Osteoporosis
About 10 million adults in the United States have osteoporosis, and
another 34 million have low bone mass that places them at risk for developing
osteoporosis (Norqvist, p.5). The growth of this bone disease is estimated to
grow at an alarming rate. According to the International Osteoporosis
Foundation half of all Americans over age 50 could be at risk for this condition
by 2020 (Norqvist, 5). Seventy percent of people with osteoporosis are women
(Davis p. 6). Men start with higher bone density and lose calcium at a slower
rate than women; which is why their risk is lower. However, older men are also
at risk for osteoporosis (Norqvist, p. 4).
Osteoporosis is a disease of bones that leads to an increased risk of
fracture. With osteoporosis, the bone mineral density is reduced, bone
microarchitecture deteriorates, and the amount and variety of proteins in bone
are altered and/or decreased (Gropper & Smith, p. 450). The deterioration of
bone tissue and mineral density results in fragile bones and increases the risk
for bone fractures (Gropper & Smith, p. 450).
From birth to adulthood, bones grow in length, width, strength, and
hardness. Bones in different parts of our bodies grow at different rates due to
weight-bearing and physical activity stresses placed upon them (Jundt, 2010).
This stress on the bones causes growth (Jundt, 2010).
There is a change through life in bone replacement. For people under
age 30, bone replacement of old bone with new is constant ( Jundt, 2010).
After the age of 30, bone replacement slowly decreases, leading to eventual loss
of bone and strength (Jundt, p. 1). The total amount of bone then decreases,
and osteoporosis may develop as a result (Jundt, p. 1).
There are two types of osteoporosis. Primary osteoporosis is the most
common type of osteoporosis. It can be age-related and associated with the
postmenopausal decline in estrogen levels, or related to calcium and vitamin D
deficiencies (McPhee, 2001). Secondary osteoporosis is osteoporosis caused by
other conditions, such as hormonal imbalances, diseases, or medications (such
as corticosteroids or anti-seizure drugs) (McPhee, 2001).
Diagnosis of osteoporosis is based on a measurement of bone mineral
density, primarily by dual energy X-ray absorptiomentry (DEXA) (Gropper &
Smith, p. 451). DEXA scans and measures bone mineral contents of various
regions of interest (Gropper & Smith, p. 451). Bone mineral density represents
the average concentration of minerals per unit area (Gropper & Smith, p. 451).
Development for osteoporosis can be caused by many factors, such as
aging, gender, genetics, hormones, lack of physical activity, diet, calcium
mineral depletion, and many other factors.
Women have a greater risk for developing osteoporosis than men. According to
the International Osteoporosis Foundation (IOF); osteoporosis affects about
200 million women worldwide (Nordqvist, p. 2).
According to the National Institute of Arthritis and Musculoskeletal and
Skin Diseases, osteoporosis statistics show a greater burden for women in the
following ways:
 68 percent of the 44 million people at risk for osteoporosis are women.
 One of every two women over age 50 will likely have an osteoporosis
related fracture in their lifetime.
 75 percent of all cases of hip osteoporosis affect women.
The ovaries are the main source of estrogen production, and it has a
positive affect on bone formation and mineralization (Gropper & Smith, p. 451).
Estrogen concentrations decrease in women who undergo under surgical
ovariectomy, as well as in some young athletes, those who have eating
disorders, and around the time of menopause (Gropper & Smith, p. 451). In
general, estrogen deficiencies increase the risk for developing osteoporosis
unless estrogen levels can be restored (Jundt, 2010).
Because of the well-known affects of estrogen in bone formation and
mineralization, many health care providers recommend estrogen replacement,
such as oral contraceptives (Jundt, 2010). Oral contraceptives in older women
can reduce bone fraction and improves bone mineral density (Hubar, 2005).
People’s diet has a lot to do with the development of osteoporosis. Again,
many other factors and cofactors play in the development of osteoporosis.
Certain types of foods can help reduce or develop osteoporosis. Calcium,
potassium, vitamins K, C, and D all have a great impact on the stimulation of
bone synthesis and the prevention of osteoporosis.
