All-Creatures.org Health Position and Disclaimer
Dr. Mary (Clifton) Wendt,
Get Waisted
April 2014
In the digestion process of animal proteins, the proteins must undergo extensive methylation and hydroxylation. These chemical processes result in the creation of acids. The body rids itself of these excess acids by peeing them out in the urine. But in order to neutralize the acidity of the urine, the body grabs extra calcium from the bones and that’s peed out too—in the same way my mom neutralizes her excess acidity by taking a Tums. The advantage vegans hold is that plants do not create an acid environment in the body and, therefore, the body isn’t stimulated to leach calcium from the bones to neutralize the acid.
Bone is made up of proteins that bind to each other, creating strong
cross links that support the weight of the other structures in the body,
like muscles and organs. There are two types of bone in the human skeleton:
Trabecular bone is found in the inside of bones. When it’s healthy, it looks
like very good Swiss cheese, or like the steel structure of a skyscraper in
the process of being built. The outer layer of bone, the cortex, is made up
of cortical bone. Cortical bone is thicker and denser, and functions like a
strong outer protective shell for the inner latticework.
What keeps bones strong and healthy, and why do some of us suffer from bone
weakness? It all has to do with bone turnover, and that’s a subject keenly
interesting to Dr. David Dempster. He is a bone scientist who has spent 40
years studying bone turnover at Cornell University in upstate New York.
Imagine that you just initiated a running program, and that you’ve
unfortunately developed micro-fractures in your tibia, commonly referred to
as shin splints. I’m going to explain what happens at the cellular level so
that you can connect the boring science to the more exciting implications
for diet. So here goes! Your body releases molecules that are known as local
inflammatory mediators—essentially cells that, like an ambulance, arrive at
sites of inflammation to promote healing, cells such as interleukin-1 and
tumor necrosis factor. These mediators activate the osteogenic precursor
cells—cells that come from bone-forming tissue. These cells then morph into
osteoclasts, which are cells that clean up and sweep away dirty, old bone.
The osteoclasts swing into action and clean the bone. After the osteoclasts
finish their work, they leave behind a resorptive pit, or a space that’s
ready to fill in with fresh new bone. Osteoblasts—osteogenic precursor cells
that have morphed into building cells—go to the site of the resorptive pit
and fill it in with fresh, new bone. The process of building a new bony
surface takes only four to six weeks. Mineralizing that site with calcium
and phosphorus to harden and strengthen the site takes another several
weeks.
In a woman’s premenopausal years, the osteoclastic and osteoblastic
functions are beautifully balanced —when old, dirty bone is identified, it
is cleaned up and promptly replaced with fresh healthy bone. After estrogen
levels decline, however, the osteoclast function—the cells that clean up and
sweep away dirty old bone—increases dramatically, but the osteoblast
bone-building activities get overwhelmed by bone resorption. There are just
not enough osteoblast precursor cells to go around. This results in an
overall loss of bone in the postmenopausal woman, particularly in the first
three years of menopause.
Bones are remarkably responsive, dynamic structures. Trabecular bone, the
inner structure of most bones, turns over at a rate of 22 percent per year.
Cortical bone, that outer hard surface of bones, turns over at a rate of
only 3 percent per year. When a woman undergoes menopause, however, bone
turnover increases by 8 percent for the first three years after the
transition, resulting in a remarkably rapid loss of bone early in the
menopausal transition.
Protecting the bone through healthy exercise and diet becomes critical
during this phase of life. According to Dr. Bonny Specker, the world thought
leader on exercise and bone health, the very best exercise for bone building
is tennis. There’s plenty of acceleration and rapid deceleration (running
and stopping), weighted rotation (swinging the racket) and weight-bearing
exercise (jumping) for the entire skeleton. Increasingly, scientists are
looking not only at the distance or duration of exercise, but at the
acceleration and deceleration that occurs during the exercise. Stopping and
starting, like running or basketball may have more skeletal benefits than
exercising exclusively with yoga or walking.
