Social Welfare In the US there is a food stamp program for those who are unemployed etc. This raises political issues based on taxes. Geopolitics Many countries that cannot grow food and are dependant on importing food, which has led to armed con? ict. Groups vie to control the food because if you can control the food then you have bargaining and political power. LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 Most Canadians are extremely privileged and are not aware of food shortages around the world because food is so abundant at fairly reasonable prices.
Bargaining and political power often leads to armed con? ict. 2 FOOD, SCIENCE AND WORLD PEACE Norman Borlaug (Mar 25, 1914 – Sept 12, 2009) 1970 Nobel Peace Prize • Invented a new strain of wheat (dwarf) which was disease resistant and generated high yields to combat world hunger. • Exported the new strain to Central America, Middle East, India, Pakistan, Africa He developed a new strain of wheat which was disease and wind damage resistant. The very long tall wheat, can topple over and breaks before the grains can be yielded. The dwarf wheat is less prone to buckling and breakage and therefore increases the yield.
Dealt with a lot of hunger problems and food shortages in countries that have trouble growing wheat. WHY ISNUTRITION IMPORTANT? Nutrition can prevent disease. a. Diseases caused by nutrient deficiency: scurvy, goiter, rickets 1:1 relationship b. Diseases influenced by nutrition: chronic diseases such as heart disease c. Diseases in which nutrition plays a role: osteoarthritis, osteoporosis LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 What do we know about obesity? It has gone up, it is staying up. NUTRITION AND OBESITY IN CANADA 3 In Canada, US, etc.
– there is a big increase in the % of the population that is characterized as obese and it is consistent across age spectrum. it is known as an “epidemic”. Different from most diseases, as most are caused by person to person transfer of microorganism. You can’t give someone obesity. The increase in numbers are over a very short time. Lots of health related and economic problems caused by obesity. It is important because of its strain on the health care system. Why do we eat the way we do?…… we’re influenced 1) Physiological hunger Driven by hormones and the nervous system.
We feel sensations of hunger and we seek to alleviate perceptions by eating. It is instinctive. 2) Sensory stimulation ? Food flavour: ? Texture: taste and smell We associate pleasurable experiences with eating food. “feel” of food – crisp, chewy, smooth Studies suggest humans prefer the texture of food rather than the taste. Ex. Skim Milk vs. 2% – the fat content is very different, 2% is thick, where as skim is like water. Titanium dioxide used to be added to skim milk to give it texture, but is not healthy to ingest. 3) Personal preferences Food we select is based upon experiences and what we are raised with and exposed to.
Over time as our perceptions become shaped we form our own experiences we develop personal preferences. 4) Habits: 3 meals/day There is no scienti? c evidence for 3 meals a day. It is just a habit we have developed here in Canada based on our life style but there is no evidence to suggest that it is how humans are supposed to eat. 5) Ethnic heritage or tradition Dictated by food availability in certain geographic locations. ? One of the strongest influences on our eating habits/patterns a) Cultural beliefs and traditions b) Religion – established rules Ex. Rhinoceros Beetle – source of vitamin A and protein. It
is a delicacy and tradition in some countries however we would not eat it in Canada. LS 2N03 – Human Nutrition for Life Sciences Certain religions have rules: what and when we should be eating D. M. Pincivero, 2013 4 6. Social interactions Many times you interact with friends and family it is usually around a meal. You dictate your relationships with people based on food. Ex. Dates – dinner = big commitment, lunch = less commitment 7. Availability, convenience, and economy Something that is good for us is usually $$$, unhealthy food is usually cheap and more available. 8. Positive and negative associations: commercial advertising
Eat something, makes you sick = negative memory, you wont have that food again. Eat something and something positive happens = positive memory. You formulate memories and depending on what we are doing and associate it with foods. Commercial advertising is also very positive, Ex. Dr. Oz. 9. Emotions: comfort…. instinctive for newborns • • • Comfort food: Food provides comfort during periods of psychological distress. Can be instinctive, ie. breast feeding in new borns. Food cravings Beta-endorphins (popular theory for feelings of pleasure) Give us a “high” after eating certain foods.
Pica: craving for non-food items (dirt, clay)…pregnancy 10. Values Vegetarianism: some people choose it out of moral values for not killing animals. When you kill an animal for food, you fuel that sector of the economy. You contribute to more killing and global warming etc. 11. Body weight and image In the short-term it is a strong motivating factor in the long term it is not very effective. DIETS!! Diets address self image but most do not work. 12. Nutrition and health benefits Tied to education. People become informed on bene? ts but it might not be enough to create a change in eating habits.
