[Rhythm of Life]

Nutrition:

•Energy Output

Basal metabolism: minimum energy expended in a fasting state

a.60% to 70% of total kcalorie expenditure

b. Basal metabolism lowered 10% to 20% during low-kcalorie intake (150 to 300 kcals per day)

c. Basal metabolic rate declines about 1 - 2% each decade past age 30

•Basal Metabolic Rate

•Factors that influence basal metabolism

1) Lean body mass

2) Amount of body surface

3) Gender

4) Body temperature

5) Thyroid hormone

6) Nervous system activity

7) Pregnancy

8) Caffeine and tobacco use

•Other Energy Expenditures

•Energy for physical activity

- 25% to 40% of total energy output

•Thermic effect of food (TEF)

- 5% to 10% of total kcalories eaten

•Thermogenesis or Non-exercise activity thermogenesis (NEAT)

- Increase in nonvoluntary physical

activity like shivering, fidgeting…

- Accounts for very small portion of

energy use

•Measurement of energy use

•Direct calorimetry

•Indirect calorimetry

•Estimate Energy Requirement

•Harris Benedict Formula for Women:

•BMR = 655 + (9.6 X weight in kilos) + (1.8 X height in cm) - (4.7 X age in years).

•Notes:
1 inch = 2.54 cm.
1 kilogram = 2.2 lbs.

•BMR x Activity factor = EER

•Estimate Energy Requirement

•Harris Benedict Formula for Men

•BMR = 66 + (13.7 X weight in kilos) + (5 X height in cm) - (6.8 X age in years)

•Notes:
1 inch = 2.54 cm.
1 kilogram = 2.2 lbs.

•BMR x Activity factor = EER

•BMI

•BMI equals a person's weight in kilograms divided by height in meters squared. (BMI=kg/m2)

•BMI

•BMI should not be applied to

1) Children or adolescents still growing

2) Frail older people

3) Pregnant and lactating women

4) Highly muscular individuals

•Body Fat

•Desirable amount of body fat

1) Women: 21% to 35%

2)Men: 8% to 24%

•Different types of fat distribution

1.Apple

2.Pear

•Two Types of Body Fat

•Apple Shape

•Upper body (android) obesity

1) Related to heart disease, high blood pressure, and type 2 diabetes

2) Encouraged by alcohol intake, smoking and testosterone

•Pear Shape

•Lower body (gynoid) obesity

1) Fat resists being shed

2)Encouraged by estrogen and

progesterone

3) Waist circumference > 40" for men; >35" for women

4) Along with BMI >25 significant health risk

•Body Fat

•Body fat differs between men and women due to difference in: (1) hormones, (2) body structure.

•Two types of body fat :

1.Essential: necessary for body functioning, max 7% in men and max 15% in women

2.Storage: remaining fat in the body

•Measures of Body Fat

•Different techniques:

1.Underwater weighing

2.Skinfold measurement

3.Bioelectrical Impedance Analysis (BIA)

4.Soft-Tissue Roentgenogram

5.Circumference measures

6.Dual Energy X-ray Absorptometry(DEXA)

•Underwater weighing

•A method for determining the lean body mass. This method weighs a person underwater by measuring the amount of water displaced when a person completely submerged. This method is one of the more accurate ones. However, it is generally done in special research facilities, and the equipment is costly. Also called hydrostatic weighing.

•Skinfold Measurement

•Fold of body skin and fat at various points are grasped between thumb and forefinger and measured with calipers

•Bioelectrical Impedance Analysis (BIA)

•Electrical currents are passed through fat and lean tissue

•The body’s ability to conduct an electrical current reflects the total amount of water in the body

•The more water, the more muscle and lean tissue

•Soft-Tissue Roentgenogram

•Injecting a radioactive substance into the body and allowing this substance to penetrate lean tissue, then by imaging distinctions between fat and lean tissue can be done

•Dual Energy X-ray Absorptometry (DEXA)

•A technique for scanning bone mass density (BMD) and lean tissue.

•Based on two X-ray beams, each with different energy levels (high and low)

•The amount of x-rays that pass through the fat and lean tissues is measured for each beam.

•Based on the difference between the 2 beams, the bone density or lean tissue can be measured.

