9 min readConcept sheetCommon 10-mark case; Asian BMI cut-offs and the 500 kcal deficit are standard viva points

Diet in obesity

Obesity diet: a 500-1000 kcal daily deficit for 0.5-1 kg loss a week, adequate protein, high fibre, low fat and sugar, plus activity and habit change.

Asian BMI cut-offsNormal 18.5-22.9 (18.0-22.9 in the Indian consensus); overweight 23-24.9; obese 25 or more (WHO Asia-Pacific; Indian consensus 2009)

Waist (Asian Indians)Abdominal obesity at 90 cm or more in men and 80 cm or more in women

Energy deficit500-1000 kcal a day gives about 0.5-1 kg loss a week (1 kg fat ≈ 7700 kcal); diets below about 1000 kcal need medical supervision

Protein1.0-1.2 g/kg IBW to protect muscle and improve fullness

Aim and principles of the diet

Aim: To plan, prepare and calculate a weight-reducing diet for an obese woman. Principles: Obesity is excess body fat. In Asian Indians it is diagnosed at a BMI of 25 or more (overweight 23-24.9), and abdominal obesity at a waist of 90 cm or more in men and 80 cm or more in women (Indian consensus 2009). A 2025 Indian revision (Misra and colleagues) treats a BMI above 23 as obesity and grades it into stages by waist size and health problems; most textbooks still use the 2009 cut-offs. Obesity raises the risk of diabetes, high BP, heart disease and joint pain. The diet creates an energy deficit of 500-1000 kcal a day, which gives a safe loss of about 0.5-1 kg a week, because 1 kg of body fat stores about 7700 kcal. Diets below about 1000 kcal need medical supervision. Protein is adequate to slightly high (1.0-1.2 g/kg IBW) to protect muscle and keep the patient full. Fat is low (20-25% of energy), because fat gives 9 kcal per gram: fried foods, ghee, bakery items and large amounts of nuts are cut. Carbohydrate comes from whole grains, millets and pulses (low glycaemic index, high fibre); sugar, sweets and sweetened drinks are avoided. Fibre (25-40 g or more) and low-energy, high-volume foods (vegetables, salads, clear soups, buttermilk) give fullness. Regular small meals, never skipping breakfast, and eating slowly prevent overeating. Physical activity (at least 150 minutes of moderate activity a week) and behaviour change (food diary, smaller plates, enough sleep) keep the weight off.

Nutrient prescription: Mrs. O, 35 y, 160 cm, 80 kg, waist 96 cm, sedentary

Nutrient	Prescription	Basis and source
BMI and IBW	BMI 31.3; IBW 54 kg	80 ÷ 2.56; (160 − 100) × 0.9
Energy	About 1400 kcal	25 kcal/kg IBW × 54 = 1350 (Indian texts use about 20-25 kcal/kg IBW); also usual 2000 − 600 kcal deficit
Protein	About 60 g	1.1 g/kg IBW (range 1.0-1.2 g/kg)
Fat	20-25% of energy (about 30-40 g); about 15 g oil	1400 × 0.20 ÷ 9 = 31 g; 1400 × 0.25 ÷ 9 = 39 g
Carbohydrate	50-55% of energy (about 175-195 g), mostly complex	No added sugar
Fibre	25-40 g or more	High-volume, filling foods
Expected loss	About 0.5 kg a week	600 kcal × 7 = 4200 kcal ÷ 7700 kcal per kg

Foods to include and avoid

Food group	Choose	Avoid or limit
Cereals	Whole wheat, ragi, oats, broken wheat, hand-pounded rice in measured portions	Maida, bakery items, large rice portions, fried tiffins (puri, vada)
Pulses and protein foods	Dals, sprouts, chilla, egg white, fish, skinless chicken, low-fat paneer	Fried meat, fatty mutton, full-fat paneer in large amounts
Milk	Double-toned or skimmed milk, low-fat curd, buttermilk	Whole milk, cream, khoa sweets, sweet milkshakes
Vegetables	Plenty: greens, gourds, cucumber, cabbage, salads, clear soups	Chips, vegetables fried in batter
Fruits	Guava, papaya, orange, apple (whole fruit)	Fruit juices; mango, banana and dried fruits in large amounts
Fats and sugar	Measured oil (about 3 tsp a day)	Ghee, butter, vanaspati, sugar, jaggery, sweets, soft drinks, alcohol

Sample one-day menu: weight reduction (Mrs. O)

Time	Menu	Approx. amount (raw)
6.00 am	Warm water with lemon, no sugar	1 glass
7.00 am	Tea without sugar	Double-toned milk 100 mL
8.00 am	Moong dal chilla (2) with mint chutney	Moong dal 40 g, vegetables 50 g, oil 4 g
11.00 am	Buttermilk and guava	Buttermilk 200 mL; guava 100 g
1.00 pm	Phulka (2), rice, tur dal, greens poriyal, salad, low-fat curd	Atta 50 g; rice 65 g; tur dal 20 g; greens 100 g, oil 4 g; raw vegetables 100 g; low-fat curd 100 g
4.00 pm	Tea without sugar, sprouts salad	Double-toned milk 100 mL; whole green gram 25 g, vegetables 25 g
7.30 pm	Clear vegetable soup, phulka (2), vegetable sabzi, egg-white bhurji (or 30 g low-fat paneer)	Vegetables 50 g; atta 50 g; vegetables 150 g, oil 7 g; 2 egg whites
9.00 pm	Papaya	100 g

Worked calculation: Mrs. O's weight-reducing diet

Problem

Mrs. O, 35 years, 160 cm, 80 kg, waist 96 cm, is a sedentary homemaker. Her diet history shows about 2000 kcal a day. Find her BMI, IBW, energy and protein, and check the menu.