Tied to traumatic health events. People get “scared straight”, person is engaging in destructive behaviour and some key event (ie. heart attack, stroke) happens that will have a direct threat to their way of life which causes the person to change attitudes and behaviours to improve overall health. LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 5 SPORTS SUPPLEMENTS Global market value, 2009: US$4. 6 billion (does not include sports drinks, United States largest consumer, two-thirds in world) 1) Sports drinks • Provides carbohydrates and fluid….. enhance exercise performance and recovery.
• In Canada 2009, valued at $423 million When we exercise we lose water and it stays lost unless we replace it. Sport drinks replace water and the carbohydrates • Gatorade and Powerade “sugar water” that we burn. Ingesting carbs during exercise has proved to be bene? cial. 2) Sports food • Typically found in a bar format • Nutrient dense and leverages the functional food proposition; that is, it provides health benefits that go beyond their nutritional value Functional food: selection of food selected for maximizing health bene? ts • Whey and soy are dominant ingredients
• In Canada, 2009, sales at $85. 4 million 3) Sports supplements Objectives • Build muscle tissue, increase energy stores/utilization, decrease body fat. Some raise metabolic rates – ephedrine Forms: • Tablets, powders, ready-to-drink Typical ingredients: • Soy protein, whey protein, creatine, L-carnitine and amino acids (does not include sports drinks) Market share: Canada, 2009: • $114 million Whey protein is much more popular than soy protein: whey is superior to soy because of its quality and digestibility. Creatine: Contributes to energy turnover of muscle cells during exercise
Carnitine: Dipeptide that enables muscle cells to break not fatty acids for energy. Fatty acids = more energy dense than carbs. Amino Acids: Protein essential macro nutrients. LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 Protein is designed to be taken after exercise, that is when our cells are most sensitive. 6 Nutrient • Any substance in food that the body can use to obtain energy, synthesize tissues, or regulate physiological/physical functions. Anything that are cells are doing require macro and micro nutrients, and the food that we take in provides those nutrients.
Essential nutrient An essential nutrient is not a important nutrient. • A substance that must be ingested because the body cannot make it or adequate amounts of it. Cells have the capacity to make some nutrients (ie. Vitamin D) unfortunately we cannot make them in the winter. Ex. Vitamins, amino acids, certain fatty acids (Omega 3), carbohydrates Macronutrient • A nutrient that is needed in relatively large amounts in the diet (carbohydrates, fats and proteins) Nutrients that provide energy to our body Micronutrient • A nutrient that is needed in relatively small amounts in the diet (vitamins and minerals).
Do not carry energy but provide the body with key small molecules to break down macronutrients (ie. glycolysis) Organic • In chemistry, any compound that contains carbon, except carbon oxides. Inorganic • Any substance that does not contain carbon, except certain simple carbon compounds (carbon dioxide). “Organic” food • Food growth without use of fertilizers, hormones, antibiotics, etc. LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 7 “Organic” food • Must meet standards of the Canadian Organic Products Regulations. • Crop production • Livestock production • Processing
• Cleaners, disinfectants, sanitizers • Health care products Organic = conditions in which the plant was cultivated. The soil Example: Soil and crop nutrition must meet certain regulations as well. • Over 100 different substances regulated “Bone meal: Permitted only if guaranteed free of specified risk materials including the skull, brain, trigeminal ganglia (nerves attached to the brain), eyes, tonsils, spinal cord and dorsal root ganglia (nerves attached to the spinal cord) of cattle aged 30 months or older; and the distal ileum (portion of the small intestine) of cattle of all ages.