Mix It Up
If you aren’t a tennis player, identify a number of different activities you
do like to do. Biking is great, but bikers are prone to osteoporosis of the
mid-spine due to lack of use. Walking is great too, but it doesn’t work the
shoulder girdle and upper spine very well. Combining a few different
activities will benefit your entire body’s skeleton and muscle system. This
is why so many excellent personal trainers recommend you do a wide range of
activities through cross training.
Keep Calcium in Your Bones
Remember Dr. Dempster? Turns out he wrote the paper on nutrition and
osteoporosis way back in the 1980s. He studied the function of osteoclasts
in great detail. When osteoclasts get ready to sweep away bone, they adhere
themselves to the surface of the bone. The osteoclast then creates a pocket
of highly acidic fluid between itself and the bone. It is in this highly
acidic environment that the osteoclast works to sweep away damaged bone. Dr.
Dempster’s laboratory work showed that when the acidity of the
microenvironment rose even slightly, the osteoclasts went crazy with
increased activity. The acidic microenvironment theoretically makes their
job of creating a highly acidic pocket much easier. They are able to work
faster to absorb and sweep away bone.
The acidic microenvironment purportedly created by a diet rich in animal
proteins theoretically results in accelerated osteoclastic function,
according to Dr. Dempster’s research. Remember hearing that meat doesn’t
really digest; it just rots in your gut? When a woman eats a diet rich in
animal proteins, this results in a prolonged acidic environment in the gut.
The increased gut acidity results in increased acidity in the blood.
The body’s chemistry becomes vital when talking about bones, but it’s
another one of those subjects that gets complicated fast. Think about it
like this: When my mom gets a sour stomach, she often chews a calcium
carbonate tablet for instant acid indigestion relief, under the trade name
of Tums. This is exactly what the body is doing when it is going to the bone
for calcium salts in an effort to neutralize the acidity created by animal
foods. But how do animal foods create acid?
In the digestion process of animal proteins, the proteins must undergo
extensive methylation and hydroxylation. These chemical processes result in
the creation of acids. The body rids itself of these excess acids by peeing
them out in the urine. But in order to neutralize the acidity of the urine,
the body grabs extra calcium from the bones and that’s peed out too—in the
same way my mom neutralizes her excess acidity by taking a Tums. The
advantage vegans hold is that plants do not create an acid environment in
the body and, therefore, the body isn’t stimulated to leach calcium from the
bones to neutralize the acid.
Recent studies, however, have argued that urinary
acidification/calcification associated with a high protein diet may not be
accurate. These researchers gave women very large doses of animal proteins
combined with a large dose of calcium that was radioactively tagged, so they
could see where the calcium ended up. They noted that the radioactively
tagged calcium ended up in the blood serum and urine after women consumed a
large amount of protein. The researchers concluded that the calcium in the
urine of women consuming a high protein diet actually originates from the
food they are eating, not from their own bones. The research also suggests
that a high protein diet leads to increased calcium absorption—that is the
intestines of omnivores more readily absorb calcium from food.
This study seems to raise more questions than it answers. If a high protein
diet is consumed with high concentrations of calcium, then the body will not
have to look to the skeletal system for additional calcium to handle the
increased urinary acidity. However, if the woman’s diet is deficient in
calcium, as is true in Western diets, then the body will naturally have to
look to the skeleton as a source of calcium. Further study in this area,
with a more realistic combination of a high protein diet with low calcium
ingestion, might provide more insightful on how diet affects skeletal
health.
Not all animal proteins are created equal, according to research by Dr. T
Colin Campbell and Boston nutrition expert Dr. Beth Dawson-Hughes. Meats and
processed dairy products such as hard cheeses generate acid during their
digestion. Liquid milk, however, is alkaline in the body, and does not
promote urinary acidification and calcification like other dairy products.
You still might want to avoid liquid milk for other reasons, but more on
that later. It is not reasonable to issue a blanket warning that all animal
proteins are harmful to your bones.
PPerhaps the most reassuring bit of data arose from a study of Buddhist nuns,
women who were vegans for most or all of their lives. The bone density of
these nuns was measured and compared to the bone density of ordinary women.
It turns out that the nuns had clinically equivalent bone mineral density to
women who drank cow’s milk and consumed nearly twice as much calcium in
their daily diet.