Another factor that contributes to the development of osteoporosis is
inadequate calcium intake during childhood and adolescence.
A low intake of calcium impairs bone development and may prevent the
attainment of optimal peak bone mass during early adulthood. In older adults,
inadequate calcium intake accelerates bone loss and likely contributes to the
development of osteoporosis (Gropper & Smith, p. 428). Sources of calcium
include dairy products, salmon, sardines, clams, oysters, turnip, broccoli,
cauliflower, kale, legumes, nuts and fortified products with calcium; such as
orange juice and bread. The Adequate Intake (AI) for calcium is 1000 mg.
(Gropper & Smith p. 435). A brief explanation of calcium absorption operates
primarily in the duodenum and proximal jejunum, and is regulated by calcitriol
(Gropper & Smith, p. 427). This process occurs in the small intestine and
accounts for about 60% of total calcium absorption (Gropper & Smith, p. 427).
Calcium absorption in adults average about 25% to 30% (Gropper & Smith
p.427). Calcium absorption from calcium supplements differs from 27% to
39%, depending upon the kind of calcium salt used in the supplements
(Gropper and Smith, p. 427). Our bodies tend to absorb calcium better when
ingested with food (Gropper & Smith, p. 428).
Vitamin D improves bone mass and bone mineral density, and also aids
to the absorption of calcium (Gropper & Smith, 451). Vitamin D, also known
as calciferol, is associated with skeletal growth and strong bones
(Nordqvist, p. 2). Dietary vitamin D originates from some animal sources, such
as beef liver, eggs, herring, salmon, tuna, sardines, cheese, butter, milk,
yogurt, cheese, butter and fortified products with vitamin D (Gropper & Smith,
p. 391). The AI for vitamin D is 800 IU (Gropper & Smith, p. 398). Dietary
vitamin D requires no digestion, and is absorbed by a micelle (micelles allow
non-soluble lipid products to mix with chyme and travel through the small
intestines) (Gropper & Smith, p. 392). About 50% of vitamin D ingested is
actually absorbed ( Nordqvist, p. 5).
Another way that our bodies can obtain vitamin D is from the steroid,
5,7- cholestradienol, better known as 7-dehydrocholesterol (Gropper & Smith,
p. 392). During exposure to sunlight, photons from the sunlight penetrate into
the epidermis and dermis. Skin cells absorb the photons and the process of
synthesizing vitamin D begins (Gropper & Smith, p. 392).
Protein is another vital nutrient for normal skeletal development.
Insufficient protein intake during growth can severely impair bone development
in terms of both size and strength (Gropper & Smith, p.183). In addition to
building strong bones during growth, protein is also important for maintaining
bone mass as you age. According to the International Osteoporosis Foundation
(IOF), clinical research has found that elderly men and women with lower
protein intakes have greater rates of hip and spine bone loss than seniors who
consume higher amounts of protein. About 40% of the body’s protein is found
in muscle, and skeletal muscle mass represents about 43% of the body’s mass
(Gropper & Smith, p. 228). The Recommended Dietary Allowance (RDA) for
protein for adults is 0.8 g of protein per kg of body weight per day (Gropper &
Smith, p. 242). According to IOF, protein supplements have been shown to
benefit clinical outcomes in older adults when administered after surgery to
repair a bone fractures (Nordqvist, p. 3). Some studies have shown that protein
can help reverse bone loss from aging ( Nordqvist, p. 6).
Vitamin C synthesizes hydroxylysine and hydroxyproline, which
synthesizes the triple helix formation of collagen; which is one of the main
proteins in bone (Gropper & Smith, p. 451). Other proteins found in bone are
osteocalcin and the matrix GLA protein (Gropper & Smith, p. 451). These
proteins also depend on the vitamin K for proper function. Vitamin C is
primarily found in fruit and vegetables such as asparagus, papaya, oranges,
cantaloupe, cauliflower, broccoli, brussels sprouts, green peppers, grape fruit,
kale, lemons, and strawberries. The adult RDA for vitamin C is 90 mg.