•Factors Contributing to Obesity

1.Environmental and Lifestyle

2.Heredity

3.Malfunction of organs regulating food intake

4.Developmental

5.Psychological

•Gene & Obesity

•Genetic background accounts for up to 70% of weight differences between people

Chances of becoming obese

1) 10% if no obese parents

2) 40% if one obese parent

3) 80% if two obese parent

•Genes determine metabolic rate, fuel use, brain chemistry

•Environment & Obesity

•Environmental factors can impact weight

1) High-fat diets and inactivity promote weight gain

2) Poverty can contribute to obesity

3)Inactivity, stress, boredom, and large pregnancy weight gain are associated with obesity

•Malfunction of Organs

•The hypothalamus regulates appetite

•Adaptive Thermogenesis: thin people send more effective messages to the hypothalamus

•Satiety: to be satisfied with nutritional needs and the stomach signals “no more”

•Developmental Factor

•Hyperplasia: condition where a person has an excessive number of fat cells

•Increasing number of fat cells:

1.Last few weeks before birth

2.First year of life

3.Ages 9-13

4.Pregnancy

•The number of fat cells stay constant, even through weight loss

•Developmental Factor

•The Set Point Theory: person’s body has a set point of weight which it is programmed to be comfortable

•Plateau: The point in a weight loss program that dieter finds it difficult to lose more weight

•Inactive thyroid: just 2-5% of obese people

•Wt. loss & lifestyle changes

•Characteristics of a sound weight loss plan

1. Control Calorie intake, slow steady loss

2. Increase physical activity

3.Maintenance plan for life long changes

•The main key to weight loss: Controlling calorie intake

•Managing Your Weight

•Best Weight management programs:

1.Healthy Eating

2.Regular Exercise

•Two ways to lose weight:

1.Decrease calorie intake

2.Burn more calorie

•Fat Loss

•1 pound fat = 3,500 calories

•Losing 1 pound/ week means burning 3,500 calories in a week

•500 calories/day = 200 diet + 300 exercise

•Changing Eating Habits

•Avoid triggers

•Change the negative thoughts

•Eat more frequently during the day

•Small portions

•Eat slowly

•Allocate specific eating time

•Drink plenty of water

•Exercise in Weight Management

•Amount of calories spent during exercise depends on:

1.Duration

2.Intensity

3.Person’s weight

4.Type of exercise

Poor diet and sedentary lifestyle are risk factors for disease

Diet plays a role in 6 of the 10 leading causes of death in the US

Essential Nutrients

1.Proteins

2.Carbohydrates Calories

3.Fats

4.Vitamins

5.Minerals No calories

6.Water

Essential Nutrients’ Functions

a. Provide energy expressed in kilocalories (kcal) also called energy yielding nutrients

b. Important for growth, development and maintenance

c. Regulate body processes

Energy Production:

Dietary Guidelines

Total calorie intake:

1.55-60% from CHO

2.10-15% from proteins

3.25-30% from fat

Obtaining Essential Nutrients

Water:

1.50-60% of our total body weight

2.Dehydration can cause death

3.We need 6-8 glasses of water a day

Protein

Protein

1.Major components of every cell

2.Made from Amino acids

3.1 gram protein = 4 calories

4.Two different types of amino acid groups:

1) Essential

2) Non essential

Protein

Two different types of proteins:

1) Complete

2) Incomplete

Protein functions in the body:

1.Tissue repair

2.Formation of hormones

3.Antibody production

Protein

Combination of plant and animal foods make a rich source of complete protein

Main plant protein sources are:

1.Nuts & seeds

2.Legumes

3.Grains

Carbohydrate

Carbohydrate (CHO):

Contains Carbon, Hydrogen and Oxygen

1 gram CHO = 4 calorie

Two different types of CHO:

1.Simple

2.Complex 1. Starch

2. Fiber or cellulose

Carbohydrate

CHO works as a energy source for the body

Simple CHO has negative effect on exercise performance

Complex CHO (starch) can increase exercise performance if eaten at a right time prior to exercise

Fiber

Fiber:

Two different types of fiber:

1.Soluble: partially soluble in water (decrease risk of CVD and high cholesterol levels)

2.Insoluble: completely insoluble in water (decrease risk of cancer)

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Fiber

Fiber

nBenefits of fiber intake:

1.Lowers risk of diabetes

2.Lowers risk of heart disease

3.Lowers risk of breast cancer

4.Protection against obesity

5.Protection against constipation

Fiber

Recommendations for fiber intake:

1.20-30g/ day

2.Eat variety of foods

3.Eat at least 5 servings of fruits and vegetables a day

4.Eat less processed foods

5.Drink plenty of water

6.Eat fruits’ skin

Fat

Fats:

1 gram fat = 9 calorie

Function of fat:

1.Energy source

2.Cell function

3.Maintain body temperature

4.Organ insulation

Fat

Two different types of fat in the body:

1.Triglycerides (TG): 95% of body fat

2.Cholesterol 1. LDL

2. HDL

Obtaining Essential Nutrients

Vitamin

Vitamins:

No calorie nutrient, organic compounds

Two types of vitamins:

1.Water soluble: ADEK

2.Fat soluble: BC

Vitamin

Functions of vitamins:

1.Promote growth

2.Maintain life and health

3.Necessary for different metabolism

Mineral

Minerals:

No calorie nutrient, inorganic compounds

Two types of minerals:

1.Macrominerals

2.Trace minerals

Sodium

Sodium:

Regulation of body fluid and blood pressure

Recommendation: 2,400mg / day

Most Americans consume 6,000 to 12,000 mg/day

High sodium intake results in hypertension

Calcium

Recommendation: 1,000- 1,200 mg/day

Functions:

1.Strong bones, teeth

2.Muscle contraction

3.Blood clotting

4.Nerve impulse transmission

5.Regulating heartbeat and fluid balance within cells

Calcium

Enhancers:

1.Vitamin D

nInhibitors:

1.Oxalate

2.Phytate

3.Caffeine

4.Phosphoric acid

Iron

Recommendation: 18 mg/day for women and 10 mg/day for men

Anemia: inability to produce hemoglobin

Hemochromatosis or high iron levels in plasma, which can cause heart disease and liver disorders and poisoning in children

The Medicinal Value of Food

Eating the right food not only prevents the disease but also cure diseases

Right diet can cure hypertension, diabetes and hypercholesterolemia

Antioxidants found in fruits and vegetables:

1.Vitamin C

2.Vitamin E

3.Lycopene

4.Lutein

5.Folic acid or folate

Folic Acid

Between the 17th and 30th day after conception, the neural tube forms in the embryo and then closes. The neural tube later becomes the baby’s spinal cord, spine, brain, and skull. A neural tube defect (NTD) occurs when the neural tube fails to close properly, leaving the developing brain or spinal cord exposed to the amniotic fluid. The two most common neural tube defects are anencephaly and spina bifida.

V. Gender & Nutrition

Men burn more calories than women

For every three servings of fruits and vegetables per day men can expect a 22% lower risk of stroke

Diets high in fruits and vegetables may lower the risk of lung cancer in smokers from 20 times the risk of non-smokers.

Water

•Water is a solvent dissolving many body components

•50% to 70% of the body's weight (about 10 gallons)

•Lean tissue: --------------water

•Fat tissue: ------------------water

•Humans can survive only a few days without water

•Intracellular and extracellular fluid
–Ion or electrolyte concentrations control the amount of water in intracellular and extracellular fluid

»Ions are electrically charged molecules that attract water

»Chloride, potassium, sodium, phosphate magnesium and calcium are all ions

•Temperature Regulation
•Perspiration

–Evaporation releases heat and cools the skin

–Perspiration is the primary way to prevent body heat from rising

•Waste Excretion

•Most unused substances in the body can dissolve in water and exit in the urine

–Urea is the product created to excrete excess Nitrogen and sodium

–Generally, the amount of urine we excrete is determined by the amount of sodium and protein we need to excrete

•Healthy urine output: 1 liter or more per day

–Less than 500 milliliters (2 cups) forces kidneys to excessively concentrate the urine

–Observe the color of urine to determine if it is too concentrated

–Urine should be clear or pale yellow

–Heavy ion concentration in urine increases risk of kidney stones

•Other functions

•Two other functions of water:

•Helps form lubricants found in knees and other body joints

•Basis for saliva, bile, and amniotic fluid

•How much water do we need per day?

•Adequate Intake for total water intake: including fluid from food and beverages

–Women: 2.7 liters (11 cups)

–Men: 3.7 liters (15 cups)

•Fluid Intake aside from food should be

–Women 2.2 L (9 cups)

–Men 3 L (11cups)

–Includes juice, soda, coffee, tea

–Coffee, tea and soda (?)

•Water Loss

–Urine production: 500 or more milliliters

–Lungs: 250 - 350 milliliters

–Colon: 100 - 200 milliliters

–Skin: 450 - 1900 milliliters

–Above values are estimates affected by altitude, caffeine, alcohol, and humidity

•Thirst

•Athletes

–Weigh before and after training sessions to determine their rate of water loss and thus water needs

–Drink 3 cups of water per pound lost

•Others who have greater water needs

–Ill children

–Older persons

–Infants

•Ignoring Thirst Mechanism

–Body conserves water

–Antidiuretic hormone released by pituitary gland forcing kidneys to conserve water by reducing urine output

–As blood volume decreases, blood pressure falls triggering release of aldosterone which signals kidneys to retain sodium and therefore water is also retained

–Water losses continue via feces, skin and lungs

–Eventually the body becomes dehydrated

...More to be added