Osteoporosis: Causes and Treatments
© 2005 Katherine Poehlmann, Ph.D.
Bone is a protein framework made up mostly of collagen, which also makes up cartilage, skin, hair, and nails. Loss of bone tissue leads to loss of bone mass. Humans have a total of 206 bones. All cortical bones are encased in a thin, tough, protective membrane of tissue called the periosteum, except at the joints where there is a layer of cartilage, an integral part of the process by which bones grow in length. This is called longitudinal growth, occurring at the ends of bones where there are thin disks of cartilage called epiphyseal growth plates. During the years to adulthood, successive layers of cartilage form over existing hard bone. The cartilage itself hardens from the deposits of calcium phosphate, becoming bone. Adult height is reached when the growth plates stop forming.
The outer shell of dense cortical bone
encases the softer inner structure of trabecular bone. In Osteoporosis (OP),
the cortical bone is no longer dense, and cannot hold the structure together.
The
body is in constant build-up/tear-down mode. Special cells called osteoclasts
get rid of old bone; osteoblasts rebuild it. If this process is kept in
balance, there’s no problem. We can offset bone loss by keeping calcium at
optimal levels and by performing weight-bearing exercises.
Of
women over 50, half will suffer fractures due to OP and 1/3 will suffer a
spinal (vertebreal) fracture in later years. Almost as many women die annually
from osteoporosis-related illnesses as die from breast cancer. Death from
complications (pneumonia, blood clots, infections) following bone fractures
makes OP the fourth leading cause of death, following heart disease, cancer,
and stroke.
Bone
mass builds steadily to age 30-35, then loss begins at a rate of 1% per year.
During pregnancy and breast feeding, bone loss increases for women, despite
increased estrogen levels at these times. After menopause, women lose 3% per
year, leveling off to 1% after 7-10 years.
Men
have an advantage over women by losing bone mass at a steady rate of 1%. They
also start the loss process with heavier bone mass.
Bone
Densitometry tests measure bone-mineral mass, essentially the volume of calcium
within the bone tissue. The tests use a photon energy source passed over the
body. Some of these tests are:
·
Dual
Energy Xray Absorptiometry (DEXA) uses two xray beams to measure structure deep
within soft tissue. This is mostly used for hip, wrist or spine. It can measure
total calcium in the body.
·
Dual
Photon Absorptiometry is an older version of DEXA.
·
Single
Photon Absorptiometry measures cortical bone loss as a predictor of OP, used
mainly on the heel, wrist, and forearm;
·
Radiographic
Absorptiometry uses regular xrays on appendages such as the hand;
·
Computerized
Tomography (CT or CAT scan) is used to measure cortical bone separately from
trabecular bone.
·
Quantitative
Computed Tomography (QCT) is a CAT scan applied to the spine.
·
Heel
screening device is based on ultrasound waves rather than xrays. Results are
questionable because the heel bears so much of the body’s weight but the test
can be an indicator of OP elsewhere in the body.
·
Blood
tests can determine whether changes in bone are cause by some other disease,
infection, or nutrient imbalance.
·
Urine
test can measure the efficacy of treatments for osteoporosis.
There are no warning symptoms for OP except shrinking height, a rounded back, spontaneous fractures or fractures resulting from minor bumps, acute back pain around the waistline during routine activities or at rest. If you think you are at risk, ask for tests every few years.
Risk factors for OP are:
· age
(over 45)
· heredity
· race
(Caucasian or Asian)
· calcium-poor
diet
· excessively
thin body
· smoking
· thyroid
dysfunction
· sedentary
lifestyle
· poor
circulation
· taking
antacids containing aluminum
· alcohol
and caffeine consumption
· drinking
more than two sodas per day
· excess
vitamin D intake (sun and/or supplements)
· long
term uncontrolled diabetes
· stricken
with collagen destructive diseases like RA and scoliosis
The parathyroid hormone stimulates
osteoclast activity, helps convert vitamin D to an active form that increases
dietary calcium absorption, and helps the kidneys metabolize calcium. Excess
parathyroid or thyroid hormones can result in bone loss due to overzealous
osteoclast activity. Estrogen and progesterone prevent adrenal hormones from
destroying bone.
