Registered Dietitian (China) cheat sheet

Atwater factors: carbohydrate 4 kcal/g, protein 4 kcal/g, fat 9 kcal/g, alcohol 7 kcal/g, dietary fiber 2 kcal/g (Chinese labeling convention).

Protein digestibility-corrected amino acid score (PDCAAS) = lowest amino acid ratio × true fecal digestibility; limiting amino acid in cereals is lysine, in legumes methionine/cysteine.

Glycemic index = (incremental AUC for 50 g available carbohydrate of test food ÷ same for reference glucose) × 100; glycemic load = GI × available carbohydrate (g) ÷ 100.

Essential fatty acids: linoleic acid (n-6) and alpha-linolenic acid (n-3); conversion to arachidonic and EPA/DHA is limited, so long-chain n-3 is conditionally essential in infants.

Energy expenditure components: resting metabolic rate ~60-70%, thermic effect of food ~10%, physical activity ~20-30%; 1 kcal = 4.184 kJ.

Fat-soluble vitamins A, D, E, K are absorbed with dietary fat via micelles and transported in chylomicrons; water-soluble vitamins absorbed into portal blood.

Iron absorption: heme iron 15-35% absorbed, non-heme 2-20%; ascorbic acid and meat enhance, phytate, tannins, calcium and polyphenols inhibit.

Calcium homeostasis is regulated by parathyroid hormone, calcitriol (1,25-(OH)2-D3) and calcitonin acting on bone, kidney and intestine.

Maillard browning occurs between reducing sugars and amino groups of proteins at high temperature, reducing available lysine and forming acrylamide in starchy foods.

Thiamin, riboflavin and vitamin C are the most heat- and water-labile vitamins; loss increases with cooking time, surface area, and volume of cooking water.

Danger zone for bacterial growth is 5-60 °C; keep hot foods above 60 °C and cold foods below 5 °C; two-hour rule for perishable food at room temperature.

Hazard categories: biological (Salmonella, Staphylococcus aureus enterotoxin, Clostridium botulinum, Listeria), chemical (pesticide residues, aflatoxin, heavy metals), physical (glass, metal).

Aflatoxin is produced by Aspergillus flavus in moldy peanuts and corn; it is heat-stable and a recognized hepatocarcinogen.

Nitrite in cured meats inhibits Clostridium botulinum and combines with amines to form nitrosamines; ascorbate is added to block nitrosamine formation.

HACCP has seven principles: hazard analysis, determine CCPs, set critical limits, monitor, corrective actions, verification, record keeping.

Food additives must be on the permitted list, used within maximum levels, and be technically justified; preservatives, antioxidants, colorants and emulsifiers are common classes.

BMI = weight (kg) ÷ height (m)²; Chinese adult cutoffs: underweight <18.5, normal 18.5-23.9, overweight 24.0-27.9, obese ≥28.0.

Waist circumference thresholds for Chinese adults: central obesity when men ≥90 cm and women ≥85 cm.

Dietary reference intakes include EAR, RNI, AI and UL; RNI ≈ EAR + 2 SD, covering about 97-98% of the population.

24-hour recall is quick but relies on memory; food frequency questionnaire captures habitual intake; weighed food records are most accurate but impose burden.

Biochemical markers: serum albumin (half-life ~20 days) for chronic protein status, prealbumin (~2 days) for short-term change, hemoglobin for iron-deficiency anemia.

Acceptable macronutrient distribution for Chinese adults: carbohydrate 50-65% energy, fat 20-30% energy, protein 10-15% energy.

Chinese Dietary Guidelines emphasize food variety, adequate vegetables, fruits, dairy, whole grains and limiting salt (<5 g/day) and added sugar (<25 g/day).

Subjective Global Assessment combines weight change, dietary intake, GI symptoms, functional capacity and physical exam to classify mild, moderate or severe malnutrition.

Diabetes medical nutrition therapy: consistent carbohydrate intake, carbohydrate counting, low glycemic index choices, and individualized energy for weight goals.

Diabetic kidney disease: protein 0.8 g/kg/day when eGFR is reduced; avoid very high protein; control sodium <2 g/day and phosphorus and potassium as indicated.

