Obesity
Obesity is excess body fat that harms health; for Indian adults, BMI 25 or more. Treat it with a steady energy deficit, more activity and lasting habit change.
At a glance
Worked example: energy for weight loss
Mr. Ravi is 170 cm tall, weighs 85 kg, is sedentary and usually eats about 2,500 kcal a day. Find his BMI, IBW and energy prescription, and estimate his weekly weight loss.
- Height² = 1.70 × 1.70 = 2.89 m². BMI = 85 ÷ 2.89 = 29.4 kg/m²: obese by the Asian Indian cut-off.
- IBW (Broca's) = 170 − 100 = 70 kg.
- Energy for a sedentary overweight adult = 20-25 kcal/kg IBW. Take 25: 25 × 70 = 1,750 kcal a day.
- Daily deficit = 2,500 − 1,750 = 750 kcal. Weekly deficit = 750 × 7 = 5,250 kcal.
- 1 kg of body fat stores about 7,700 kcal. Weekly loss = 5,250 ÷ 7,700 = 0.68 kg, about 0.7 kg a week.
- To reach 70 kg he must lose 15 kg: 15 ÷ 0.68 = about 22 weeks (5 months).
BMI 29.4 (obese); IBW 70 kg; prescribe about 1,750 kcal a day; expected loss about 0.7 kg a week. Real loss slows over time as the body adapts.
Dietary principles
| Nutrient | Recommendation | Why |
|---|---|---|
| Energy | Deficit of 500-1,000 kcal a day, or 20-25 kcal/kg IBW; usually 1,000-1,200 kcal for women and 1,200-1,600 kcal for men (NIH 1998; newer US guidance says 1,200-1,500 and 1,500-1,800) | Gives a safe loss of 0.5-1 kg a week |
| Protein | About 1 g/kg IBW (15-20% of energy): dal, sprouts, curd, egg white, fish, chicken, paneer from toned milk | Keeps you full and protects muscle |
| Fat | 20-25% of energy; little saturated fat; no trans fat | Fat gives 9 kcal per gram, more than twice carbohydrate |
| Carbohydrate | Complex, high-fibre, low-GI; cut sugar, sweets and sugary drinks | Steadier blood sugar and less hunger |
| Fibre | 25-40 g a day: whole grains, millets, pulses, vegetables, fruits | Adds bulk with few calories |
| Fluid | Water, buttermilk, lemon water without sugar | Sugary drinks and juices add calories without fullness |
| Meal pattern | Regular meals, no skipped breakfast, small plates, eat slowly | Prevents overeating later in the day |
| Activity and behaviour | At least 150 minutes of moderate activity a week, more for weight loss; food diary; good sleep | Raises energy output and keeps the weight off |
Foods and a sample one-day low-calorie menu
| Item | Details |
|---|---|
| Include | Millets (ragi, jowar, bajra), whole wheat, oats, dals, sprouts, green leafy vegetables, salads, guava, orange, papaya, toned milk, curd, egg white, fish, chicken (no skin) |
| Avoid or limit | Fried snacks (samosa, bajji, chips), sweets, bakery items, sugary drinks and juices, ghee and butter, coconut-rich curries, alcohol, large portions of rice |
| Early morning | Tea or coffee with toned milk, no sugar |
| Breakfast | Ragi dosa (2) or vegetable oats upma with mint chutney |
| Mid-morning | Guava or an orange; buttermilk |
| Lunch | Phulka (2) or 1 cup rice, dal, keerai poriyal, large salad, curd |
| Evening | Sprouts chaat with cucumber and tomato; green tea |
| Dinner | Jowar roti (2), grilled fish or paneer tikka (toned-milk paneer), vegetable soup |
In the clinic, measure waist as well as BMI; many Indian patients have a normal BMI but a large waist. A realistic goal of 5-10% weight loss already lowers blood sugar and blood pressure.
2 marks: “Give the BMI cut-offs for overweight and obesity in Asian Indians.” Overweight 23-24.9 kg/m²; obese 25 kg/m² or more.
5 marks: “What are the causes and complications of obesity?” Causes: energy imbalance, genes, inactivity, diet, hormones, drugs. Complications: diabetes, hypertension, heart disease, fatty liver, gallstones, arthritis, PCOS, cancers.
10 marks: “Discuss the classification, causes and dietary management of obesity. Plan a one-day menu.” Define with BMI and waist cut-offs, types, causes, complications, energy calculation, principles table, foods, menu, exercise and behaviour change.
500 a day takes about half a kilo a week. Indian cut-offs: 23 overweight, 25 obese; waist 90 men, 80 women.