KNES 337 - Unit 24 Water and Unit 25 Dietary Supplements

how much of the adult body is water?

55-60%

water balance

• Intake - liquids (550-1500 ml), foods (700-1000 ml), water created by metabolism (200-300 ml)

• Output - kidneys (500-1400 ml), skin (450-900 ml), lungs (350 ml), feces (150 ml)

daily fluid recommendations

varies depending on diet, activity, temperature, and humidity

• Adult who expends 2000 kcal/day needs about 7-11 cups/day of fluid

water in foods

• Beverages are 85-100% water

• Fruits and vegetables 75-90%

• Meats are 50-70%

• Water in foods contributes to our fluid intake

  • 31% of intake from plain water

  • 44% from other beverages 

  • 25% from foods

increase water needs

1. Diseases that disturb water balance (such as diabetes)

2. Exercise

3. Forced air environments, such as airplanes or sealed buildings 

4. Hot weather 

5. Increased dietary fiber, protein, salt, or sugar

6. Drugs and medications (diuretics - alcohol, caffeine)

7. Pregnancy or breastfeeding

8. Prolonged diarrhea, vomiting, or fever

9. Surgery, blood loss or burns

10. Very young or old age (smaller body mass makes minor changes in hydration more serious, elderly sense of thirst reduced)

fluid losses

• Heat = sweat losses of 1-2 L/hr exercising in heat

• Cold = cold induced diuresis (cold-weather-induced need to urinate) increases fluid loss

• Dehydration reduces ability to dissipate heat causing increased body temperature

• Dehydration >2% body mass leads to significant reductions in endurance exercise performance

dehydration

reduces ability to dissipate heat causing increased body temperature

• Dehydration >2% body mass leads to significant reductions in endurance exercise performance

-5 degrees C

0.6-1.4 litres lost per hour

10 degrees C

1.2-1.5 litres lost per hour

20 degrees C

1.6-2.5 litres lost per hour

30 degrees C

2.0-2.8 litres lost per hour

water toxicity

high intake of water, rare, leads to

• Hyponatremia (low blood sodium)

• Swelling of body tissues

• Excessive water accumulation in the brain and lungs

• Confusion, severe headache, nausea, vomiting, seizure, coma, and death

water intoxication occurs in

• Endurance athletes who consume too much water

• Infants given too much water or over-diluted formula

• Patients with psychiatric disorders taking medications that produce cravings for water

fluid replacement

• 500 ml -- 2 hours before exercise

• 150-300 ml -- every 20 min during exercise 

• Exercise < 60 min -- water is best replacement

• Exercise > 60 min -- dilute glucose and electrolyte solutions

• volume, temperature, composition matter

volume for fluid replacement

small volume, regular interval to prevent bloating

temperature for fluid replacement

cool (5-10 degrees C) to maximize ingestion

composition for fluid replacement

• >10% CHO may inhibit gastric emptying resulting in diarrhea, nausea, cramping

• 6-10% glucose or sucrose absorbed rapidly and provide energy for prolonged exercise 

mineral water

taken from underground reservoirs between layers of rock, contains dissolved minerals from the rock

spring water

taken from springs that form pools or streams

sparkling water

carbonated water (true seltzers are naturally carbonated but sparkling is usually commercial addition of pressurized CO₂)

• Estimated that ~45% of bottled water is (purified) bottled tap water

supplements

called natural health products by Health Canada

include vitamins and minerals, probiotics and prebiotics, herbal remedies (e.g. garlic), homeopathic medicines, traditional medicines such as traditional Chinese medicines, other products like amino acids and essential fatty acids 

• Can buy without prescriptions

• Shouldn’t rely on them to get nutritions, food is always the preferred source of vitamins and minerals 

risks of supplements

• May list ingredients on the label differently to how they would appear on the Prohibited List

• Counterfeit (fake) supplements, especially when purchased online

• May be contaminated (with banned or other substances - lead, mercury, heavy metals)

• May contain more or less than listen on label, or may not contain ingredient at all

  • Common with preworkouts 

• May not work, or even have the opposite effect of what is claimed

• May be adulterated 

regulation of supplements

• Not a lot in Canada

• No vigorous testing by Health Canada or Food and Drug Administration (FDA)

• Legislation now requires natural health products to have a natural product number (NPN)

  • Safe, effective and high quality - documents submitted by company

  • Can identify them in a database

Responsibility lies with the consumer to be informed!!!!

united states pharmacopeia (USP)

a voluntary program - third party testing

• Dietary Supplement Verification Program - open to manufacturers of dietary supplement finished products from around the world

• Option - can also label the product as a house standard (e.g. manufacturer’s name standard)

USP verified

• Contains the ingredients listed on the label, in the declared potency and amounts

• Does not contain harmful levels of specified contaminants (e.g. lead, mercury, microbes, pesticides, or other contaminants)

• Will break down and release into the body within a specified amount of time

• Has been made according to FDA current Good Manufacturing Practices using sanitary and well-controlled procedures

  • Assurance of safe, sanitary, well-controlled, and well-documented manufacturing and monitoring processes

  • Consistent quality

considerations for athletes

higher stakes, violations, can end a career

anti-doping violations

• occurs when a prohibited substance is found in an athlete’s body

  • Can end a career

  • Whether or not the athlete intentionally or unintentionally used a prohibited substance or was negligent or otherwise at fault

    • It doesn’t matter…if it’s there it’s a violation

  • Ignorance is never an excuse!

