A Naval Aviation Survival Training Program Subject Matter Experts Brief

NUTRITIONNUTRITION

ENABLING OBJECTIVES

• Identify nutrients in food

• Identify caloric values

• Explain safety in weight control

NUTRIENTS

NUTRITION

• Nutrition is the study of nutrients and how the body uses them.

• Six nutrients in food:– carbohydrates– protein– Fat

– vitamins– minerals– water

Calorie Containing Nutrients

CARBOHYDRATE

• Carbohydrates are converted into glucose, provide energy, and are the main fuel source within the body.

• 4 calories per gram

• Stored as glycogen with excess being converted to body fat.

• 45-65% of total caloric intake for normal adults (endurance athletes may need more)

CARBOHYDRATE

• Two types– Simple carbohydrates

• Derived from fruits and sugars.

– Complex carbohydrates • Derived from vegetable, grains,fruits, and beans.

GLYCEMIC INDEX

• Measure of the rise in blood sugar after consuming food.

• Sharp rise in blood sugar is not desirable.

• Most of your carbohydrates should come from low glycemic index sources if possible.

GLYCEMIC INDEX

CARBOHYDRATESDuring/After Exercise

• Fully carb loaded prior (500g on day before)

• 60g/hour to maintain performance

• 100-300 g immediately after (within 1.5 hours)

• Carbohydrates spare protein!

PROTEIN

• What does protein do?– Builds and repairs body tissues, and if not supplied in

the diet, malnutrition will result.– Form enzymes, hormones and antibodies. – Plays a structural role in all body tissue.

• 15% of total caloric intake (4 cal/gm)• Can be found in meat, eggs, fish, poultry, beans, peas,

nuts, and dairy products.

FAT

• Functions of fat:– Lines and insulates neurons (nerves) in the

brain and body. – Carrier of certain vitamins (fat soluble

vitamins).– Fat deposits protect and cushion the body.– Insulates the body against loss of heat.

• < 30% of total caloric intake• 9 calories per gram

THREE TYPES OF FAT

• Poly-unsaturated: – Fish, oils (corn, sunflower)

• Mono-unsaturated:– Oils (olive, peanut, canola), nuts

• Saturated: – Meats and dairy products, tropical oils (coconut

and palm oil), solid at room temperature. Tends to raise blood cholesterol.

– Should not account for more than 10% of total fat intake for the day.

• Partially hydrogenated?

FAT

• Hydrogenation– A process by which liquid oils (poly or mono-

unsaturated) are turned into solid fats. Process for making margarine and shortening.

• Reducing Fat – Eat only lean cuts of beef. Boil or bake your food

and try to avoid fried foods. – Choose low fat milk or skim. – Minimize the use of cooking oils, reduce salad

dressing, and limit the intake of nuts and peanut oil.

MACRONUTRIENT %

• 40/30/30: Zone

• Low Carb: <40% carb– 300g +1200g = 1500g or 3.5lbs

• Low Fat: <30% fat, 45-65% carbohydrates, 10-25% protein

CHOLESTEROL

• Should be limited to 300mg per day.

• Found in rich foods:– Liver– Organ meats– Egg yolk– Red meats

• Beware of cholesterol content in foods and adjust your diet accordingly.

VITAMINS

• An organic substance found in food that is essential in small quantities for growth, health and life.

• Deficiency of vitamins causes diseases sugch as scurvy (Vitamin C), beriberi (Vitamin B1), and rickets (Vitamin D).

• Vitamins are needed for vision, DNA formation, bone ossification, red blood cell formation, maintenance of skin, blood clotting, and metabolism of carbohydrates, proteins and fats.

TYPES OF VITAMINS

• Water-soluble – Vitamins in excess are generally excreted in the urine. The

water-soluble vitamins are B complex and C.

• Fat-soluble – Vitamins are stored in the body tissue and are not normally

excreted in urine. The fat-soluble vitamins are A (includes Beta-Carotene), D (can be synthesized by sun), E (no toxicity symptoms), K (helps blood clotting). May require protein carriers.

• Note: The body does not store water-soluble vitamins in appreciable amounts, while fat-soluble vitamins are stored.

MINERALS

• The body is composed of at least 31 known chemical elements, of which 24 are considered to be essential for sustaining life.

• They are obtained from food and water.• As in the case of vitamins, many people self-

diagnose possible mineral deficiencies and take unnecessary mineral supplements.

MINERALS

• Certain populations may need mineral supplements.- Fluoride: Infants and children- Calcium: Pregnant women and elderly- Iron: Pregnant women

• Many health food stores market vitamins/minerals for sale with fraudulent nutritional claims BE CAUTIOUS!

WATER

• The body is approximately 60% water.

• Muscle tissue is ~ 75% water.

• It is the major component of plasma and the major transportation mechanism in the body.

• Body temperature regulation (sweating)

TYPICAL FLUID LOSSES

Event Duration (hrs) Fluid Loss (qts)

BUD/S 12 10

Working in heat 8 6.5

Cold Water Dive 6 1.5

MOPP Gear OPS 4 6.5

SDV Ops 3-7 2

5.5 Mile Swim in wet Suit

4 3.2

Triathlon (IM) 12 10

Marathon 3.5 3.5

DEHYDRATION AND EXERCISE• 0% normal heat regulation and

performance

• 1% thirst is stimulated, heat regulation during exercise is altered, performance begins to decline

• 2% further decrease in heat regulation, increased thirst, worsening performance

• 3% more of the same

• 4% exercise performance cut by 20 - 30%

• 5% headache, irritability, "spaced-out" feeling, fatigue

• 6% weakness, severe loss of thermoregulation

• 7% collapse is likely unless exercise is stopped

Tips• Do not rely on

thirst.• Anticipate fluid

losses.• Check urine color.• Drink regularly.• Weigh before and

after. Drink 16 oz per pound lost.

