Clinical Nutrition

Comprehensive practice flashcards for Clinical Nutrition covering macronutrients, micronutrients, deficiency diseases, dietary guidelines, and the nutrition care process.

What is the definition of nutrients?

Substances found in foods that can promote health and minimize illness.

What is the definition of a balanced diet?

A diet which contains different types of food in such quantities and proportion that the requirements for proteins, fats, carbohydrates, vitamins and minerals and other nutrients are in proper quantity for maintaining the health, vitality and general well being.

What are Recommended Dietary Allowances (RDAs)?

Estimates of nutrients to be consumed daily to ensure the requirements of all individuals in a given population.

How are carbohydrates classified structurally, and what are the main subgroups?

Carbohydrates are divided into Simple Carbohydrates (monosaccharides and disaccharides) and Complex carbohydrates (Polysaccharides).

Which specific sugars belong to the monosaccharides and disaccharides?

Monosaccharides include glucose, fructose, and galactose; disaccharides include maltose, sucrose, and lactose.

What monosaccharide components form sucrose, lactose, and maltose?

Sucrose is formed by Glucose + Fructose; Lactose is formed by Glucose + Galactose; Maltose is formed by Glucose + Glucose.

Which polysaccharides are classified as complex carbohydrates?

Starch, glycogen, and cellulose.

What is the primary function of carbohydrates, and which cells depend on glucose exclusively?

The main function of carbohydrate is to provide energy; the brain and red blood cells use glucose exclusively.

Where does carbohydrate digestion begin and continue, and what enzyme initiates it?

Digestion begins in the mouth with salivary amylase, then continues in the small intestines.

In what form must carbohydrates be for absorption to occur?

Carbohydrate absorption is only in monosaccharide form.

How is excess ingested carbohydrate handled in normal individuals compared to diabetic patients?

In normal patients, excess glucose is stored in the liver or muscle; in diabetic patients, excess glucose remains in circulation.

How do insulin, glucagon, and adrenaline influence blood glucose levels?

Insulin decreases glucose in blood by stimulating glycogen formation (storing glucose); Glucagon and Adrenaline increase glucose in blood by stimulating glycogen destruction (depleting glucose storage).

What is the Recommended Daily Allowance (RDA) of carbohydrates for adults, and when does requirement increase?

The RDA for adults is $130\,\text{g}$; requirement increases during pregnancy and lactation.

What are the clinical benefits of dietary fibers?

They lower serum LDL levels, reduce constipation, promote feeling of fullness, and slow gastric emptying (providing long-term glucose control in patients with diabetes mellitus).

What effect do monounsaturated fatty acids have on cholesterol, and what are their food sources?

They appear to lower LDL ("bad") cholesterol and help raise levels of HDL ("good") cholesterol; food sources include olives, olive oil, avocados, peanuts, peanut oil, and canola oil.

What effect do polyunsaturated fatty acids have on cholesterol, and what are their common sources?

They seem to lower total cholesterol levels; food sources include many vegetable oils, such as corn oil, soybean oil, and safflower oil.

How do saturated fatty acids affect blood cholesterol, and what food sources contain them?

They appear to raise the level of LDL ("bad") cholesterol in the bloodstream; food sources include meat, poultry skin, whole-milk dairy products, coconut oil, and palm oil.

What is hydrogenation, and what type of fatty acid does it generate?

The process in which missing hydrogen atoms are added to an unsaturated fat to make it firmer in texture, forming trans fatty acids.

What are the health risks associated with consuming trans fats?

They decrease good cholesterol, increase bad cholesterol and inflammation, and increase the risk of heart disease and cancer.

Which foods are notably high in dietary cholesterol?

Animal products including meat, poultry, fish, egg yolks, liver/organ meats, and some shellfish.

What physiological roles distinguish low-density lipoproteins (LDL) from high-density lipoproteins (HDL)?

Excess LDL deposits in artery walls, increasing heart disease and stroke risk ("bad cholesterol"); HDL picks up excess cholesterol and transports it back to the liver ("good cholesterol").

What distinguishes essential fatty acids from nonessential fatty acids, and what are examples of each?

Essential fatty acids cannot be synthesized in the body and must be supplied by diet (e.g., linolenic acid); nonessential fatty acids can be formed within the body (e.g., palmitic acid).

How are fats digested and absorbed in the human gastrointestinal tract?

Fats are digested using pancreatic lipase enzyme assisted by bile, and the main site of absorption is the proximal portion of the small intestine.

What clinical methods are recommended to lower fat and cholesterol in the diet?

Exercise, replacing saturated fats with unsaturated fats, choosing lean cuts of meat, and steaming or boiling foods instead of cooking them in oil or fat.

What are the two categories of amino acids, and which amino acids belong to each category?

Essential Amino acids cannot be synthesized in the body (Tryptophan, Histidine, and Leucine); Non-Essential Amino acids can be synthesized inside the body (Alanine, Arginine, and Serine).

Where are proteins digested, where are amino acids absorbed, and what nitrogenous intermediates accumulate in organ failure?

Proteins are digested in the stomach by pepsin and further absorbed by pancreatic enzymes in the small intestine; amino acids are absorbed in the liver. Ammonia accumulates in liver insufficiency, and urea accumulates in renal insufficiency.

What is the Satiety Index, and how are nutrients ranked by it from most to least filling?

The Satiety Index is the measurement of how filling a nutrient is. Ranking: 1. Proteins (most filling), 2. Complex Carbohydrates, 3. Simple Carbohydrates, 4. Fats (least filling).

How many calories are provided per gram of fat, protein, and carbohydrates?

