Energy nutrition

Lecture Overview

  • Lecture 5 covers:

    • Energy balance

    • Food labels

    • Energy needs throughout a lifetime

Understanding Energy

  • Energy is synonymous with "calories."

    • Caloric burn occurs through:

      • Basic bodily functions (breathing, digestion)

      • Daily activities (varying based on body size and activity level)

      • Those with physically active lifestyles burn more calories.

Energy Balance

Definition

  • Energy balance is the relationship between energy intake (calories consumed) and energy expenditure (calories burned).

Types of Energy Balance

  • Energy in vs. Energy out

    • Equal energy input and output: weight remains stable.

    • More energy in than out: leads to weight gain.

    • More energy out than in: results in weight loss.

  • Daily fluctuations in energy balance are normal; complete daily balance is not necessary.

Components of Energy Expenditure

  • Basal Metabolism

    • Accounts for ~60-70% of total energy use.

    • Necessary for sustaining heartbeats, respiration, body temperature.

  • Physical Activity

    • Varies greatly among individuals.

    • Lack of activity is a major contributor to obesity.

  • Thermic Effect of Food (TEF)

    • Energy required to digest, absorb, and metabolize nutrients (5-10% of total energy).

    • Higher for carbohydrates and proteins compared to fats.

Managing Energy Out

  • Recommendations for physical activity:

    • Adults: Minimum of 30 minutes most days of the week.

    • Children: Minimum of 60 minutes of activity daily.

    • Activities can be broken into shorter segments.

Caloric Intake & Expenditure Examples

Reducing ENERGY IN

  • Actions to cut 150 calories:

    • Drink water instead of soda.

    • Choose smaller sides or healthier alternatives (e.g., egg-white omelet, canned tuna in water).

Increasing ENERGY OUT

  • Activities to burn an additional 150 calories:

    • Shoot hoops for 30 minutes.

    • Walk two miles in 30 minutes.

    • Engage in gardening for 30 minutes.

    • Bike ride for 30 minutes.

    • Dance for 30 minutes.

Body Composition and Measurement

  • Methods to Measure Body Fat:

    • Fatfold measures

    • Hydrodensitometry

    • Bioelectrical impedance

    • Air displacement plethysmography

    • Dual-energy X-ray absorptiometry (DEXA)

  • Distribution of Body Fat:

    • Central obesity (abdominal fat) linked to higher risk of diseases such as Type 2 Diabetes, hypertension.

    • Waist circumference indicators:

      • Women > 35 inches

      • Men > 40 inches

Nutrition Facts & Food Labeling

Understanding Nutritional Labels

  • Nutritional facts to consider:

    • Serving size

    • Calories and calorie source breakdown

    • Daily Values, e.g., total fat, saturated fat, sodium, carbohydrates, vitamins, etc.

  • Guides to % Daily Values:

    • 5% DV or less = low

    • 20% DV or more = high

Sugar and Nutrient Limits

  • Added sugars should not be listed among the first ingredients.

  • Nutrient comparisons useful for making healthier choices.

Lifecycle Nutritional Needs

Nutritional Stages

  • Lifecycle stages include:

    • Young adulthood (19-30 years)

    • Middle adulthood (31-50 years)

    • Older adulthood (51-70 years)

    • Elderly (beyond 70 years)

Pregnancy Nutritional Needs

  • Increased nutrient and energy requirements essential for:

    • Fetal growth

    • Maternal health changes

  • Approximately 300 extra calories needed during the second and third trimesters.

  • Important to ensure adequate protein intake, ideally at least 60g/day.