Human Nutrition Flashcards
Carbohydrates
quick release of energy, easily digestible and transportable
Carbohydrates ( sugar/starches )
quick energy, short term storage, easily digestible and transportable, used as body’s primary energy source
Lipids ( fats )
2x energy per gram than carbs, long term storage, harder to digest and transport
Proteins
long chains of amino acids and carbon atoms
What can proteins be used for?
cellular respiration
What can proteins be used for?
cellular respiration
What can proteins be used for?
cellular respiration
Why can excess amino acids not be stored in the body?
Proteins are harder to metabolize and they produce nitrogenous wastes that must be removed from the body
1 food calorie=
1000 calories
How is the energy content of a food calculated?
burning a known mass of a food sample, the energy content of the food can be calculated by measuring the heat energy released from the burning food using a calorimeter
What is the equation to calculate energy content of food?
Mass of water (g) x 4.2 (J/g℃) x Temp increase (℃)
What must be held constant in calorimetry?
-mass of food sample
-mass/ volume of water (1g = 1ml)
-starting temperature of water
-distance between calorimeter and burning food sample
Nutrient
a chemical substance found in food that is used in the body
What are the six different types of nutrients?
Carbohydrates, lipids, proteins, vitamins, minerals, and water
What is an essential nutrient?
A nutrient that cannot be replaced or synthesized by the body, so it must be ingested in the diet
What is a non-essential nutrient?
A nutrient that can be synthesized by the body or have a replacement nutrient which serves same dietary purpose
Examples of essential nutrients
Water
Minerals
Some vitamins
Some unsaturated fatty acids
Some amino acids
Examples of non-essential nutrients
Carbohydrates/sugars/ starches (energy could come from proteins/fats)
Other minerals and some vitamins
Saturated fatty acids
Some amino acids
What are dietary minerals?
Dietary minerals are inorganic elements in ionic form
How is muscle cramping caused?
electrolyte imbalance, Na and Ca
What are vitamins?
Vitamins are organic carbon-based compounds
Water soluble
excess lost in urine so need to be consistently
consumed = B, C
Fat Soluble
Fat-soluble (can be stored within the body/ liver = A, D, E, K)
What is the function of Vitamin C
Collagen production (healing & skin growth), immune system, blood vessel elasticity
Sources of vitamin C
Fruit; citrus
What is the function of vitamin A?
Eye function, vision, hair, skin
Sources of Vitamin A
Dairy, meat, and fish
What is the function of Vitamin B?
Nervous system control, digestion, coenzymes
Sources of vitamin B
Dairy, meat, spinach, broccoli, bananas
What is the function of vitamin D?
Calcium absorption – bones & teeth
Sources of vitamin D
Fish oils, egg yolk, enriched dairy products
Vitamin C
Absorb Acid
What does the synthesis of Vitamin C require?
The synthesis of Vitamin C from glucose requires four enzymes
What is the result of failure to ingest Vitamin C?
Failure to ingest adequate amounts of Vitamin C results in scurvy (and weakened immune system function)
What is the effect of a lack of Vitamin D?
Lack of vitamin D or calcium can affect bone mineralization and cause rickets or osteomalacia
What does Vitamin D aid?
Aids in the formation and reparation of bones aids in the absorption of calcium and phosphorus
Rickets
Develops in children when the bones near the growth plates do not mineralize properly
Leads to irregular, thick & wide bone growth
(decreased height/ bowed legs )
Osteomalacia
Bone plates in adults are fully formed so
you cannot develop rickets but you may develop a similar condition called osteomalacia = “soft bones”(painful/ weak bones, difficulty walking, increased fractures)
Osteomalacia
Bone plates in adults are fully formed so
you cannot develop rickets but you may develop a similar condition called osteomalacia = “soft bones”(painful/ weak bones, difficulty walking, increased fractures)
What are the two essential fatty acids?
Omega 3 and Omega 6
Why are omega 3 and omega 6 essential?
omega-3 & omega-6) are ESSENTIAL (required) in the human diet since we lack the enzymes to make these fatty acids from other fatty acids or precursors (triglycerides/ phospholipids
Where can omega 3 and omega 6 found?
fish, walnuts, and leafy vegetables
How is a fatty acid determined?
A fatty acid type is determined by the number of carbon atoms and the number of locations and double bonds
Describe fats and cholesterol
Fats and cholesterol are non-
polar/ hydrophobic (difficult to
transport in the blood)so they are
“packaged” with proteins to
form transport structures called
lipoproteins.
What are the two types of lipoproteins?
LDL and HDL
What is the function of LDL?
carry cholesterol FROM the liver TO the body
What is the function of HDL?
carry cholesterol FROM the body TO the liver
What do saturated fats do?
increase LDL levels, increase blood cholesterol
What do trans fats do?
Increase LDL levels decreased HDL levels, and significantly increase blood cholesterol
What do cis-polyunsaturated fats do?
Increase in HDL levels, decrease in blood cholesterol levels
Atherosclerosis
build-up of plaque deposits in arteries
Atherosclerosis
build-up of plaque deposits in arteries
Conditionally non-essential
some aa’s are only essential during infancy or pregnancy, or for people suffering from a particular disease
Lack of one or more essential amino acids
certain proteins cannot be synthesized (protein deficiency
Phenylketonuria
genetically inherited disease
How is Phenylketonuria caused?
caused by a person’s chemical inability to metabolize the aa phenylalanine (into tyrosine)
What is the result of excess phenylalanine?
Excess phenylalanine may result in mental deficiency, behavioral problems, seizures & other developmental problems
Malnutrition
Malnutrition is a health condition that is caused by a deficiency, imbalance, or excess nutrients in the diet
What is the recommended daily calorie intake?
2000 calories/ 8700kJ (BUT varies based on age, gender, activity, medical conditions, etc.)
What controls a persons desire to eat?
the hypothalamus
How is body mass index calculated?
Mass in kg/ (height in m)^2
What are factors that influence obesity?
Increase in sugar rich, high-energy food consumption, decrease in physical exercise