To suggest that dairy products aren’t the healthiest source of dietary
calcium and protein is almost unpatriotic here in the United States. We
Americans grew up as little girls with milk on our cereal at breakfast, a
carton of milk on the corner of our lunch tray and a glass of milk at the
corner of our placemat at dinner. Copious scientific data have made it clear
that we have healthier, safer protein and calcium sources in beans and whole
grains, without the inflammation and acidification risks associated with
animal proteins. While plenty of government programs subsidize meat and
dairy, women have to recognize that the government is often slow to respond
to new information. Women seeking optimal health should focus on the
identification of plant sources of calcium like green leafy vegetables,
whole grains and beans.
Getting to Know Your Skeleton
You can ask your doctor to perform a bone density test to determine the
density of your skeleton. Bone density can be measured by ultrasound, plain
x-ray or a quantitative CT scanning of the vertebrae (back) or femur (thigh)
bone, but the most common method is the use of bone densitometry. The
technology is readily available everywhere, and you don’t even have to
undress to undergo the testing. You can simply lie down on the examination
table while the records your bone density in just a few moments. The
radiation exposure is equivalent to a day in the sun. Most advisory boards
recommend starting bone density measurements at 65 years old, repeating them
as often as necessary based on the bone density measurement, risk for
developing osteoporosis and risks for fracture. For example, the need for
treatment or frequency of testing is different for a healthy gal who has low
bone density, compared to a gal who doesn’t eat properly, smokes, takes
multiple medications and who is at risk of falling because of limited
vision. Your doctor should carefully balance all of the risks and benefits
of therapy before initiating any medical management. You can also use risk
calculators available to your doctor through the National Osteoporosis
Foundation to help determine your risk of fracture more accurately.
What to Do if You’re Diagnosed with Osteoporosis
Osteoporosis treatment is reasonable when diet and exercise fails to control
bone loss, or when bone loss is complicated with fracture. As women age, the
main reasons for loss of independence and transfer to nursing homes are
dementia and bone fracture. Preventing fracture, therefore, is a very
important part of successful aging. To prevent a fall, do the easy things
first. Remove any clutter from the floor and tape down or remove any loose
carpets or rugs that may get caught on the edge of a foot and lead to falls.
Make sure that if you need a walking aid, you use it regularly. If your
doctor thinks you would benefit from using a cane, go ahead and buy a cane
to stabilize your posture, and then use it. It’ll do you no good propped up
against the wall instead of held in your hand.
Long-term treatment with many bone-stabilizing medications is falling under
scrutiny recently, since these medications have been linked to atypical
fracture in the femur and osteonecrosis of the jaw (bone death caused by
poor blood supply). Researchers are concerned that prolonged treatment with
osteoporosis medications may result in the suppression of bone turnover
until the bone is no longer able to properly heal itself by cleaning up and
replacing old, damaged bone. As a result, damaged bone may accumulate, which
increases risk for fracture. If you have been treated for many years with
osteoporosis medications, it may be time to talk to your doctor.
While there is talk of taking a “drug holiday,” where patients stop their
osteoporosis medications for a while, there are no scientific studies to
support that idea.
When considering a drug holiday, it’s important to note that adequate data
on fracture risk is collected in just three short years of study in most
drug trials. If you are osteoporotic at high risk of fracture because of
falls or other chronic disease, it doesn’t take long to experience a serious
outcome, like fracture and disability, from your osteoporosis. If you have
osteoporosis, you are at higher risk for fracture, and given the
consequences of fractures, taking prescribed medications makes a lot of
sense. The FDA does recommend that potent osteoporosis therapy is limited to
three to five years, at which time therapeutic need should be reassessed.
There are new medications and alternatives that don’t have the same level of
risk associated with their administration, and a little subtle change in
your medication, in addition to a great, healthy diet and exercise plan, may
be just the thing you need.
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We began this archive as a means of assisting our visitors in answering many of their health and diet questions, and in encouraging them to take a pro-active part in their own health. We believe the articles and information contained herein are true, but are not presenting them as advice. We, personally, have found that a whole food vegan diet has helped our own health, and simply wish to share with others the things we have found. Each of us must make our own decisions, for it's our own body. If you have a health problem, see your own physician.