1

2

At least 13 inorganic elements per se are known to be essential for man (the same as the number of vitamins) while others are needed in compounds (P, S, Co). All must be provided for long term nutrition and ensured in infant formulas.

RDA = 700 -1000 mgfor adult, except pregnant and lactatingwomen.

Therapeutic dose range =1000 – 3000 mg

3

1. Bone and tooth structure: Calcium, together with phosphorus, forms hydroxyapatite [Ca10(PO4)6(OH)2] crystals that give strength and rigidity to bone and tooth enamel.The average adult body contains in total approximately 1 kg, 99% in the skeleton in the form of calcium phosphate salts.

2. Important component of blood coagulation (clotting) cascade.

3. Muscle contraction: In skeletal and cardiac-muscle cells, calcium is an intracellular messenger that triggers contraction of the muscle fibers.

4. Nerve transmission: Calcium plays a central role in depolarization of membranes and nerve transmission.

4

Low dietary intake over time mobilization of calcium from the skeleton to maintain circulating levels risk of osteoporosis.

Chronic use of many antacids, laxatives, and steroids negative calcium balance by reducing absorption and increasing excretion.

Digestive disorders fat absorption unabsorbed fats bind the calcium calcium absorption from diet.

Vitamin D deficiency absorption of diet’s calcium. People with atrophic gastritis (common among the elderly)

loss of gastric-acid secretion absorption of calcium from the diet.

In menopause: loss of estrogen loss of calcium from the skeleton and urinary excretion. Up to 20% of the bone mineral density of can be lost in the 4–6 years around menopause.

Certain dietary components may interfere with absorption and / or retention of calcium e.g. Oxalates (in spinach, rhubarb)- Phytic acid (in whole grains and legumes)- Sodium - Coffee and black tea - Alcohol. Unlike dairy products, calcium from plant sources tends to be less bioavailable because of the presence of fiber, phytic acid, and oxalates.

5

6

High intake of calcium (with vitamin D) may reduce risk of colon cancer by binding with bile salts and certain fatty acids (which may stimulate colonic cell proliferation) protection.

Calcium helps reduce blood pressure in hypertensive patients and risk of hypertensive disorders in pregnancy (pre-eclampsia).

High calcium intakes in childhood and adolescence can reduce or prevent loss of bone calcium associated with aging (Osteoporosis).

Prophylaxis from periodontal disease and dental caries (together with proper oral hygiene).

Replenish calcium stores resulted from disorders of absorption and metabolism e.g. in digestive disorders that produce malabsorption (such as Crohn and celiac disease) as well as in chronic renal failure.

7

8

The body of 70kg contains about 20–30g of Mg: 60% is in the skeleton and about 30% in tissues (particularly in the liver, heart, and muscle).

Magnesium plays an essential role in > 300 different biochemical reactions.

RDA = 300 mg. Therapeutic dose

range = 300 – 1000 mg.

9

Mg plays a central role in energy production reactions in cells (where the breakdown and oxidation of glucose, fat, and proteins require magnesium-dependent enzymes). Mg regulates calcium-triggered contraction of heart and muscles. Mg can produce vasodilation of the coronary and peripheral arteries lower blood pressure. Mg regulates nerve depolarization and transmission by regulating movement of ions (calcium, potassium) through ion channels in nerve membranes. Mg(together with calcium and phosphorus) is important for the structure of bones and teeth.

10

Low dietary intake of magnesium.People with diabetes and hyperparathyroidism.Athletes in strenuous training.Periods of rapid growth, such as pregnancy and

lactation, as well as childhood and adolescence.Chronic use of certain medications: diuretics

(thiazides, furosemide), chemotherapy (cisplatin), cortisone preparations, and laxatives magnesium retention by the body.

Regular high intakes of alcohol increase loss of magnesium.

Intestinal malabsorption (such as inflammatory bowel disease, chronic diarrhea, pancreatic disease) absorption of dietary magnesium.

Atallah F. Ahmed, PhD 11

Diabetes mellitus. Mg deficiency is common in type 1 and type 2 diabetes and may insulin sensitivity and risk of high blood pressure, heart, and eye diseases.

Mg (with vitamin B6) risk of Ca-oxalate stones.

Mg helps risk of arrhythmia and angina pectoris. It can be useful as an adjunct to digitalis, nitrates, and -blocker therapy.

Mg helps control high blood pressure (systolic type) and hypertensive disorders of pregnancy (eclampsia).

Mg helps reduce night leg cramps and abdominal cramps associated with pregnancy and menstruation.

Mg benefits in anxiety, irritability, and insomnia.

Mg helps reduce frequency and severity of migraine.

Mg may help to maintain positive calcium balance and reducing the risk of bone mineral loss and osteoporosis.

12

13

The body contains 30–40g of potassium; 98% is contained within cells, most of it within skeletal muscle.

The 3rd most common mineral in the body after Ca and P.

RDA = 2-3 g. Therapeutic dose range (to reduce risk of high blood pressure, stroke, and heart disease) = 4–5 g/day.

Energy production in cells. Membrane excitability and

transport of all muscle contraction, nerve transmiss-ion, and hormone secretions. Example: propagation of electrical signal through myocardium and contraction of the heart are potassium dependent.

14

Diarrhea and/or vomiting (e.g. in cases of inflammatory bowel disease or gastroenteritis) loss of K+.

