WRITTEN ASSIGNMENT: CALCIUM IN MILK
Instructor:
DR. FIONA HOW NI FOONG
Prepared by:
NAME
MATRIC NO.
EMAIL
MUHAMMAD ARIFFUDIN BIN MASKURI
2019189
pudinmaskuri11@gmail.com
MUHAMMAD AZIM BIN MOHD YUSOF
2016525
azimmamy@gmail.com
AHMAD ZULHADI BIN KAMARI
2017625
aceguanyu011@gmail.com
Calcium functions in our daily live
First and foremost, Calcium is responsible in regulation of energy metabolism.
According to Zemel (2004), high-calcium diets reduce adipocyte lipid accretion and weight
gain during overconsumption of an energy-dense diet and increase lipolysis and maintain
thermogenesis during caloric restriction, resulting in weight loss that is significantly
accelerated. Intracellular Ca2+ regulates adipocyte lipid metabolism and triacylglycerol
storage; increased intracellular Ca2+ causes lipogenic gene expression and lipogenesis to be
stimulated while lipolysis is suppressed, resulting in increased lipid filling and adiposity.
Following that, Calcium plays a crucial role in bone health. Bone is a type of living
tissue that is constantly changing. Bones are continually broken down and rebuilt throughout
one's life, a process known as remodeling which involve two major cells; Osteoblasts acts as
bone-building cells, while Osteoclasts acts as bone-breaking cells. Bones need a lot of calcium
and vitamin D during childhood and adolescence to reach their optimum strength and calcium
content by the age of 30 (Office of Dietary Supplements - Calcium, 2017). After that, bones
gradually lose calcium, but people can help slow this down by taking recommended calcium
doses during adulthood and leading a balanced, active lifestyle that involves weight-bearing
physical exercise such as walking and running.
On top of that, Calcium is also essential in the regulation of blood pressure. As stated
by Villa-Etchegoyen et al. (2019), Calcium intake can control blood pressure by causing
vasoconstriction in vascular smooth muscle cells and raising vascular volume through the
renin–angiotensin–aldosterone system (RAAS). Low calcium intake lowers plasmatic calcium
concentration, which triggers the secretion of parathyroid hormone (PTH) and parathyroid
hypertensive factor (PHF), calcitriol synthesis, as well as the activation of renin–angiotensin–
aldosterone system (RAAS). Then, through the angiotensin II type I receptor pathway and
adenylate cyclase pathway in vascular smooth muscle cells (VSMC), angiotensin II and
calcitriol will boost the intracellular calcium concentration. Vasoconstriction occurs as [Ca2+]i
rises, resulting in increased peripheral vascular resistance and blood pressure.
Physical and Chemical Properties of Calcium
Calcium is one of the main elements that can be found in milk. This element is originated
from the group 2A (or IIA) of the periodic table or commonly known as alkaline earth metal.
It has an atomic number of 20 with relative atomic mass around 40.078 u. Calcium is the
world's fifth most abundant material, accounting for 4.1 percent of the planet's crust. It is not
existing naturally as one-unit atom but occurs abundantly as a compound in nature such as
limestone (calcium carbonate), gypsum (calcium sulphate), fluorite (calcium fluoride) and
apatite (calcium chloro- or fluor-phosphate). Dissolved calcium bicarbonate also can be found
in hard water. Stalactites and stalagmites develop as water filters through the ground and enters
a cave. For the appearance, calcium exists naturally as a silvery-white, soft metal that reacts
with water and dissolves quickly in air. Just like the other metals, it has the same physical and
chemical properties with the other metals such as lustrous, good conductors of heat and
electricity, malleable, lose electron easily and good reducing agents. It has a boiling point of
1484⁰C and a melting point of 842⁰C with density around 1.54 g/cm3
This element has chemical properties that similar with all elements from the group 2A.
This group is second most reactive metals after group I because all elements in this group
releases 2 electron in s-orbital of its valence electron to form 2+ ions. Within the group,
Calcium is located at the third place between magnesium and strontium down the group.
Reactivity of group 2A increases down the group so it shows that calcium is more reactive than
beryllium and magnesium but less reactive than strontium, barium and radium. Calcium reacts
steadily with water at room temperature but without ignition to form calcium hydroxide that
dissolves in water as a soda and hydrogen gas according to the following reaction mechanism:
Ca (s) + 2H2O (g) -> Ca(OH)2 (aq) + H2 (g)
All elements from group 2A react with oxygen to form metal oxide. In this case, calcium
readily attacked by air to form white calcium oxide or commonly known as quicklime.