Working

BMI = 80 ÷ (1.6 × 1.6) = 80 ÷ 2.56 = 31.3: obese by the Asian cut-off of 25; waist 96 cm (above 80 cm) shows abdominal obesity.
IBW = (160 − 100) × 0.9 = 54 kg.
Energy = 54 kg × 25 kcal/kg = 1350, rounded to 1400 kcal. Check: usual 2000 kcal − 600 kcal deficit = 1400 kcal. 600 × 7 = 4200 kcal a week ÷ 7700 kcal per kg of fat = about 0.55 kg loss a week.
Protein = 54 kg × 1.1 g/kg = 59.4, about 60 g, to protect muscle and keep her full.
Approximate values used (kcal and g protein per 100 g raw unless stated; rounded from Indian food composition tables, mainly IFCT 2017 and the older Nutritive Value of Indian Foods; a few, such as toned milk, are estimates): double-toned milk 45 and 3 per 100 mL; moong dal 325 and 24; mixed vegetables 30 and 1.5; oil/ghee 900; buttermilk 15 and 0.8 per 100 mL; guava 50 and 1; atta 320 and 10.5; rice 355 and 8; tur dal 330 and 22; greens 35 and 3; low-fat curd 45 and 3; whole green gram 325 and 23; egg white 17 kcal and 3.5 g per piece; papaya 35 and 0.5.
Cereals (atta 100 g, rice 65 g): 550.8 kcal, 15.7 g protein, 13.0 g fibre.
Pulses (moong dal 40 g, tur dal 20 g, whole green gram 25 g): 277.3 kcal, 19.8 g protein, 9.7 g fibre.
Milk and milk products (double-toned milk 200 mL, buttermilk 200 mL, low-fat curd 100 g): 165.0 kcal, 10.6 g protein, 0.0 g fibre.
Egg white (2 egg whites): 34.0 kcal, 7.0 g protein, 0.0 g fibre.
Vegetables (mixed vegetables 375 g, greens 100 g): 147.5 kcal, 8.6 g protein, 15.3 g fibre.
Fruits (guava 100 g, papaya 100 g): 85.0 kcal, 1.5 g protein, 8.0 g fibre.
Oil and ghee (oil/ghee 15 g): 135.0 kcal, 0.0 g fibre.
Energy = 550.8 + 277.3 + 165.0 + 34.0 + 147.5 + 85.0 + 135.0 = 1394.6 kcal.
Protein = 15.7 + 19.8 + 10.6 + 7.0 + 8.6 + 1.5 = 63.2 g.
Fibre = 13.0 + 9.7 + 15.3 + 8.0 = 46.0 g.
Compare with the prescription: energy 1394.6 ÷ 1400 × 100 = 100%; protein 63.2 ÷ 60 × 100 = 105%.
Fibre values used (g per 100 g raw, approximate): atta 11, rice 3, dals 9, whole green gram 17, vegetables 3, greens 4, guava 6, papaya 2. About 46 g fibre from plenty of vegetables keeps the low-energy diet filling.
Each group is rounded to one decimal and the totals are the sums of those rounded figures; all values are approximate.

Answer

BMI 31.3, IBW 54 kg; prescription about 1400 kcal and 60 g protein. The menu gives about 1395 kcal (100%), 63 g protein (105%) and about 46 g fibre, for about 0.5 kg loss a week.

Preparation and serving tips, and result

Use a smaller plate: half vegetables and salad, a quarter cereal, a quarter dal or protein food.
Measure oil with a teaspoon (3 teaspoons a day here); dry-roast, steam, grill or pressure-cook.
Serve soup or salad first to fill the stomach, and eat slowly.
Cut sugar in tea gradually; avoid juices, sweets and fried snacks.
Keep a food and activity diary; weigh once a week at the same time on the same scale.
Result: The weight-reducing diet gives about 1395 kcal, 63 g protein and about 46 g fibre, meeting Mrs. O's prescription and allowing about 0.5 kg loss a week.

In the diet kitchen

In the diet kitchen, a weight-reducing tray is planned with measured portions: phulka without ghee, dal and vegetables cooked with a teaspoon of oil, buttermilk instead of a sweet. Staff canteens can use the same ideas: a fruit and salad counter, steamed or baked snacks, and double-toned milk in tea.

Exam angle

Short answer: “Give the BMI cut-offs for Asian Indians.” Normal 18.5-22.9 (18.0-22.9 in the Indian consensus); overweight 23-24.9; obese 25 or more (WHO Asia-Pacific; Indian consensus 2009).

Short answer: “How much weight loss does a 500 kcal daily deficit give?” 500 × 7 = 3500 kcal a week; 1 kg body fat ≈ 7700 kcal, so about 0.45-0.5 kg a week.

Essay: “Plan a weight-reducing diet for an obese woman and calculate its nutritive value.” BMI and waist; IBW; energy by kcal/kg IBW and by deficit; protein 1.0-1.2 g/kg; low fat, no sugar, high fibre; foods to choose and avoid; Indian menu with soups, salads, sprouts and buttermilk; calculation; result; tips on portion plates, activity and a food diary.

Remember it

'Less in, more out, slow and steady': 500-1000 kcal less a day, 150 minutes of activity a week, 0.5-1 kg loss a week.