nutrition- chapter 8 Flashcards
1
Q
classes of minerals
A
major minerals:
- intake of more than 100mg/day
- calcium, phosphorus, sodium, potassium, magnesium, chloride, and sulfur
trace minerals:
- intake of less than 100mg/day
- 18 elements
2
Q
functions of minerals
A
- building tissue
- influencing metabolic processes
3
Q
mineral metabolism
A
- do not require much digestion
- absorbed in ionic forms; rate determined by food form, body need, tissue health
- enter through portal circulation, bound to proteins
- controlled by hormones
- basic forms are free ions and covalently bound
4
Q
calcium
A
- functions: bone and tooth formation, blood clotting, muscle and nerve action, metabolic reactions
- requirements: a varied diet provides enough calcium to meet DRI
- deficiency: insufficiency during growth years increases the risk for bone deformities
- toxicity: unlikely from food sources; excessive supplementation is associated with calcification of soft tissue and decreased bioavailability of several essential nutrients
food sources: milk and milk products
5
Q
phosphorus
A
- functions: bone and tooth formation, energy metabolism, acid-base balance
- requirements: a varied diet provides enough to meet DRI
- deficiency: occurs with excessive intake of antacids containing aluminum hydroxide
- toxicity: unlikely from food sources; if phosphorus intake is higher than calcium intake for a long period, bone resorption may occur
- food sources: high-protein foods, plant seeds, dairy, legumes
6
Q
sodium
A
- functions: water balance, muscle action, nutrient absorption
- requirements: needs vary depending on growth stage, sweat loss, and medical conditions
- deficiency: rare, except with heavy sweating
- toxicity: increased blood pressure in salt sensitive individuals, hypernatremia
- food sources: table salt, animal products, carrots, beets, leafy greens, celery
7
Q
potassium
A
- functions: water balance, metabolic reactions, muscle action, insulin release, and blood pressure
- requirements: average intake (2.6mg) adequate for women, but not for men. must not get too much or too little. important for heart function
- deficiency: rare from dietary intake, more likely from vomiting, diarrhea, malnutrition, or surgery
- toxicity: excessive oral or IV intake causes hyperkalemia
-food sources: oranges, bananas, potatoes, leafy green vegetables, fish, whole grains, legumes, seeds, milk products
8
Q
chloride
A
- functions: digestion and respiration
- requirements: need for chloride declines after 50
- deficiency: primary reason is vomiting
- toxicity: only known dietary cause is severe dehydration
- food sources: table salt
9
Q
magnesium
A
- functions: metabolism, protein synthesis, muscle action, basal energy expenditure
- requirements: the average American only consumes 84% of the recommended intake
- deficiency: rare with balanced diet; caused by renal disorders, starvation, persistent vomiting or diarrhea, genetic mutations, over-suctioning
- toxicity: unlikely from food sources; from supplements or non-food sources, may cause nausea, vomiting, diarrhea
- food sources: nuts, soybeans, legumes, whole grains, oats, and cocoa, hard water
10
Q
sulfur
A
- functions: hair, skin, nails; general metabolic functions, vitamin structure, collagen structure
- requirements: supplied by protein foods
- deficiency: occurs with protein malnutrition and deficient intake of sulfur-containing amino acids
- toxicity: unlikely from dietary intake
- food sources: meat, eggs, milk, cheese, legumes, and nuts
11
Q
iron
A
- functions: hemoglobin synthesis, metabolism
- requirements: needs vary depending on growth and development
- deficiency: due to iron-deficiency, micronutrient deficiencies other than iron, chronic infections, and genetic mutations
- toxicity: a single large dose is potentially lethal
- food sources: meat, fortified cereals, and some vegetables; absorption enhanced by vitamin C
12
Q
iodine
A
- functions: component of thyroxine
- requirements: 14 and older: RDA is 150mcg/day
- deficiency: goiter, cretinism, impaired mental and physical development, hypothyroidism
- toxicity: excess iodine supplements may lead to thyrotoxicosis or iodine-induced hyperthyroidism; UL in healthy adults is 1100 mcg/day
- food sources: seafood, iodized table salt
13
Q
zinc
A
- functions: enzyme function; DNA, RNA, and protein synthesis, energy metabolism, food intake regulation, immune function, and others
- requirements: adequate daily intake is required
- deficiency: contributes to myriad health issues
- toxicity: uncommon from food sources, self-limiting from supplements due to side effects; UL is 40mg/day
- food sources: meat, seafood, legumes, whole grains
14
Q
selenium
A
- functions: essential part of body tissues, glutathione peroxidase, selenoproteins; protects against free radical damage
- deficiency: negatively alters immune function
- toxicity: hair loss, joint pain, nail discoloration, and gastrointestinal upset; 14 years and older: UL is 400 mcg/day
- food sources: pork, turkey, lamb, chicken, organ meats, fish, whole grains, seeds, brazil nuts
15
Q
fluoride
A
- accumulates in calcified body tissues; over 9 years of age: UL is10mg/day
- found in water supply, crab, shrimp, raisins, grape juice, hot breakfast cereals, tea
