Micronutrients: Calcium

1
Micronutrients Calcium

• major component of bones, teeth
• Required for many physiological processes
• Roles of parathyroid hormone, calcitonin
• bone loss begins to increase during young
  adulthood (gt35 years)
• Estrogen and menopause
• designer estrogen called Evista
• lack of calcium gt porous bones (osteoporosis)

2
Calcium, contd.

• daily requirements
• adolescence 1200 mg/day
• non-pregnant, non-lactating women 800 mg/day
• after menopause 1500 mg/day
• typical intake of post-men. women 500 mg/day
• food sources of calcium dairy products, green
  leafy vegetables
• http//www.lowfatweekly.com/calcium_content_in_foo
  ds.htm
• absorption requires vitamin D

3
Osteoporosis

• 80 of osteoporotic individuals are female
• 8 million women, 2 million men in U.S. currently
  suffer from osteoporosis
• 1 out of 2 women will be affected after age 50
  years
• 38 million / day spent on treatment
• Risk factors
• gender, age, smoking, family history, calcium
  intake, sedentary lifestyle, drinking

4
Osteoporosis

• Bones most often affected
• vertebrae, hips, wrists

5
Osteoporosis
6
Iron

• part of hemoglobin
• deficiency fewer red blood cells, decreased
  oxygen availability
• low levels result in iron deficiency anemia
• women susceptible due to monthly blood loss
• daily requirements
• premenopause 50-70 mg/day
• postmenopause 30 mg/day
• foods rich in iron red meat, liver, rice, beans,
  eggs, dried fruit
• http//www.dialadietitian.org/resources/handouts/f
  e-food.html

7
Folic acid

• form of vitamin B (folate)
• foods rich in folic acid
• green leafy veggies, lentils, asparagus,
  broccoli, orange juice, fortified cereals, liver
• important during childbearing years
• may also protect against heart disease, cancer,
  psychiatric disorders
• important for regulating blood homocysteine levels

8
Homocysteine

• metabolite of the amino acid methionine
• can be recycled to form methionine or can be
  degraded into cysteine and excereted
• B vitamins (Vit B12, folate, Vit B6) are required
  for these processes
• Vit B12 and folate participate in recycling of
  homocysteine into methionine
• Vit B6 required for degradation into cysteine
• High levels of homocysteine can adversely affect
  many tissues

9
Dangers of high homocysteine levels

• Correlation between high hcy levels and
  cardiovascular disease
• Increased activation of clotting factors
• Increased atherosclerosis
• Correlation between low folate, high hcy and
  neural tube defects during pregnancy
• Correlation between high hcy levels and
  schizophrenia
• Genetic defects in metabolic enzymes can also
  contribute

10
Phytoestrogens

• Plant compounds that are structurally similar to
  estrogen
• Are weak estrogens or antiestrogens
• Isoflavones, lignans, coumestans
• Present in soy foods, oilseeds (e.g., flaxseed),
  and whole grain cereals
• Cultures in which soy is a regular part of daily
  diet (200 mg/day) have
• Decreased rates of breast, ovarian cancer
• Decreased menopausal symptoms (lt25 vs. 80)
• Decreased cardiovascular disease

11
Isoflavone content of various foods

• Roasted soybeans 162.5 mg
• Textured vegetable protein 138.2 mg
• Green soybean 135.4 mg
• Tofu 33.7 mg
• Soy hot dog 15 mg