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Health: The Ultimate Treasure - Maintain a healthy lifestyle

Grade 8CBSE

Review the key concepts, formulae, and examples before starting your quiz.

🔑Concepts

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Health is defined as a state of complete physical, mental, and social well-being, and not merely the absence of disease.

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A Balanced Diet must contain all essential nutrients like carbohydrates, proteins, fats, vitamins, and minerals in the right proportion. For adolescents, the requirement for FeFe (Iron) increases for blood formation and CaCa (Calcium) for bone development.

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Personal Hygiene involves daily habits like bathing, cleaning teeth, and washing hands with soap to prevent bacterial infections and diseases like TyphoidTyphoid or CholeraCholera.

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Physical Exercise and adequate sleep (approx. 88 hours) are essential for maintaining metabolic rates and mental health.

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Avoidance of Drugs/Tobacco: Adolescence is a vulnerable phase where one must say 'No' to addictive substances as they cause long-term damage to the CNSCNS (Central Nervous System) and lungs.

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Body Mass Index (BMI) is a tool used to estimate whether a person has a healthy body weight for their height.

📐Formulae

BMI=Weight in kg(Height in meters)2\text{BMI} = \frac{\text{Weight in kg}}{(\text{Height in meters})^2}

Daily Energy Balance=Energy Intake−Energy Expenditure\text{Daily Energy Balance} = \text{Energy Intake} - \text{Energy Expenditure}

Total Calories=(4×Proteins in g)+(4×Carbs in g)+(9×Fats in g)\text{Total Calories} = (4 \times \text{Proteins in g}) + (4 \times \text{Carbs in g}) + (9 \times \text{Fats in g})

💡Examples

Problem 1:

Calculate the BMI of a Grade 8 student who weighs 50 kg50\text{ kg} and has a height of 1.6 m1.6\text{ m}. Determine if the student is in the healthy range (Healthy range: 18.518.5 to 24.924.9).

Solution:

BMI=50(1.6)2=502.56≈19.53 kg/m2\text{BMI} = \frac{50}{(1.6)^2} = \frac{50}{2.56} \approx 19.53\text{ kg/m}^2

Explanation:

Since the calculated BMI of 19.5319.53 falls between 18.518.5 and 24.924.9, the student has a healthy weight.

Problem 2:

If a student's recommended daily calorie intake is 2200 kcal2200\text{ kcal} and they consume a breakfast of 450 kcal450\text{ kcal}, a lunch of 850 kcal850\text{ kcal}, and a dinner of 700 kcal700\text{ kcal}, calculate the remaining calories they can consume as snacks using vertical subtraction.

Solution:

First, calculate total consumed: 450+850+700=2000 kcal450 + 850 + 700 = 2000\text{ kcal}. Then subtract from total limit: 2200−2000200\begin{array}{r} 2200 \\ - 2000 \\ \hline 200 \end{array}

Explanation:

By subtracting the total calories consumed from the daily limit, we find the student can still consume 200 kcal200\text{ kcal}.

Problem 3:

A snack contains 5g5\text{g} of protein, 10g10\text{g} of carbohydrates, and 2g2\text{g} of fat. Calculate the total energy provided by this snack.

Solution:

Energy=(5×4)+(10×4)+(2×9)\text{Energy} = (5 \times 4) + (10 \times 4) + (2 \times 9) Energy=20+40+18=78 kcal\text{Energy} = 20 + 40 + 18 = 78\text{ kcal}

Explanation:

Proteins and Carbohydrates provide 4 kcal/g4\text{ kcal/g} each, while fats provide 9 kcal/g9\text{ kcal/g}.

Maintain a healthy lifestyle Class 8 Notes & Examples