Hypertension: DASH-style eating with potassium-rich fruits and vegetables, low sodium (<5 g salt/day), and weight control lower blood pressure.

Chronic kidney disease: limit sodium, potassium and phosphorus; dialysis patients need higher protein (1.0-1.2 g/kg/day) due to losses.

Liver cirrhosis with ascites: sodium restriction and adequate protein 1.2-1.5 g/kg/day; do not over-restrict protein as it worsens malnutrition.

Critical care: early enteral nutrition within 24-48 hours when hemodynamically stable; calculate energy needs with indirect calorimetry or predictive equations.

Dysphagia: texture-modified diets and thickened fluids reduce aspiration risk; speech-language assessment guides consistency level.

Hyperlipidemia: reduce saturated fat (<7% energy) and trans fat, increase soluble fiber and plant sterols/stanols to lower LDL cholesterol.

Nutrition surveillance tracks anthropometry, biochemical indicators, dietary intake and mortality to monitor population trends and inform policy.

The first 1,000 days (conception to age 2) is a critical window for growth and development; stunting reflects chronic undernutrition.

Exclusive breastfeeding for the first 6 months, then complementary foods from 6 months with continued breastfeeding to 2 years or beyond.

Iodized salt prevents iodine deficiency disorders; universal salt iodization is a core public health measure.

Folic acid supplementation before and during early pregnancy reduces neural tube defects.

Nutrition education uses behavior-change theory, social marketing and culturally appropriate messages to improve dietary practices.

Food fortification and supplementation programs target micronutrient deficiencies (iron, vitamin A, iodine) in vulnerable groups.

Double burden of malnutrition: coexistence of undernutrition and obesity/overweight within the same population or household.

Pregnancy: additional energy about 300 kcal/day in the second and third trimesters; increased needs for protein, iron, folate, calcium and iodine.

Recommended gestational weight gain depends on pre-pregnancy BMI; both inadequate and excessive gain increase maternal and fetal risks.

Infancy: breast milk or infant formula is the sole source of nutrition for the first 6 months; introduce iron-rich complementary foods at 6 months.

Childhood and adolescence: rapid growth increases energy, protein, calcium and iron needs, especially during puberty.

Adulthood: maintain energy balance, adequate calcium and vitamin D for bone health, and limit salt, sugar and saturated fat.

Aging: decreased energy needs but maintained or increased protein (about 1.0-1.2 g/kg/day) to prevent sarcopenia; vitamin D and calcium for bone.

Older adults are at risk of dehydration due to reduced thirst; monitor fluid intake.

Lactation: increased energy and fluid needs; energy cost of milk production is partly met by fat stores gained in pregnancy.

Food service systems include conventional (cook-serve), commissary (cook-chill/freeze), ready-prepared and assembly-serve; each has different labor, equipment and food-safety implications.

Menu planning considers nutritional adequacy, client preferences, cost, seasonality, equipment capacity and labor.

Standardized recipes ensure consistent yield, quality and nutrient content; yield testing determines portion cost.

Food cost control uses purchasing specifications, inventory rotation (FIFO), portion control and waste tracking.

HACCP-based food safety management in food service includes temperature monitoring, supplier approval and staff training.

Food procurement should use written specifications for quality, quantity, packaging and delivery; competitive bidding controls cost.

Quality management uses audits, client satisfaction surveys and key performance indicators such as meal accuracy and complaint rates.

Therapeutic diet modification in food service requires communication between dietitian, kitchen and nursing to ensure correct trays.

Scope of practice: dietitians provide medical nutrition therapy, nutrition assessment and counseling within their training and licensure; refer outside scope.

Informed consent requires disclosure, comprehension, voluntariness and capacity before nutrition interventions or research participation.

Confidentiality: protect client health information; share only with consent or as required by law.

Evidence-based practice integrates best available research, clinical expertise and client values and preferences.

Levels of evidence: systematic reviews and randomized controlled trials rank above cohort studies, case reports and expert opinion.

Conflict of interest must be disclosed; avoid endorsing products for personal gain.

Research ethics: institutional review board approval, voluntary participation, right to withdraw, and protection of vulnerable populations.

Professional communication uses active listening, open-ended questions, motivational interviewing and plain language to support behavior change.