This presentation focuses on calcium intake and calcium deficiencies. Calcium is essential for building strong bones and teeth and maintaining bone density. It is also important for nerve and muscle function. The recommended daily intake varies depending on age and physiological state. Dietary sources of calcium include dairy products, leafy greens, fish, and fortified foods. Calcium balance is regulated by hormones like parathyroid hormone and calcitonin. Deficiencies can increase the risk of osteoporosis and bone fractures.

1. Ken-Won Miller
Howard University
Nutrition Care Management 1
Dr. Castor

2. Introduction

 This presentation will focus mainly on the role of
calcium intake and the manifestations of calcium
deficiencies.

3. Nutrients

 Nutrients are essential and all play a key role to
survival of the human organism.
 Water
 Energy yielding nutrients
 Carbohydrates, Protein, Lipids (Fat)
 Vitamins (organic)
 Fat soluble, Water soluble
 Minerals (inorganic)
 Macro, Trace

4. Minerals

Macro-minerals Trace minerals.
 Calcium  Manganese
 Phosphorus  Copper
 Magnesium  Iodine
 Sodium  Zinc
 Potassium  Cobalt
 Chloride  Fluoride
 Sulfur  Selenium

5. What is Calcium

 Calcium is the most abundant mineral in the body
 This mineral is naturally found in foods, added to some,
available as a dietary supplement, and present in some
medicines
 Most of the body’s calcium is found in bones and teeth.
 Estimated to be 99% of calcium in the body
 Approx 1.5-2% of the body weight
 An adequate intake helps grow a healthy skeleton in
early life and minimize bone loss later in life

6. Calcium in Bones

 Calcium salts form crystals called hydroxyapatite on
a matrix of the protein collagen.
 Mineralization of calcium, phosphorus, and other
minerals crystallize and harden the bones.
 The bones gain strength and rigidity as they harden.

7. Calcium in Bones

 Bones are not like solid rock
 Bones gain and lose minerals continuously in an
ongoing process of remodeling.
 The balance between bone resorption and deposition
changes with aging.
 The lack of homeostasis can lead to manifestations of
clinical problems and cause a disease state.

8. Calcium in Body Fluids

 %1 of the body’s calcium circulates in the fluid as
ionized calcium that is vital to life.
 The serum calcium is highly regulated and doesn’t
fluctuate with variations in dietary intakes
 Calcium also activates a protein called calmodulin
 Calmodulin (a inactive protein) is activated by calcium
 It then becomes a messenger that tells other proteins
what to do and serves as an interpreter for hormone and
nerve mediated messages arriving at cells

9. Calcium in Body Fluids

 vascular contraction and vasodilatation
 muscle function
 nerve transmission
 intracellular signaling
 hormonal secretion
 Role in maintaining normal blood pressure

10. Recommended Dietary Allowance (RDA):

RDAs for the amounts of calcium required for bone health and to maintain adequate rates of calcium retention in healthy people.
Table 1: Recommended Dietary Allowances (RDAs) for Calcium [1]
Age Male Female Pregnant Lactating
0–6 200 mg 200 mg
months*
7–12 260 mg 260 mg
months*
1–3 years 700 mg 700 mg
4–8 years 1,000 mg 1,000 mg
9–13 years 1,300 mg 1,300 mg
14–18 years 1,300 mg 1,300 mg 1,300 mg 1,300 mg
19–50 years 1,000 mg 1,000 mg 1,000 mg 1,000 mg
51–70 years 1,000 mg 1,200 mg
71+ years 1,200 mg 1,200 mg
* Adequate Intake (AI)

11. Foods that Contain Calcium

 Calcium is found in a variety of foods.
 Dairy Foods
 Milk, yogurt, and cheese are the most popular choice in the US.
 Leafy Greens
 Kale, broccoli, and Chinese cabbage are vegetable source
 Fish
 Canned sardines and salmon
 Most grains (such as breads, pastas, and unfortified cereals),
while not rich in calcium, add significant amounts of calcium to
the diet because people eat them often in large amounts.
 Fortified foods
 Breakfast cereals, fruit juices, soy(Silk) and rice beverages, and
tofu.

12. Medicines that Contain Calcium

 The two main forms of calcium in supplements are
carbonate and citrate
 Calcium carbonate is found in some over-the-counter
antacid products, such as Tums® and Rolaids®.

13. Calcium Balance

 Homeostasis of calcium is one of the body’s most
important priorities.
 Bone tissue is used as a reservoir and a source of calcium,
to maintain constant concentrations of calcium in muscles,
blood, and intercellular fluids.
 Vitamin D and other hormones play a essential role as
well in balancing levels
 Three organs play a key role in calcium levels
1. The intestines
2. Bones
3. Kidneys

14. Calcium Balance

 Parathormone (Parathyroid hormone)
 A hormone from the parathyroid glands that regulates
blood calcium by raising it when levels fall too low
 Calcitonin
 A hormone from the thyroid gland that regulates blood
calcium by lowering it when levels rise too high

15. 

