Tamil Nadu HSE Second Year Nutrition and Dietetics common mistakes
Tamil Nadu HSE Second Year Nutrition and Dietetics · Understand the traps and how to avoid them.
Calculating energy yield of a mixed meal by adding the raw gram weights of carbohydrate, protein and fat and calling that the total energy, or applying the Atwater factors to the wrong fraction (e.g. using 4 kcal/g for fat).
Candidates memorise '4-4-9' but practise only on single pure nutrients, so under exam pressure they mix up which factor goes with which macronutrient and forget that the gram figures must be the actual nutrient grams, not the food weight or the cooked weight.
What to do instead
Before every calculation, write the three-column table: nutrient | grams | factor | kcal, and fill the factor column first (carbohydrate 4, protein 4, fat 9, alcohol 7). Then total the kcal column and check plausibility: a 500 kcal meal cannot contain 200 g of fat. Do ten mixed-food drills where you first extract nutrient grams from a food composition table and only then multiply.
Confusing BMR with total energy expenditure and using BMR alone to plan a diet, or applying PAL multipliers to the wrong reference (e.g. multiplying RDA instead of BMR).
BMR, RMR, TEF and physical activity allowance are taught together and the textbook formula chains them, so candidates drop one link or multiply the PAL by the RDA value rather than by BMR.
What to do instead
Use a fixed written chain every time: BMR (from the Schofield/Harris-Benedict value or the kJ/kg/hour method) × PAL = TEE; then TEE ± adjustment for weight goal = energy prescription. State each intermediate number on the answer sheet so a marker can see which quantity you multiplied. Practise five cases with different activity levels and check that sedentary TEE is roughly 1.4-1.5 × BMR.
Listing 'vitamins and minerals' as a single answer when asked which nutrient is deficient, or naming the deficiency disease without the specific nutrient (e.g. saying 'night blindness is a vitamin deficiency').
Micronutrients are revised as a block and the exam often asks for the disease, so candidates stop at the disease name and never link it to retinol, thiamine, riboflavin, niacin, ascorbic acid, iron or iodine.
What to do instead
Build a three-column recall grid: nutrient | function | deficiency sign | rich food sources, and cover one row per nutrient: vitamin A (night blindness, xerophthalmia), thiamine (beriberi), riboflavin (angular stomatitis), niacin (pellagra), vitamin C (scurvy), vitamin D (rickets, osteomalacia), iron (microcytic anaemia), iodine (goitre), calcium (osteoporosis). Recite the grid aloud before the exam and always answer with nutrient plus disease.
Treating the food guide pyramid levels as interchangeable, for example placing pulses and eggs on the cereal level or putting ghee and oil with milk and milk products.
The pyramid is remembered as a picture rather than as a hierarchy of serving counts, so candidates recall the shape but not which foods sit on which tier or how many servings each tier allows.
What to do instead
Redraw the pyramid from memory weekly with serving numbers written on each tier (cereals and millets at the base with the largest number of servings, then vegetables and fruits, then milk/meat/pulses, then fats and sugars at the apex). Then classify twenty mixed foods into tiers without looking, and check against the balanced-diet chart.
Answering a 'plan a day's diet for a 12-year-old girl' question with a menu only, omitting the nutrient calculation, the RDA comparison and the justification of food choices.
Meal planning is studied as a practical skill and candidates reproduce a familiar menu instead of demonstrating the planning process the question rewards: energy and protein targets, meal distribution, inclusion of all five food groups, and cost and seasonality.
What to do instead
Use a fixed answer template: (1) state RDA for energy, protein, calcium and iron for the given age and sex; (2) distribute energy across meals (breakfast about 25%, lunch about 35%, snack about 10%, dinner about 30%); (3) write the menu with household measures; (4) compute energy and protein from a food composition table; (5) comment on adequacy and on any shortfall. Practise the template on three different age groups.
Recommending the same 'diabetic diet' or 'low-salt diet' for every patient in a therapeutic-nutrition question, without modifying consistency, energy density or protein level for the actual condition.
Therapeutic diets are memorised as a list of names (soft diet, bland diet, low-residue diet, renal diet) and candidates match the name to the disease rather than reasoning about which nutrient or texture must change and why.
What to do instead
For each disease, write the modification in a sentence of the form 'restrict/liberalise X because Y': in diabetes, distribute carbohydrate evenly and prefer complex carbohydrate with fibre; in hypertension, restrict sodium and increase potassium; in chronic kidney disease, restrict protein and potassium and control fluid; in diarrhoea, reduce fibre and fat and maintain fluid and electrolytes. Then check the modification against the menu you wrote.
Confusing food adulteration with food spoilage, or giving only one test for a class of adulterants (e.g. saying 'starch is detected by iodine' for every starch-based adulterant without naming the food).
Preservation and adulteration are taught in the same unit and both involve 'something wrong with food', so the distinction between deliberate addition of an inferior substance and natural deterioration is lost.
What to do instead
Learn each common adulterant with its food vehicle and its simple detection test: starch in milk (iodine gives blue-black), metanil yellow in turmeric (hydrochloric acid gives pink), sawdust in chilli powder (floatation in water), chalk in flour, argemone in mustard oil (nitric acid test), water in milk (specific gravity or lactometer). Also write the definition of an adulterant in one line so the conceptual answer is secured first.
Describing nutritional assessment as 'checking the diet' and omitting the four components, or listing anthropometric measurements without stating the cut-offs that classify them.
Assessment is a short topic in the syllabus and candidates skim it, so they recall the word 'anthropometry' but not weight-for-age, height-for-age, weight-for-height, mid-upper-arm circumference or the classification systems (Gomez, Waterlow, IAP grades).
What to do instead
Memorise the framework as ABCD: Anthropometric, Biochemical, Clinical, Dietary. For each, write two concrete measurements and one cut-off: weight-for-age below 60% of reference for severe underweight; MUAC below 13.5 cm indicating severe acute malnutrition in children; haemoglobin below the WHO cut-off for anaemia. Then practise classifying a described child using Gomez and Waterlow.
Naming national nutrition programmes without their target group, delivering agency or key component, for example listing ICDS and mid-day meal without saying who they serve or what they provide.
Programmes are memorised as acronyms from a single revision pass, and the exam asks for specifics such as beneficiaries, services or the year of launch, which acronym-only recall cannot supply.
What to do instead
Build a programme card for each: name, target group, main services, and one distinguishing fact. Cover ICDS (children under six, pregnant and lactating women; supplementary nutrition, immunisation, pre-school education), mid-day meal/PM POSHAN (school children, cooked meal with calorie and protein norms), National Iodine Deficiency Disorders Control Programme (iodised salt), anaemia control (iron-folic acid supplementation), Poshan Abhiyaan and the Public Distribution System. Test yourself by covering the services column.
In practical-work answers, describing a recipe's method but omitting the weighed quantities, the number of portions, the cost per portion or the record-keeping that the practical paper actually assesses.
Candidates revise practical work as cooking rather than as measurement and documentation, so they write narrative steps and lose marks for missing yield, standardisation and survey or record tables.
What to do instead
Write every practical answer in the standard record format: ingredients with weights, number of portions, method in numbered steps, observations on sensory qualities, cost calculation, and nutrient content per portion. For diet surveys, state the method (24-hour recall, food frequency, weighed intake), the sample and the recording table. Rehearse the format on two recipes and one survey before the exam.