Fat provides $9\,\text{calories per gram}$; Protein provides $4\,\text{calories per gram}$; Starch and sugars (carbohydrates) provide $4\,\text{calories per gram}$.

What are micronutrients and how are they broadly classified?

Classes of food consumed in milligrams or micrograms to meet specific metabolic needs; classified into Vitamins (water-soluble and fat-soluble), Minerals, and Trace Elements.

What key properties distinguish water-soluble vitamins from fat-soluble vitamins?

Water-soluble vitamins (B complex, C, Folic Acid, Biotin) are available in food, well absorbed, and have limited storage; fat-soluble vitamins (A, D, E, K) are easily storable and not required daily.

What is the metabolic function of Vitamin B1 (Thiamine), and what results from its deficiency?

Needed for energy production; deficiency leads to beriberi, a disease affecting peripheral nerves that can cause anorexia and weight loss.

What clinical condition affecting the mouth and tongue is displayed here, and what nutrient deficiency causes it?

Mouth and tongue inflammation (ariboflavinosis), caused by Vitamin B2 (Riboflavin) deficiency.

What is the role of Vitamin B3 (Niacin), and what condition is caused by its deficiency?

Needed for fat metabolism; deficiency leads to Pellagra, characterized by the 3 D's: Dermatitis, Diarrhea, and Dementia.

What are the roles of Vitamin B5, Vitamin B6, Vitamin B7, and Vitamin B9?

B5 (Pantothenic Acid): Hormones production; B6 (Pyridoxine): Neurotransmitters synthesis and mood regulation; B7 (Biotin): Hair and nails health; B9 (Folic Acid): Synthesis of DNA/RNA.

Why do Vitamin B12 (Cobalamin) deficiencies typically arise from malabsorption rather than low intake?

Unlike other vitamins, Vitamin B12 can be stored in the liver for many years, so deficiencies arise from malabsorption rather than intake.

What is the metabolic role of Vitamin C, and what disease results from its deficiency?

Needed for collagen production and maintaining immune system health; deficiency leads to scurvy (bleeding gums).

What are the primary function, deficiency symptoms, and toxicity signs of Vitamin A (Retinol)?

Maintains rods of the retina for night vision; deficiency causes night blindness; toxicity can cause nausea, vomiting, and liver damage.

What is the function of Vitamin D (Calciferol), and what occur during deficiency or toxicity?

Needed for intestinal calcium absorption; deficiency causes osteomalacia and rickets (common in dark-skinned individuals due to melanin restricting synthesis); toxicity causes tissue calcification and kidney stones.

What is the role of Vitamin K, and what is the consequence of its deficiency?

Needed for synthesis of coagulation factors; deficiency can lead to severe bleeding.

How do minerals differ from trace elements in terms of quantity in the body?

Minerals are present in amounts greater than $100\,\text{mg}$ up to $100\,\text{g}$; Trace Elements are present in the range of micrograms to milligrams.

What are the functions and deficiency symptoms of Calcium and Magnesium?

Calcium is needed for bone/teeth structure and muscle contraction (deficiency causes osteopenia); Magnesium is used in bones and muscles (deficiency causes anorexia and psychosis).

Where is iron absorbed, what factors alter its absorption, and what are its lethal toxicity thresholds?

Absorbed in the small intestine; absorption increases with vitamin C and decreases with oxalate and fibers; toxicity is lethal at concentration $> 3000\,\text{mg}$ in children or $250\,\text{mg/kg}$ in adults.

What pathological neck enlargement is shown in this diagram, and which trace element deficiency produces it?

Goitre, which results from Iodine deficiency affecting thyroid hormone synthesis.

What is the function of Zinc, and what are the effects of its deficiency?

Used in maintaining immune system health and enzyme synthesis; deficiency leads to impaired growth and immune system.

What are the four sequential steps of the nutrition care process?

1. Nutrition assessment, 2. Nutrition diagnosis, 3. Nutrition intervention, 4. Nutrition monitoring and evaluation.

What are the direct and indirect methods used in Nutritional Assessment?

Direct methods: Dietary assessment, Biochemical data, Anthropometric measurements, and Clinical assessment; Indirect methods: Cultural and Social habits.

What are the main components of a dietary assessment?

Food diary (food intake over $1\text{--}7\,\text{days}$, such as a 24-hour recall or 3-day diary), food frequency questionnaire (~$100\,\text{items}$), and dietary history over a long period.

Which biochemical laboratory test is considered the most important and useful index in nutritional assessment?

Hemoglobin analysis.

Which anthropometric measurement is being conducted in this image?

Mid-arm circumference measurement.

Which anthropometric dimension is being measured in this image?

Head circumference measurement.

Which anthropometric measurement is demonstrated in this image?

Chest circumference measurement.

What is the formula for calculating Body Mass Index (BMI)?

$$\text{BMI} = \frac{\text{weight (kg)}}{[\text{Height (m)}]^2}$$

What are the adult BMI classifications and their corresponding numerical cutoffs?

Under Weight: $< 18.5$; Healthy weight range: $18.5\text{--}24.5$; Overweight (grade 1 obesity): $25\text{--}30$; Obese (grade 2 obesity): $> 30\text{--}40$; Very obese (morbid or grade 3 obesity): $> 40$.

What nutritional deficiency causes Marasmus and Kwashiorkor?

Protein energy malnutrition.

What are the specific components and goals of Nutritional Monitoring and Evaluation?

Monitoring tracks progress across dietary intake, anthropometric measurements, biochemical data, and clinical symptoms; Evaluation compares current findings with previous findings; the nutrition care plan is modified as needed based on progress.