” This suggests non-organic foods probably contains those things. Antioxidant • A nutrient that that combines with or neutralizes free radicals, preventing oxidative damage to the cell. Free radicals are damaging your DNA and causing cells to be pre-cancerous. As we get older we lose the ability to deal with free radicals. Certain foods are better at handling diseases than medicine. Phytochemicals (micronutrients) • “plant chemical”. • Complex chemicals that vary from plant to plant • Example: orange has over 170 distinct phytochemicals
• Function: fight bacteria and viruses, UV lights, free radicals • Health benefits: cancer prevention (free radical and hormone neutralizing), lowering of LDL cholesterol Cardio-protective: reduces blood pressure Oxidative Metabolism: O2 + electrons + protons (ATP) = H2O When something goes wrong: O2 picks up lone eO2- (super oxide anion) – highly reactive – binds with cell membranes, DNA and disrupts membrane structure Enzyme that deal with it is superoxide dismutase. As we our ability to make the enzyme deceases. LS 2N03 – Human Nutrition for Life Sciences Organic vs. Inorganic D. M. Pincivero, 2013
Our cells lose the ability to deal with the free radicals as we age. Cancer: breast, endometrial, and prostate cancer are tied to being affected by what we eat. Trans-fat, sat-fat = bad. , mono-saturated and poly = bene? cial. 8 MACRONUTRIENTS O2 + electrons + protons = ATP for energy to fuel cellular processes (ie. sleeping two muscles must work: cardiac and diaphragm muscles) Our cells break up ATP to harness energy however we need to replace whatever we use. We have to constantly make ATP because we are constantly using it. We combust fats, nutrients and carbs to make ATP. 1) Carbohydrates • “hydrate of carbon”
Purpose: Supplies energy to the cell Storage: Particularly applicable to neurons and RBC (prefer carbs than other macro nutrients). Low carb diet could impair those processes. So our body breaks down protein in our muscles. Liver and skeletal muscles. We have a storage capacity, as we burn through the carbs they stay depleted unless we replace what was lost. Example food sources: Simple or complex CHO Mostly plants, and rarely in animal products (milk) Problems/diseases specific to CHO: – We store carbohydrates as glycogen – In plants: carbs are found as starch, sugars, and dietary ? bre Diabetes mellitus
We ingest ? bre but we can’t break it down. 2) Lipids • Fats, oils, cholesterol, phospholipids Purpose: 1) Building block of phospholipids and glycolipids Structure and stability to cell membranes 2) Protein modification by attaching to fatty acids 3) Fuel Dense form of energy – we can make a lot of ATP to burn fat 4) Derivatives serve as hormones and intracellular messengers Take in and form a number of different molecules Storage: White adipose tissue and brown adipose tissue (fatty tissue found around our internal organs) Adipose tissue made up of fat cells. Example food sources: Meat, dairy etc.
Problems/diseases specific to lipids: Excessive intake leads to many diseases (ex. coronary) Unsaturated = healthy Trans/Saturated Fat = bad LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 9 3) Protein Purpose: Amino acids are the building blocks. AA are assembled in different order and yields different structure and function. Provide structure and energy if necessary. If carbs are not available some amino acids can be converted into glucose (glucogenic). Storage: No central storage location. They are found in all of our tissues. AA are circulating through our body. Example food sources: Meat, ?
sh, dairy, legumes Animal based sources are better that plant based foods – greater amount and quality. We are eating skeletal muscles which are made up of protein. Some plants are high in protein: soy, lentils Problems/diseases: Kwashiorkor: lack of dietary protein, fat deposition into liver, swelling Marasmus: muscle wasting and fat depletion Excess: heart disease (increased fat), cancers (colon, kidney, prostate, breast), osteoporosis (increased Ca+ excretion) Non-protein nitrogenous compounds • Composed of amino acids, but not considered to be protein All are peptides – connecting two or three animo acids together
Examples: • • • • • Glutathione Works with vitamin C as an anti-oxidant Carnitine Molecule mitochondria uses to break up fatty acids for energy Carnosine Dipeptide (two AA) that has anti-oxidant properties Creatine Sports supplement used as an energy supplement, high energy molecule Choline Component of cell membranes and neurotransmitters LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 10 MICRONUTRIENTS Very small molecules that we do not get energy from them, but they enable us to extract energy from macronutrients. Various enzymes that are involved in breaking up macronutrients require micronutrients.
Vitamins • Organic compounds that contain carbon, hydrogen and other atoms (nitrogen, oxygen, phosphorus) Function: • Energy extraction from macronutrients • Calcium balance • Blood clotting 2 groups: 1) Water soluble: B vitamins (8) and vitamin C Subject to ? ltration by the kidney 2) Fat soluble: A, D, E, K Absorbed with dietary lipids More prone to toxicity Minerals • An inorganic nutrient that is needed for growth and regulation of normal physiology • 16 minerals Macrominerals: Major minerals required in the diet in larger amounts than the trace minerals. • Na, K, Cl, Ca, P, Mg, S
Trace minerals: Required in small amounts in the diet. • Fe, Zn, Cu, Mo, Mn, Se, I, Fl WATER LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 11 What is Energy? • An ability to cause changes in, or perform, work, heat and/or mass. • Common definition: ability to perform work. Forms of energy: • • • • • Mechanical Electrical Thermal Chemical Nuclear – moving physical objects moving charges (electrons) increasing temperature (randomness) binding/unbinding of bonds binding/unbinding of nucleons calorie • is the amount of energy needed to raise the temperature of 1 gram of water by 1 degree C.