(Gropper & Smith, p. 311).
Magnesium Recommended Dietary Allowance (DRA) or Adequate Intake
(AI) is 400 mg. (Gropper & Smith, p. 447). The human body contains about
25g of magnesium, of which approximately 50% to 60% is located in bone
(Gropper & Smith, p. 443). Magnesium that does not function as part of bone
is primarily found in skeletal muscle (about 25%), as well as extracellular
fluids, soft tissues, and in organs; such as the liver and kidneys (Gropper &
Smith, p. 444). Magnesium is absorbed through the small intestine.
Magnesium absorption can be improved with vitamin D. Magnesium is found
in many varieties of food, such as nuts, legumes, whole grain cereals, green
leafy vegetables, halibut, milk, yogurt, and even in water (Gropper & Smith, p.
443).
Inadequate intake of vitamin K limits the function of osteocalcin and
matrix GLA proteins, which lowers binding to calcium and limits bone
mineralization (Gropper & Smith, p. 412). Osteocalcin, which needs to be
chemically altered through the process of carboxylation, is a protein especially
linked to bone mineral density (Gropper & Smith, p. 412). Since vitamin K is
required for proper utilization of the carboxylase enzyme (an enzyme that
allows carboxylation of the osteocalcin proteins in our bone), vitamin K can
restore these bone proteins to their proper place in our bone structure and
strengthen the composition of the bone (Gropper & Smith, p. 412). Vitamin K is
absorbed in the small intestine. Vitamin K is found in leafy green vegetables,
oils and margarines from plants. The AI for vitamin K in adults is 90 mcg
(Gropper & Smith, p. 409).
Everyone loses bone mass as we age, but there are lifestyle factors that
can slow the process; and others that can speed it up. There are many lifestyle
factors that can contribute to the development of osteoporosis, but here are a
few examples: foods that promote acidosis, smoking, excessive alcohol intake,
and lack of exercise.
Acidic blood pH is another contributor to osteoporosis. Acidic blood pH
promotes demineralization of bone (Gropper & Smith, p. 452). Acidic blood pH
is produced by an abundance of foods that produce acids; referred as acid ash
(Gropper & Smith, p. 452). Acid ash is produced within the body through the
ingestion of certain types of food, such as meat, eggs, fish, and grains (Gropper
& Smith, p. 452).
Consumption of foods that produce acid ash promotes the oxidation of
the sulfur containing amino acids. Bicarbonate is known for neutralizing
acidosis in the blood; it provides buffers that neutralize acidosis (Gropper &
Smith, p. 452). Diets containing fruit and vegetables rich in magnesium,
potassium, and citrate provides acid/base balance, bone metabolism, and
mineral density. Supplements do not have the same affects that whole foods
have on our metabolism (Nordqvist, 2009).
Recent studies have shown that there is a direct relationship between
tobacco use and decreased bone density. In addition, most studies on the
affects of smoking suggest that smoking increases the risk of having a fracture
(Davis, 2010). The longer you smoke, the greater your risk of fracture in old
age. Some negatives affects of smoking are mentioned below:
 Smokers who fracture may take longer to heal.
 Significant bone loss has been found in older women and men who
smoke.
 Studies suggests second hand smoke exposure during youth may
increase the risk of developing low bone mass.
 Women who smoke often produce less estrogen, and tend to
experience menopause earlier than nonsmokers.
 Quitting smoking appears to reduce the risk of low bone mass and
fractures.
Alcohol consumption is another lifestyle that can affect the health of
bone mass density. Excessive alcohol interferes with the balance of calcium. It
also increases parathyroid hormone (PTH) levels; which, in turn, reduce the
body’s calcium reserves (Davis, 2010).