Chronic kidney failure excretion of K+ in urine. Strenuous exercise, chronic diets for weight loss loss of

K+. Changes in body pH (both metabolic acidosis and alkalosis)

depletion of K+. Many diuretics (thiazides, furosemide) loss of K+

depletion of K+. Magnesium deficiency leads depletion of K+.

15

In hypertensive people K+ can lower blood pressure by 5–6 and 3–4 mmHg for systolic and diastolic pressure, respectively. It is more effective in older people and African Americans. A diet containing a high K+/Na+ ratio can reduce high blood pressure and risk of stroke. Increasing dietary K+, fiber intake and exercise can produce more regular bowel habits and treat constipation than regular intake of laxatives which lead to K+ depletion from the body. In chronic diarrhea (replace potassium loss). In cardiac arrhythmias due K+ depletion produced by diuretic therapy and/or low dietary K+. People with heart disease and those taking cardiac glycosides and thiazide diuretics should obtain adequate dietary K+.Prolonged agressive exercice or physical activity (particularly in hot weather K+ loss in sweat of up to 10g/day) needs K+ replenish to protect from muscle fatigue, performance drop , muscle cramping and spasms.

16

17

1. Essential in the dietMajor minerals

(more than 100mg/day needed)

2. Trace minerals(less than 100 mg/day needed)

Minerals

18

The body contains ~ 3.8 g for adult man and ~ 2.3 g for woman. About 2/3 iron content is in a functional forms as hemoglobin in blood and myoglobin in muscle. The other1/3 is stored in bone marrow and liver.

Because iron is a powerful oxidant and potentially harmful, it is stored and transported carefully bound to protective proteins and surrounded by antioxidants.

RDAMales = 8 mg/dayFemales = 18 mg/dayPregnant women = 27 mg/dayLactating women = 9 mg/dayVegetarians need 1.8 times as much iron

Therapeutic dose range

= 10-200 mg/day

19

Iron plays a critical role O2 transport from lungs to tissues (60% of body iron is in red blood cells as hemoglobin).

Muscle function (~10% of body iron is in the form of myoglobin in muscle which stores O2 in muscles and releases it to provide energy during physical activity).

Energy production (It is an essential part of mitochond-rial cytochromes that serve as electron carriers in the production of energy as adenosine triphosphate (ATP).

Enzyme function. It is an essential cofactor for several important redox enzyme systems such as:-Cytochrome P450 system in liver that detoxify chemicals and toxins.- Peroxidases and catalases (antioxidant) that protect against free radicals.- Other iron-containing enzymes play roles in production of brain neurotransmitters and thyroid hormone.

20

Best = heme iron or iron prophyrin (animal sources of iron), ~25% absorbed

Poor = non-heme iron or iron-sulfur protein (vegetable sources), ~17% absorbed

All the iron in foods derived from plantsis nonheme iron.

Only foods derived from animal flesh provide heme, but they also contain nonheme iron. Heme accounts for about

10% of the average dailyiron intake, but it is wellabsorbed (~ 25%).

Nonheme iron accountsfor the remaining 90% butit is less well absorbed(~ 17%).

Heme

Key:

Nonheme

21

Iron Absorption-Inhibiting Factors Phytates and fibers from legumes, spinach, grains, and rice

Vegetable proteins in soybeans, legumes, and nuts

Calcium in milk

Tannins and other polyphenols in tea, coffee, and others.

When nonheme iron is consumed with vitamin C at the same meal, absorption of iron increases.

Citric acid and lactic acid from foods, HCl from the stomach, and sugars enhance nonheme iron absorption

Iron Absorption-Enhancing FactorsMFP factor (animal source) enhances the absorption of nonheme iron (of both animal and vegetable source).

22

23

Iron deficiency is prevalent in women and children (50–70% of young, healthy women have some degree of iron deficiency and 6–10% of children are iron deficient).

Growth during childhood, adolescence and during pregnancy sharply increases the need for iron.

Vegetarians: plant based diets contain nonheme iron of low bioavailability.

Drinking large amounts of coffee or tea with meals reduce iron absorption.

Stomach conditions that reduce gastric acid secretion (e.g. atrophic gastritis in elderly, stomach surgery, and chronic use of antacids) reduce iron absorption.

Heavy menstrual bleeding in women and chronic blood loss from G.I.T. (hemorrhoids, small ulcers, irritation from aspirin or other NSAIDs) gradual iron deficiency.

Chronic illness and deficiencies of vitamin A, vitamin B6, and copper reduces the body’s ability to mobilize iron from stores.

RBCs tend to be microcytic and hypochromic

24

25

In treatment of iron deficiency anemia (High doses of supplemental iron + vitamin C).Prevention of iron-deficiency anemia during pregnancy.Fatigue, lack of energy, headache, and concentrating difficulty, due to reduced iron stores, without signs of anemia (Supplemental iron + vitamin C).Learning difficulties in children and adolescents (Increased intake of iron-rich foods together with supplemental vitamin C can be beneficial).Exercise, sport, regular long-distance running and swimming often lead to depletion of iron stores and reduced performance. Replenishing low iron stores will increase maximal oxygen consumption and survival.Recurrent infections in childhood (frequent colds, flu, ear infections) may be a sign of lowered immune resistance due to iron deficiency.

26

27