 mL
D) 540 mL
B) 420 mL
Rationale: Conversion factor: 1 ounce = 30 mL. Total intake: (6 oz + 8 oz) × 30 mL/oz = 14 ×
30 = 420 mL .
10. Which food source contains all nine essential amino acids?
A) Lentils
B) Eggs
C) Brown rice
D) Peanut butter
, B) Eggs
Rationale: Eggs are an animal product containing all nine essential amino acids, making
them a complete protein. Most plant proteins are incomplete, lacking one or more essential
amino acids .
11. What is the daily recommended intake of carbohydrates for adults according to the DRI?
A) 100 g/day
B) 225–325 g/day
C) 500 g/day
D) 50 g/day
B) 225–325 g/day
Rationale: The DRI recommends 225–325 grams of carbohydrates per day for adults based
on a 2000 kcal diet, providing adequate glucose for brain and body functions .
12. Which statement accurately defines health?
A) Absence of disease or illness
B) Complete physical, mental, and social well-being
C) Ability to perform daily activities without fatigue
D) Balance between calorie intake and expenditure
B) Complete physical, mental, and social well-being
Rationale: Health is defined as complete physical, mental, and social well-being, not merely
the absence of disease. This definition encompasses multiple dimensions of wellness .
13. Which characteristics are signs of good nutrition? Select all that apply.
A) Smooth skin
B) Clear and bright eyes
C) Resistance to infections
D) Increase in adipose tissue
E) High weight-to-height ratio
A) Smooth skin | B) Clear and bright eyes | C) Resistance to infections
Rationale: Signs of good nutrition include smooth skin, clear and bright eyes, and resistance
to infection. Increased adipose tissue and high weight-to-height ratio may indicate
overnutrition, not good nutrition .
Nutritional Science Study Guide 2026 –
Complete Review and Exam
SECTION 1: CORE NUTRITION CONCEPTS & MACRONUTRIENTS
1. What is the correct definition of nutrition?
A) The study of food processing and packaging
B) The intake of food, considered in relation to the body's dietary needs
C) The study of pharmacological effects of food additives
D) The practice of eliminating specific food groups for health
B) The intake of food, considered in relation to the body's dietary needs
Rationale: Nutrition is defined as the intake of food considered in relation to the body's
dietary needs. Nutrition science studies how food components affect metabolism, health,
performance, and disease resistance .
2. Which macronutrient provides the most concentrated source of energy per gram?
A) Protein
B) Carbohydrates
C) Fat
D) Water
C) Fat
Rationale: Fat provides 9 kcal/g, making it the most energy-dense macronutrient.
Carbohydrates and protein each provide 4 kcal/g .
3. A patient consumes 16 grams of fat. How many kilocalories has the patient consumed from
fat?
A) 64 kcal
B) 112 kcal
C) 144 kcal
D) 160 kcal
C) 144 kcal
, Rationale: Fat provides 9 kcal/g. Calculation: 16 g × 9 kcal/g = 144 kcal .
4. Which of the following are classified as macronutrients? Select all that apply.
A) Carbohydrates
B) Proteins
C) Vitamins
D) Fats
E) Minerals
A) Carbohydrates | B) Proteins | D) Fats
Rationale: Macronutrients are required in large amounts and provide energy: carbohydrates
(4 kcal/g), proteins (4 kcal/g), and fats (9 kcal/g). Vitamins and minerals are micronutrients
required in smaller amounts .
5. What is the Acceptable Macronutrient Distribution Range (AMDR) for carbohydrates?
A) 10–20% of total calories
B) 20–35% of total calories
C) 45–65% of total calories
D) 65–75% of total calories
C) 45–65% of total calories
Rationale: The AMDR for carbohydrates is 45–65% of total daily calories. Proteins are 10–
35%, and fats are 20–35% .
6. Which macronutrient is the body's preferred and primary energy source, especially for the
brain?
A) Protein
B) Carbohydrates
C) Fats
D) Alcohol
B) Carbohydrates
Rationale: Carbohydrates are broken down into glucose, the preferred energy source for the
brain and body. The brain relies almost exclusively on glucose .
7. What is the primary function of protein in the body?
A) Primary energy source
B) Tissue building, repair, and maintenance
,C) Hormone synthesis only
D) Insulation and temperature regulation
B) Tissue building, repair, and maintenance
Rationale: Protein is essential for growth, repair, and maintenance of body tissues. It also
regulates fluid balance, maintains acid-base balance, produces antibodies, and provides
enzymes and hormones .
8. Which of the following are functions of fats in the body? Select all that apply.
A) Concentrated energy source
B) Protection of internal organs
C) Enhancement of fat-soluble vitamin absorption
D) Primary source of glucose for the brain
E) Maintenance of body temperature
A) Concentrated energy source | B) Protection of internal organs | C)
Enhancement of fat-soluble vitamin absorption | E) Maintenance of body temperature
Rationale: Fats provide concentrated energy (9 kcal/g), protect internal organs, enhance
absorption of vitamins A, D, E, and K, and maintain body temperature. Glucose for the brain
comes from carbohydrates .
9. A nurse is calculating intake for a patient who consumed 6 ounces of coffee and 8 ounces of
water. How many milliliters should the nurse record?
A) 360 mL
B) 420 mL
C) 480 mL
D) 540 mL
B) 420 mL
Rationale: Conversion factor: 1 ounce = 30 mL. Total intake: (6 oz + 8 oz) × 30 mL/oz = 14 ×
30 = 420 mL .
10. Which food source contains all nine essential amino acids?
A) Lentils
B) Eggs
C) Brown rice
D) Peanut butter
, B) Eggs
Rationale: Eggs are an animal product containing all nine essential amino acids, making
them a complete protein. Most plant proteins are incomplete, lacking one or more essential
amino acids .
11. What is the daily recommended intake of carbohydrates for adults according to the DRI?
A) 100 g/day
B) 225–325 g/day
C) 500 g/day
D) 50 g/day
B) 225–325 g/day
Rationale: The DRI recommends 225–325 grams of carbohydrates per day for adults based
on a 2000 kcal diet, providing adequate glucose for brain and body functions .
12. Which statement accurately defines health?
A) Absence of disease or illness
B) Complete physical, mental, and social well-being
C) Ability to perform daily activities without fatigue
D) Balance between calorie intake and expenditure
B) Complete physical, mental, and social well-being
Rationale: Health is defined as complete physical, mental, and social well-being, not merely
the absence of disease. This definition encompasses multiple dimensions of wellness .
13. Which characteristics are signs of good nutrition? Select all that apply.
A) Smooth skin
B) Clear and bright eyes
C) Resistance to infections
D) Increase in adipose tissue
E) High weight-to-height ratio
A) Smooth skin | B) Clear and bright eyes | C) Resistance to infections
Rationale: Signs of good nutrition include smooth skin, clear and bright eyes, and resistance
to infection. Increased adipose tissue and high weight-to-height ratio may indicate
overnutrition, not good nutrition .