In addition, heavy drinking can cause hormone deficiencies in men and
women (Davis, p. 5). Men with alcoholism tend to produce less testosterone;
testosterone is linked to the production of osteoblasts (the cells that stimulate
bone formation) (Davis, p. 5). In women, chronic alcohol exposure often
produces irregular menstrual cycles; a factor that reduces estrogen levels,
increasing osteoporosis risk (Davis, p. 6). Also, cortisol levels tend to be
elevated in people with alcoholism (Davis, p. 6). Cortisol is known to decrease
bone formation and increase bone breakdown (Davis, p. 7).
A sedentary lifestyle weakens the bones and reduces the stimulation
bone replacement (Jundt, 2010). People who spend a lot of time sitting have a
higher risk of developing osteoporosis than active people (Jundt, 2010). Any
weight bearing exercise is beneficial for your bones, since this stimulates
growth and strength ( Jundt, 2010). Walking, running, jumping, dancing, and
weightlifting seem particularly helpful for creating healthy bones.
As you can see, the development of osteoporosis involves many factors.
Being a woman is one factor, since women’s bone mass is less than males.
Menopause also plays a significant role in women’s health, since the decrease
of estrogen affects women’s bones (estrogen supplements are recommended).
We saw how important it is to have adequate intakes of calcium and vitamins
C, K, and D. Besides calcium and the vitamins mentioned, people must
consume a variety of foods to nourish our bodies in a proper way. We learned
that minerals and vitamins depend on one another for proper function and
absorption. Vitamin D deficiency appears to affect people’s health, since
vitamin D role is very complex, it helps too keep the bones healthy, helps with
absorption, and helps to metabolize or act efficiently other vitamins. Vitamin D
may have other roles in our body but further research needs to be done. It is
believed that vitamin D deficiency is the cause of many types of cancers in now
days. So it is very important to have an adequate intake of vitamin D to
prevent illnesses related with the inadequate intake of such a important
vitamin. Eating “whole foods” and fruits and vegetables may help people from
developing osteoporosis. Since many people now substitute whole foods with
processed foods, many of these foods have no nutritional value at all. From
whole foods we can obtain the essential nutrients that our bodies need. Taking
supplements is also a good option to stay healthy. But many times
supplements do not work as effectively as whole foods. Avoiding foods that
promote acidosis should also be considered. Lifestyle also has a lot to do with
our health. Exercising is very important, since weight-bearing and physical
activity stress placed upon the bones stimulate growth, strength, and promotes
stronger bones. Alcohol and smoking affects the development of healthy bones,
so these unhealthy habits must be removed from people’s life styles; especially
as people start aging. We live in a time where people are forgetting what
healthy habits and healthy foods are. The consumption of processed foods is
on the rise in many households and their nutritional value cannot be compared
with that of whole foods.
I personally believed that processed foods have a lot to do with many
diseases that we deal with today. Of course many other factors should be
considered too, since every individual gets affected in different ways.
References
Davis Jeanie. (2010, June 21). Osteoporosis. WebMD. Retrieved from
http://www.webmd.com/osteoporosis/features/alcohol?page=2
Hubar Coburn. (2005, October 16). Hormone replacement and
Osteoporosis. emedecine health. Retrieved from
http://www.emedicinehealth.com/hormone_replacement_and_osteoporosis/pa
ge9_em.htm
Jundt, Rob. (2010, March 16). Bone Growth, Bone Health, and
Osteoporosis. Hub Pages. Retrieved from
http://robjundt.hubpages.com/hub/Information-on-Osteoporosis
McPhee, Joan. (2001). Osteoporosis: Risk Factors. Project Aware.
Retrieved from http://www.project-aware.org/Health/Osteo/osteo-risks.shtml
Nordqvist Christian. (2009, August 24). What is vitamin D? What are the
benefits of vitamin D? Medical News Today. Retrieved from
http://www.medicalnewstoday.com/articles/161618.php
Nordqvist Christian. (2009, June 28). “What is Osteoporosis? What
causes Osteoporosis?” Medical News Today. Retrieved from
http://www.medicalnewstoday.com/articles/155646.php.
Sareen S. Gropper and Smith L. Jack. (2009). Advanced Nutrition and
Human Metabolism. Sixth Edition. Belmont CA. Print