What to Drink• Water

– Short duration activities (<1 hour)

– If eating regularly– If it’s all you got!

• Sports Drinks– Long duration

activities (>2 hours)– Not eating regularly– Need extra

carbohydrates– Not heat

acclimatized

High IntensityShort Duration (<1 Hour)

Type of Fluid

Frequency Volume

Before 5-8% CHO 1-2 hours before

8-16 oz

During Water As needed 16-32 oz

After 5-8% CHO 0-2 hours after

16-32 oz*

*match to weight loss

Moderate-High Intensity1-3 Hours

Type of Fluid

Frequency Volume

Before Water 0-2 hours before

8-16 oz

During 5-8% CHO Every 20-30 min

12-24 oz

After 5-8% CHO 0-2 hours after

8-16 oz/30 min*

*match to weight loss

Too Much Hydration

• Military Medicine: several deaths

• Ironman: 30% of finishers

• Hyponatremia

• Prevention?

QUESTION

• What are the six essential nutrients?

• What is the recommended % of fat, carbohydrates and protein?

CALORIES AND DIETARY RECOMMENDATIONS

CALORIE

• A measure used to express the heat/energy value of food and physical activity.

• Calorie computation example:% Fat in 8 oz. glass of whole milk

Grams cal/gmCarb 12 X 4 = 48

Fat 8.6 X 9 = 77.4Protein 8.5 X 4 = 34

159.4Fat/total cal 77.4/159.4 = 48%

HEALTHY LIFE STYLE

• For a healthy lifestyle:

– Carbohydrates should make-up 45-65% of diet.

– Protein ~15% of diet.

– Fat 30% or less.

NUTRITION

Basal Metabolic Rate (BMR)

• Is the amount of energy required to maintain life

• Accounts for the majority (70%) of the total daily calories expended

Calculating BMR (cal/day)

• Age (years): Equation:

• Men: 18-30 6.95 x bodyweight(lbs) + 679

• 30-60 5.27 x bodyweight(lbs) + 879

• Women:18-30 6.68 x bodyweight(lbs)+496

• 30-60 3.95 x bodyweight(lbs)+829

• Your BMR is____________cal/day.

ACTIVITY FACTOR

• 1.2 - very light physical activity (sitting, standing, driving, lab work)

• 1.4 - light physical activity (housecleaning, walking 3 mph)

• 1.6 - moderate physical activity (tennis, weeding, walking 4 mph)

• 1.9 - strenuous (full court basketball, heavy digging, long distance running)

• 2.3 - exceptionally heavy physical activity (competitive triathlete, Navy SEAL)

Daily Estimated Energy Requirements (EER)

• Calculate your total daily estimated energy requirements (EER) by multiplying the cals needed for your BMR by your physical activity factor.

• Energy Needs = BMR x Activity Factor

• EER =_________cal/day

EXAMPLES

• 36 year old male.• Light physical activity

• 2580 Calories

• 36 year old male.• Very heavy physical

activity

• 5000 Calories

RECOMMENDED DIETARY

ALLOWANCES• RDA’s:

– Set by the food and nutrition board, National Academy of Sciences and National Research Council.

– Designed for practically all people in the U.S. (98% of pop.)

WEIGHT LOSS

OBESITY

• 61% of Americans are overweight or obese. • Defined as 20% above desirable weight. • All populations are increasing in obesity with minority

women as high as 50%. • Can lead to diabetes, hypertension, hyperlipemia,

cancer, cardiovascular disease, sleep apnea and gout. • Very complex condition. • Never the result of just one factor, but has many

etiologies, which may include: genetic component, environmental/social lifestyle, food selection, inactivity, and behavioral conditions.

DIETS

• You can’t win a battle with food.

• 95% failure rate!

• Often extreme or unbalanced.

• Too hard to comply with.

THE KEY TO WEIGHT LOSS

• 3500 calories per pound of fat.

• 500 per day for 1 pound per week.

• Reduce calories by 500/day and burn 500/day = 2 lbs per week.

Calories

Burned

Calories

Eaten

Calories

Burned Calories

Eaten

WHAT DOESN’T WORK?

• Starvation or severe calorie restriction.

• This will result in:– Lean muscle loss.– Loss of fluid.– Lowering of metabolism.

• Once eating returns, member returns to pre-diet body weight.

WEIGHT LOSS

• What works?

Moderate calorie restriction, regular aerobic exercise, combined with strength training,

low fat/high fiber

diet, and behavioral changes.

SPOT REDUCTION

• No Such Thing!!!

                                        

EASY STEPS TO GET ON THE RIGHT

TRACK• 1. Clean up your diet a bit.

• 2. Eat at least 3 but preferably 6 times per day.

• 3. Balance your carbohydrates, protein and fat.

• 4. Exercise, at least a little, every day.

QUESTION

• What are the best methods for weight loss?

NUTRITIONAL SUPPLEMENTS

NUTRITIONAL SUPPLEMENTS

• 1994 DSHEA– Supplements are

not tested for purity!

– Supplements are not tested for safety!

• Several problems reported with legal supplements

1. Don’t believe anything you read about nutrition or supplements written by somebody trying to sell you something.

1ST COMMANDMENT OFNUTRITION

RELIABLE SOURCES OF NUTRITION INFORMATION

• RD - Registered Dietitian

• RDT - Registered Diet Technician

• ADA - American Diatetic Association

• AHA - American Heart Association

• AMA - American Medical Association