    • take responsibility and educate yourself

therapeutic use exemption

• doctor has said you need it for your health, that’s ok!

canadian centre for ethics

education on supplements

third-party testing - someone not a part of the company tests it independently

high vs. low risk supplements

supplements for muscle-building, weight-loss, sexual enhancement, and energy, diuretics

should you take vitamins or minerals?

consider health status, special circumstances, the nature of the nutrient (accessibility through diet)

health status for vitamins and minerals

• Some individuals might not be able to consume, digest, absorb, or make use of some vitamins or minerals

  • Due to pregnancy, disease, pancreatitis, short bowel syndrome, or liver or renal diseases 

• Normally, people might not receive enough of it through diet, e.g. limited or inaccessible dietary sources (vitamin D)

special circumstances

Some individuals might need more vitamins and minerals during particular times, and are not able to meet requirements through foods consumption 

• E.g. pregnancy, excess bleeding

are supplements better than food?

• Vitamin E - natural more rapidly absorbed and maintained in tissue, about 2x as potent

• Vitamin C - natural and synthetic have equal potency, pills, foods, or rose-hip extracts = same 

how to take vitamins and minerals

multivitamins → take with meal

iron → with meal or glass of juice, avoid taking with tea or coffee (for absorption) - if anemic, not at same time as Ca

Calcium → calcium carbonate with a meal, divide large doses, Ca + Vitamin D is a good idea (in winter, if no multivitamin is taken)

taking multivitamins

take with a meal

taking iron

with meal or glass of juice for Vitamin C, avoid taking with tea or coffee (for absorption) - if anemic, not at same time as Ca

taking calcium

calcium carbonate with a meal, divide large doses, Ca + Vitamin D is a good idea (in winter, if no multivitamin is taken)

whey protein

improving sport performance, immunomodulation, antibacterial, antiviral, and antifungal activity

Generally safe, but is a supplement - found many protein powders contained heavy metals, pesticides or other contaminants with links to cancer and other health conditions 

creatine

increases bioavailability of phosphocreatine (PCr) in muscle cells - faster resynthesis of ATP (fuel for cellular processes), brief high intensity exercise 

• Body can synthesize PCr from amino acids

  • Vegetarians may have lower PCr stores, and may benefit more from supplementation

recommended creatine

0.3g/kg/day of creatine monohydrate for 5-7 days followed by 3-5g/day thereafter to maintain elevated stores

literature on creatine

creatine supplementation is effective in lower limb strength performance for exercise with a duration of less than 3 min - independent of population characteristic, training protocols, and supplementary doses and duration 

• Can also improve health, reduce risk of bone fractures 

potential safety concerns for creatine

• Kidney and liver function

• Muscle injury

• Suppress natural creatine synthesis

• Promote dehydration and muscle cramping

• No evidence from well-controlled studies (up to 5 yrs) have supported any of these concerns

essential fatty acids

omega-3 supplements

omega 3 supplements

help with heart health, autoimmune diseases, depression, brain development in infancy

high doses of omega 3 side effects

• High blood glucose

• Bleeding

• Low blood pressure

• Diarrhea

• Acid reflux 

herbal supplements

Taken because they’re considered natural and therefore healthier and safer or for a specific condition or general health

are herbs effective

• Many health benefits

• Lacking well-controlled research studies

• Short-term and long-term risks and benefits 

• Testing

  • Consumer Lab found 25% of 30 brands of ginkgo biloba (e.g. for memory loss) didn’t have expected levels of active ingredient

  • 25% of 260 herbal products had high heavy metal contamination 

are herbs safe

side effects may include liver damage, heartbeat speeding up, kidney damage, etc.

probiotics

live microorganisms which when administered in adequate amounts confer a health benefit on the host

prebiotics

substrates selectively utilized by host organisms that confer a health benefit

risks of pre and probiotics

• Both are generally safe but might cause problems in some

• Probiotics

  • Mild digestive symptoms (gas, bloating, usually temporary)

  • Small risk of infection and sepsis in susceptible people (immunosuppressant drugs, premature infants, critical illness)

  • Check for allergens in ingredient list (e.g. fillers)

• Prebiotics

  • Mild digestive symptoms (gas, bloating, usually temporary)

  • Starting with low dose and increasing slowly helps

  • May worsen symptoms of irritable bowel syndrome (IBS) in some individuals

take home message on supplements

• no experts recommend routine use of supplements, some agree there is a benefit whe following recommended daily allowance

• foods is more than the sum of its nutrients

• there can be detrimental effects on health

• vary in quality

• focusing on supplements can take attention away from improving lifestyle - false sense of security