Lecture 23 Minerals

1
Lecture 23 Minerals
2
Minerals What are they?

• Inorganic elements
• 2 classifications
• i) Macro minerals (5g in human body)
• Calcium Sodium
• Phosphorous Chlorine
• Magnesium Potassium
• Sulphur

3
Minerals

• ii) Micro minerals (
• Iron Selenium
• Zinc Manganese
• Copper Molybdenum
• Iodine Cobalt
• Chromium Vanadium
• Fluorine Tin
• Silicon Nickel
• have dietary roles

4
Minerals important to health

• 1. Those in the food supply
• eg. iron, calcium, sodium, chlorine
• 2. Iron-enriched foods
• eg. breakfast cereals
• 3. Calcium-enriched foods
• eg. calcium-fortified Soy milks

5
Minerals important to health

• 4. Fluoridated water supply
• 5. Low-sodium processed foods
• eg. soups, baked beans, crackers
• NB. Lite salt Celery salt still contain
  sodium chloride

6
Minerals What do they do?

• Calcium
• 99 in bones and teeth
• Function bone/teeth structure
• enzyme activity
• muscle contraction

7
Calcium

• Deficiency Rickets
• Osteoporosis
• Osteopaenia
• Cardiac arrest
• Toxicity kidney stones?

8
Calcium

• At risk
• post-menopausal women
• female athletes
• pregnant women
• children

• strict vegetarians (vegans)
• fad dieters
• others who avoid dairy foods
• (eg. Lactose intolerant)

9
Food Sources of calcium

• Dairy
• cows milk 310mg calcium/ 265g cup
• yoghurt 255mg calcium/ 200g tub
• Fruche 100mg calcium/ 100g tub
• cheese (low fat) 155mg calcium/ 20g slice
• ice cream 36mg calcium/20g scoop
• fortified Soy milk 295mg calcium/255g cup
• non-fortified SM 34mg Calcium/255g cup

10
Food Sources of calcium

• Canned fish (with bones)
• Salmon 220mg calcium/ ½ cup (120g)
• Sardines 215mg calcium/ 5 sardines
• Mackerel 34mg calcium/ 148g cup
• Sesame seeds
• Hommos (tahini paste) 69mg/ 20g Tbsp

11
Calcium - food sources

• Leafy green vegetables
• cabbage 90mg calcium/ 180g cup
  (cooked)
• nuts
• almonds brazil 130mg/ 60g cup
• peanuts walnuts 40mg/ 60g cup
• cashews 20mg/ 60g cup

12
Calcium - RDI

• Adults ? 800mg/day
• ? 3 glasses milk/day
• 1 glass milk ? 2 slices cheese
• ? 1 tub yoghurt (200g)
• ? 2 tubs Fruche (2x100g)
• ? 4 Tbsp Hommos

13
Calcium - RDI

• Pregnant women 900-1300mg/day
• Lactating women 900-1300mg/day
• Post-menopausal women 1500mg/day

14
Minerals what do they do?

• Iron
• Function
• oxygen transport (haem iron)
• carbon dioxide transport
• cellular electron transfer (energy production)

15
Iron

• Storage
• as FERRITIN in intestinal mucosal cells
• Deficiency
• microcytic anaemia (small pale RBC)
• Toxicity
• haemochromatosis (liver damage from excess iron
  stores?)

16
(No Transcript)
17
Iron

• At risk
• female athletes
• fad dieters
• vegans

18
Iron

• Absorption
• best haem iron (animal sources of iron)
• up to 20 absorbed
• poor non-haem iron (vegetative sources)
• only 2-8 absorbed

19
Iron

• Improved absorption
• non-haem iron
• orange juice
• Ribena (blackcurrant juice)
• Haem-rich foods
• transforms ferrous to ferric iron
• chemical reduction reaction

20
Iron

• Impaired absorption
• Oxalates (spinach)
• Phytates (cereals)
• Polyphenols (eg. tannin in tea)

21
Iron - RDI

• Adults
• males ? 7 mg/day
• females ? 12 mg/day
• pregnant women ? 15 mg/day
• lactating women ? 15 mg/day
• athletes ? 12-15mg/day ??

22
For your amusement

• A video/cartoon Store Wars from the Organic
  Trade Association
• http//www.storewars.org/flash/index.html

23
Recommended Reading

• Walqvist, M. (Ed.) 2002
• Food Nutrition (2nd ed.)
• Chapter 17 Minerals
• Whitney Rolfes (2005)
• Understanding Nutrition (10th Ed.)
• Chapter 12. Water the Major minerals
• Chapter 13. The Trace minerals