1,000 calories = 1 kcalorie = 1 Calorie Energy density: amount of energy in a food source relative to its’ mass. Delivers a lot of calories per until mass (g). Nutrient density: amount of nutrients in a food source relative to its’ energy content. Opposite to energy density. Delivers a lot of macro and micro nutrients per kcalorie Where is this food energy?……. chemical bonds (ATP) Which nutrients provide energy?……. macronutrients fats, proteins, carbohydrates How does our body use this food energy?……. metabolism to support life ***ENERGY BALANCE EQUATION***
Energy IN = Energy OUT + E STORAGE Macro = Macro Nutrient Combustion + CHO (liver, skeletal muscles) Lipids (adipose) TYPE OF FOOD Proteins PHYSICAL ACTIVITY LEVEL, DISEASE, DRUGS (effects whether we store or combust macro) LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 12 How much energy do the macronutrients provide? Carbohydrates = 4 kcal/gram Protein = 4 kcal/gram Lipids (fats) = 9 kcal/gram Example: One half avocado • 101 grams, 2 g protein, 9 g carbohydrates, 15 g fat = 161 kcalories Doesn’t add up!!!! = (2 x 4) + (9 x 4) + (15 x 9) = 179 kcalories Why not?….. hint…..
a carb is a carb is a carb? Monounsaturated fat is good for you however they still carry a large amount of calories. Not all carbs are the same: 161 = amount of energy available to our cells 179 = total calories in food item: what is available to us + ? bre The remaining calories are in ? bre which our digestive system cannot break up and absorb LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 13 DIETARY REFERENCE INTAKES ? ? Standards defined for energy nutrients, other dietary components, physical activity Recommendations apply to healthy people ? May be different for specific groups
LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 14 DIETARY REFERENCE INTAKES Estimated Average Requirement (EAR) • The average daily intake level of a nutrient that will meet the needs of half of the people in a particular category. Used to establish the RDA Recommended Dietary Allowances (RDA) • The average daily intake level required to meet the needs of 97 – 98% of people in a particular category. Based on age and requirement Listed on nutritional labels Example: Protein intake for a 19 year old woman = 46 grams/day (10-35%) Number in parenthesis is AMDR Absolute vs. relative (0. 8 grams/kg/day)
This suggests protein should make up 10-35% however the problem is our protein intake should be determined by our body size. Physical activity is also a determinant. Adequate Intake (AI) • Recommended average daily intake level for a nutrient • Based on observations and estimates from experiments • Used when the RDA is not yet established: e. g. , calcium, vitamin D, vitamin K, fluoride Difference between AI and RDA is the amount of evidence to support RDA AI is reported for some, and RDA for other. Either or. Example: Vitamin K for 15 year old male = 75 ng/day Blood clotting factor synthesis, bone protein formation
Food sources: liver, green leafy vegetables, cabbage family Tolerable Upper Intake Level (UL) • Highest average daily intake level that is not likely to have adverse effects on the health of most people • Consumption of a nutrient at levels above the UL is not considered safe • Protects against over-consumption Amount of micronutrient that can be ingested without experiencing toxicity like symptoms Example: Vitamin C – water soluble Taking it near the UL = not bene? cial, because most of it will be excreted Anti-oxidant, prevent iron absorption, amino acid metabolism 55 year old woman = 2000 mg/day
Toxicity: abdominal cramps, diarrhea, haemolytic anemia Children are most prone to vitamin toxicity LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 15 DIETARY REFERENCE INTAKES LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 16 Estimated Energy Requirement (EER) • Average dietary energy intake (kcal) to maintain energy balance • Based on age, gender, weight, height, level of physical activity Acceptable Macronutrient Distribution Ranges (AMDR) • Describes the portion of the energy intake that should come from each macronutrient •
Expressed as ranges (percentage of total energy) with upper and lower boundary. Nutrition Assessment Individual Level • Deficiency or excess over time leads to malnutrition • Symptoms of malnutrition • Diarrhea • Skin rashes • Fatigue • Others • Creating a “total picture” of the individual Body weight is the best predictor of cardiovascular health!! – Historical information • Health status • Diet history – intake over several days; portion sizes; computer analysis – Anthropometric measurements • Height and weight – track to identify trends – Physical examinations
– Laboratory tests LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013 17 NUTRITION INFORMATION Registered Dietitian • http://www. dietitians. ca/ College of Dietitians of Ontario • http://www. cdo. on. ca/en/ Scientific information database: PubMed • http://www. ncbi. nlm. nih. gov/pubmed Credible websites • See Table H1-2 (page 32) • Health Canada (www. hc-sc. gc. ca) • Canadian council of Food and Nutrition (www. ccfn. ca) • University, hospital, health network websites LS 2N03 – Human Nutrition for Life Sciences D. M. Pincivero, 2013