Ca (s) + O2 (g) -> 2CaO (s)
Calcium metal is easily dissolved in either concentrated or diluted acid to form aqueous
calcium halide and hydrogen gas. For example, calcium reacts with hydrochloric acid to form
calcium chloride and hydrogen gas based on the following equation:
Ca (s) + 2HCl (aq) -> Ca(Cl)2 (aq) + H2 (g)
The effect of low calcium level to our body
Calcium is one of the important elements needed in our body because it helps to build
and maintain healthy teeth and bones. Unfortunately, our body doesn’t produce calcium on its
own. It only gets the calcium through the food that we eat such as milk and green leafy
vegetables or from the supplements that we take. If we don’t consume calcium in a certain
period of time, it will cause harm and lead our body to develop hypocalcemia. Hypocalcemia
is a condition in which the liquid component of the blood, called plasma, has lower-thanaverage calcium levels. The normal range for calcium levels is 2.1–2.6 mmol/L (8.8–10.7
mg/dl, 4.3–5.2 mEq/L), with levels less than 2.1 mmol/l being considered hypocalcemia.
There are a number of factors that have been identified as potential causes of
hypocalcemia in people, and the risk of calcium deficiency rises as they get older. To begin
with, the hormone disorder hypoparathyroidism may result in calcium deficiency. This disorder
causes a lack of parathyroid hormone, which regulates calcium levels in the blood.
Hypocalcemia can also be caused by a vitamin D deficiency. Our bodies can absorb calcium
with the help of vitamin D. Calcium is needed for the development of solid, healthy bones.
Bones that are deficient in vitamin D and calcium cannot develop properly in childhood and
can lose mass, become brittle, and break easily as adults. Next, the decrease in the hormone
estrogen during menopause causes a woman's bones to thin more quickly. In order to minimize
the risk of osteoporosis and calcium deficiency disease during menopause, women should
increase their daily calcium intake.
We need to examine our body to identify the symptoms that might lead us to
hypocalcemia and get the treatments as soon as possible to prevent it from become more worse.
The symptoms that we might get are depression, hallucinations, muscle cramps and easy
fracturing of the bones. Fortunately, we were able to avoid hypocalcemia in our bodies. This is
due to the fact that prevention is preferable than cure. Firstly, we need to take the right amount
of calcium and vitamin D every single day. Calcium aids in the formation and maintenance of
bones, while vitamin D assists in the absorption of calcium by the body. There are a lot of food
that rich in vitamin D which can increases the rate of calcium absorption in our blood such as
salmon, fortified orange juice and eggs. There are several lifestyle improvements we can make
to improve bone health in addition to maintaining healthy calcium and vitamin D levels such
as maintaining a healthy body weight, exercising regularly and avoid limiting alcohol
consumption.
References
1. Kahn, A. (2018, July 20). Hypocalcemia (Calcium Deficiency Disease). Healthline;
Healthline Media. https://www.healthline.com/health/calcium-deficiencydisease#prevention
2. Fong, J., & Khan, A. (2012). Hypocalcemia: updates in diagnosis and management for
primary care. Canadian Family Physician Medecin de Famille Canadien, 58(2), 158–162.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3279267/
3. Barhum, L. (2020, December 7). What happens when calcium levels are low?
Medicalnewstoday.com; Medical News Today.
https://www.medicalnewstoday.com/articles/321865#symptoms
4. Villa-Etchegoyen, C., Lombarte, M., Matamoros, N., Belizán, J. M., & Cormick, G. (2019).
Mechanisms Involved in the Relationship between Low Calcium Intake and High Blood
Pressure. Nutrients, 11(5), 1112. https://doi.org/10.3390/nu11051112
5. Zemel, M. B. (2004). Role of calcium and dairy products in energy partitioning and weight
management. The American Journal of Clinical Nutrition, 79(5), 907S912S.
https://doi.org/10.1093/ajcn/79.5.907s
6. Science, M. (2017, July 17). Facts about calcium, and the reaction of calcium with oxygen.
MEL Science; MEL Science. https://melscience.com/GB-en/articles/facts-about-calciumand-reaction-calcium-oxygen/