The active hormone of vitamin D
(1,25-dihydroxyvitamin D or 1,25-D) performs a vital function in autoimmune
diseases, notably Sarcoidosis. This hormone is critically related to calcium
balance. At levels above 42 pg/ml, 1,25-D starts to stimulate osteoclasts, in
turn causing bone to be resorbed (dissolved) back into the bloodstream, leading
to osteoporosis. (ref 1)
99 percent of body calcium found in bones
and teeth. Dentists are often the first to spot bone loss through dental xrays,
conditions like shifting teeth, pyorrhea, gum disorders and weak jaw function.
This method is 87% effective for detecting spinal bone loss. Routine xrays are
usually part of an annual checkup, so changes in bone mass in the jaw are easy
to track.
Calcium-inhibiting
drugs can hasten the onset of OP. Some of these drugs are:
•
corticosteriods (e.g., prednisone)
• for cardiac irregularities or to prevent seizures (e.g., phenytoin, barbiturate anticonvulsants)
•
for autuimmune disorders and cancer treatments (e.g., methotrexate)
•
after organ transplantation (e.g., cyclosporine A)
•
for endometriosis (e.g., gonadotropin-releasing hormones)
•
some powerful antibiotics (e.g., ciproflaxin)
Substances we consume as part of a daily diet may contribute to OP, such as:
·
caffeine (in drugs, foods, beverages)
·
phosphoric acid in sodas (regular and
decaffeinated)
·
oxalates (asparagus, beet greens, Swiss chard,
dandelion greens, peanuts, summer squash, parsley, rhubarb, spinach)
·
tea, cocoa (contain oxalic acid)
·
excess salt
·
phytates found in some whole grain cereals
·
too much protein (causes acidity – calcium and
phosphorus are leached from bones to serve as a buffer)
Caffeine is a diuretic. It causes us to lose valuable minerals (calcium, sodium, magnesium, and potassium) in the urine. Many prescription drugs and OTC remedies contain caffeine.
Milk presents problems, too (see Milk as a Calcium Source).
Instead, eat nonfat plain yogurt, cheese, calcium-rich vegetables (beans,
broccoli, greens) and fish (salmon, sardines). Use only calcium carbonate
tablets that do not contain aluminum salts.
Use lemon when cooking certain vegetables
listed above to neutralize oxalates. Although fiber is good for the body as a
cleansing “broom” in the digestive tract, it can bind with calcium when
consumed at the same time. Thus the traditional breakfast bowl of cereal with
milk is the least effective way to obtain calcium.
Calcium must be in balance with phosphorus by
a ratio of 2.5 to 1. Consuming more than two sodas introduces a phosphorus
overload, prompting the body to rob calcium from bones to regain the ideal
ratio. Too much phosphorus can unbalance other minerals: copper, zinc,
magnesium, and manganese.
Taking antacids
containing aluminum is risky. The aluminum combines with phosphorus and
calcium, drawing these minerals into the urine and out of the body. This
calcium shortage can’t be made up with supplements. Too much calcium can be
toxic (resulting in kidney stones and/or bone spurs). Prevent bone spurs with
calcium fluoride. Look for Calc. Fluor, homeopathic 6X (ref 2).
Calcium
intake guidelines for women: 1000-1200 mg for pre-menopausal, and 1500-2000 mg
for post-menopausal. Lower numbers are for ERT. (ref 3) Drink lots of fresh,
pure water to flush toxins and encourage cell rejuvenation.
Exercise
is very important to limit the onset (or effects) of OP. New cortical bone is
laid down in concentric circles called Haversian canals. Weight-bearing
exercise (WBE) thickens cortical bone by increasing blood flow within those
canals. As trabecular bone becomes porous during OP, holes form. Correcting
nutrition deficiencies plus an exercise program helps the blood bring extra
nutrients to bone-building cells, and the trabecular holes are gradually
filled.