16. Absorption of Calcium

Calcium is absorbed by all parts of the small
intestine
Two mechanisms of absorption
 Active transport and passive diffusion
It is best absorbed in an acidic medium
Lactose and vitamin D enhances calcium
absorption
The efficiency of absorption decreases as
calcium intake increases

17. Likelihood of Deficiency

 Dietary surveys indicate that many people do not meet the
Adequate Intake for calcium, especially women
 Consuming foods to maintain adequate vitamin D status
improve absorption
 Dietary inadequacy is not likely if protein and calcium intake
are adequate
 Stimulants in coffee and tea can discreetly increase calcium
excretion and reduce absorption in the GI tract
 Phytic acid found in whole-grain breads can decrease
availability

18. Lab Values for Nutritional
Assessment

 The normal levels for ionized (free) Ca2+
 4.64-5.28 mg/dL
 The normal levels for total serum Ca2+ (bound and
unbound)
 8.6-10 mg/dL
 Status is related to many factors, including vit D, vit
K, phosphate, parathyroid function, and medications

19. Lab Values for Nutritional
Assessment

 Hypercalcemia (High Calcium Levels)
 Associated with endocrine disorders, malignancy, and
hypervitaminosis D
 Hypocalcemia (Low Calcium Levels)
 Associated with Vit D deficiency and inadequate hepatic or
renal activation of Vit D, hypoparathyroidism, magnesium
deficiency, renal failure, and nephrotic syndrome

20. Hypoparathyroidism

 Hypoparathyroidism is the
result of a decrease in
production of parathyroid
hormones by the parathyroid
glands located behind the
thyroid glands in the neck.
 Usually occurs after a surgery
where the parathyroid glands
are removed.
 The result is a low level of
calcium in the blood or
hypocalcemia.

21. Assessment Tools

 Dual-Energy X-ray absorptiometry (DXA) is thought to be
one of the best tools for assessing bone mineral density
 Very important in early detection, treatment, and
monitoring of osteoporosis
 Preferred approach for measuring BMD
 Measures bone mineral content at axial and appendicular sites
 Monitors changes over time
 Low radiation exposure
 Superior quality control procedures
 Computerized tomography (CT) scans measure variances
in tissue density. This method is less precise and accurate
than DXA

22. Osteoporosis (Adult
Bone Loss)

 Disease in which the bones become porous and
fragile due to a loss of minerals
 Bone strength is a function of two factors
 Bone mineral density and bone quality
 BMD is determined by peak bone mass and BQ
relates to bone architecture, bone turnover,
mineralization, and the accumulation of damage to
the bone
 Peak in bone mass= late 20’s early 30’s

23. Classification

 Primary-not related to other disease
 Mostly seen in middle aged females and older
men/females
 Males have greater bone mass
 Secondary-identifiable cause other than age or
menopause is present
 Cushing’s syndrome, myeloma, hyperthyroidism,
amenorrhea, medicines( thiazide diuretics and heparin)

24. Osteoporosis

• Leads to a greater risk of fractures
• Fractures in the hip, vertebrae, pelvis,
humerus, distal forearm
• Females more likely to have fractures

25. Five Steps to Optimize Bone Health

1. Maintain a balance diet rich in calcium and vitamin
D.
2. Participate in regular, weight-bearing exercise.
3. Practice a healthy lifestyle with no smoking or
excessive alcohol intake
4. Talk to health care professional about bone health
5. If indicated, obtain bone mineral density testing
and take medication, if appropriate

26. In conclusion

 Calcium is the most abundant mineral in the body
and is mostly found in bones and teeth.
 %1 of the body’s calcium circulates in the fluid as
ionized calcium that is vital to life and homeostasis
 Many people become deficient in calcium especially
those suffering from illness and the elderly
 It is important for dietitians to thoroughly evaluate
patients for calcium defiency and provide
nutritional intervention if needed.

27. References

 Chung M, Balk EM, Brendel M, et al. Vitamin D and Calcium: A Systematic Review
of Health Outcomes. Rockville (MD): Agency for Healthcare Research and Quality
(US); 2009 Aug. (Evidence Reports/Technology Assessments, No. 183.) 1,
Introduction. Available from: http://www.ncbi.nlm.nih.gov/books/NBK32605/
 National Institutes of Health. Optimal calcium intake. NIH Consensus Statement:
1994;12:1-31. [PubMed abstract]
 2 Overview of Calcium." Dietary Reference Intakes for Calcium and Vitamin D.
Washington, DC: The National Academies Press, 2011.
 Ross AC, Manson JE, Abrams SA, Aloia JF, Brannon PM, Clinton SK, Durazo-Arvizu
RA, Gallagher JC, Gallo RL, Jones G, Kovacs CS, Mayne ST, Rosen CJ, Shapses SA.
Clarification of DRIs for calcium and vitamin D across age groups. J Am Diet Assoc.
2011 Oct;111(10):1467. [PubMed abstract]
 U.S. Department of Agriculture, Agricultural Research Service. 2011. USDA National
Nutrient Database for Standard Reference, Release 24. Nutrient Data Laboratory Home
Page,http://www.ars.usda.gov/ba/bhnrc/ndl.