WBE puts stress on the bones that stimulates bone-building cells to grow supporting tissue for the additional weight. An effective program should include 3 types of exercise: flexibility, aerobic, and WBE (also called resistance training). Examples are weight lifting (free weights with dumbbells), brisk walking, stair climbing, hiking, dancing, skiing, low impact aerobics (step and water), and treadmill. Swimming per se is not WBE, but is good for flexibility and aerobic benefit. Brisk walking at a steady pace 3-5 times per week for 30-60 minutes is excellent. Just be sure you wear shoes that keep good posture and proper body alignment. Build up gradually, aiming to cover 3-4 miles in an hour.
Evidence
is mixed on whether estrogen decreases the risk of hip fractures, but it may
help prevent spine fractures. Estrogen may increase the risk of breast or
endometrial cancer and blood clots.
OP research is ongoing. The so-called
Leisure World Study (ref 4) monitored retirement complex residents over age 70
who had not exercised in the past. These 8600 women and 5049 men were put on a
weight-bearing exercise program. Some participants built measurable bone mass
and significantly reduced risk of hip fracture over the ten years the study was
conducted. Those who benefited most did 1 or more hours per day, compared with
those doing ½ hour or less per day. Current cigarette smokers had significantly
increased risk compared with non-smokers and past smokers who had quit.
In the “Minocycline for Osteoporosis
Study” (ref 5), lab rats grew bone mass with minocycline treatment.
Raised levels of the amino acid
homocysteine have been associated with OP and fracture risks, as well as with
risk of cardiovascular disease, including heart attack and stroke. Researchers
suggest that levels can be lowered by eating more green leafy vegetables and
fortified grains that contain folic acid, as well as upping intake of vitamins
B-6 and B-12. (ref 6)
Osteoporosis is not an inevitable
part of aging. It’s never too late -- or too early -- to think about saving
your precious bones and cartilage.
REFERENCES:
1) Marshall, Trevor G., PhD. “A Review – Vitamin
D and Calcium in Sarcoidosis”, July 5, 2003. See http://www.sarcinfo.com/calcium.htm. Also see Endocrine
Reviews 21 (2): 115-137, “Birth and Death of Bone Cells: Basic Regulatory
Mechanisms and Implications for the Pathogenesis and Treatment of Osteoporosis”
by Stavros C. Manolagas.
2) Veterinary approaches to ailments we share
with animals (sprains, arthritis, bone spurs, etc.) are often effective and
benign. See http://www.todayshorse.com/Experts/CheyanneWest/AskCheyanne7.htm.
3) JAMA
Nov 1992 by Dr. Robert Recker, et al.
4) Epidemiology. 1991 Jan;2(1):16-25. “Exercise and other factors in the prevention of hip fracture: the Leisure World study.” Paganini-Hill A, Chao A, Ross RK, Henderson BE. Conducted by the Department of Preventive Medicine, University of Southern California School of Medicine, Los Angeles 90033-0800
5) Statement of the
Director, National Institute regarding Aging on NIA's FY 1998
Budget, before the House Appropriations Committee,
Subcommittee on Labor, Health and Human Services, Education and Related
Agencies March 4, 1997. National
Institutes of Health, U.S. Dept of Health and Human Services
6) NEJM
Volume 350:2033-2041 May 13, 2004 Number 20.“Homocysteine Levels and the Risk
of Osteoporotic Fracture” by Joyce B.J. van Meurs, PhD, Rosale
Dhonukshe-Rutten, M.Sc., Saskia M.F. Pluijm, PhD, et al.
7) Alan R. Gaby, M.D. Preventing &
Reversing Ostioporosis What You Can Do About Bone Los. 304 pages, index;1994.
Prima Publishing
**************
Dr.
Poehlmann is the author of Rheumatoid Arthritis: The Infection Connection,
available at Amazon.com and major bookstores, or click here to order now.
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