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Q: Phosphorus -- in Soda, Calcium Supplements and Diet ( Answered 5 out of 5 stars,   1 Comment )
Subject: Phosphorus -- in Soda, Calcium Supplements and Diet
Category: Health > Medicine
Asked by: happytobeme-ga
List Price: $10.00
Posted: 13 May 2005 06:48 PDT
Expires: 12 Jun 2005 06:48 PDT
Question ID: 521264
I'm hoping someone can help me understand the following two
potentially conflicting statements:

~~The calcium supplement Posture-D is said by some to be superior to
other supplements because its calcium phosphorus allows for better
bone building.

~~Soda and other like beverages are said to be "bad" to your bones
because their phosphorus (phosphoric acid) limits the bones ability to
absorb calcium.

I am confused -- is phosphorus good or bad (knowing that too much of
anything is almost always bad)?

Is there a difference in the phosphorus found in a supplement like
Posture-D and that in soda?

What about phosphorus in an ordinary diet (for example, meat).

I have been told to eliminate soda but to take the Posture-D
supplement.  These two seem conflicting to me.  I'd much rather be
able to keep drinking diet pepsi and take a calcium supplement without
phosphorous (like Citracal).  I also wonder how an ordinary diet with
one serving of red meat or chicken a day could play into the equation.

Thanks in advance for your assistance!

Best regards,

Subject: Re: Phosphorus -- in Soda, Calcium Supplements and Diet
Answered By: crabcakes-ga on 13 May 2005 14:22 PDT
Rated:5 out of 5 stars
Hello Happytobeme,

I'm starting with the question about soda pop first. I have long had
to defend myself for not allowing my children to drink sodas for the
very reasons you mention.

œ~~Soda and other like beverages are said to be "bad" to your bones
because their phosphorus (phosphoric acid) limits the bones ability to
absorb calcium
I Need a Soda Please...
Also note that the soda that you love so much can hurt you in several ways:

* Provides sugar (food) to harmful bacteria and yeast causing acidity
in blood which leeches Ca/P out of bone, causing immune reactions in
gut that inflame gut wall, causing harmful gut material to leak into
blood, and causing the immune system to become more sensitive and
become more allergic.
·	Injects phosphoric acid into blood, which leeches Ca/P out of bone.

* The Phosphoric Acid in soda leeches metal out of dental amalgam,
especially copper Amalgam used in Finland, Norway, and Germany prior

Also note that one can hit a viscous (I™m sure the author meant
vicious cycle, and not a cycle that is thick!) in that their ATP
energy can become impaired (fatigue), they can reach for a soda to
give them a little boost and further hurt their health via the above
interactions, causing them to reach for another soda...

œSoft drinks that contain citric and phosphoric acid can decrease the
absorption of calcium. A 12-ounce cola may rob the body of 100
milligrams of calcium.

œPhosphorus is highest in protein-rich foods and cereal grains. In
addition, phosphorus additives are used in many soft drinks and
packaged foods. Phosphorus is not often present in supplements except
for certain calcium supplements, such as bone meal.

œPhosphorous deficiencies can be caused by excessive intake of
aluminum containing agents (such as certain antacids) because the
aluminum can bind to phosphorous. In addition, diabetes, starvation,
alcoholism, and conditions that can cause abnormal absorption of
nutrients (such as Crohn's disease, celiac disease, and radiation
damage) can lead to depletion of phosphorous in the body. Symptoms of
phosphate deficiency include loss of appetite, anxiety, bone pain,
bone fragility, stiffness in the joints, fatigue, irregular breathing,
irritability, numbness, weakness, and weight change. In children,
decreased growth and poor bone and tooth development may occur.

Having too much phosphorous in the body is actually more common and
more worrisome than having too little of this mineral. Excessive
phosphorous is generally caused by kidney disease or by consuming too
much dietary phosphorous relative to dietary calcium. As dietary
phosphorous increases, the need for additional calcium rises as well.
The delicate balance between calcium and phosphorous is necessary for
proper bone density and prevention of osteoporosis.

œI am confused -- is phosphorus good or bad (knowing that too much of
anything is almost always bad)?
 You are right. Calcium and phosphorous need to be in balance. In good
health, barring renal disease, an overdose of supplements or consuming
massive quantities of soda pop,our parathyroid gland and kidneys help
excrete excess calcium and phosphorous (PO4).

Phosphorous is the same as phosphate (different chemical form),
regarding the diet. œAlternate Names : HPO4-2, Inorganic Phosphate,
Phosphorus - Serum, PO4

œPhosphorus can be found in the environment most commonly as
phosphates. Phosphates are important substances in the human body,
because they are a part of DNA materials and they take part in energy
distribution. Phosphates can also be found commonly in plants.

œMost of the body's phosphorus is combined with calcium within the
skeleton, but about 15% exists in the blood and other soft tissues and
body fluids as phosphate (PO4) ions. Dietary phosphorus is efficiently
absorbed, so low PO4 caused by dietary deficiency is unlikely in the
absence of a malabsorption syndrome (inadequate absorption of
nutrients in the intestinal tract) for individuals on a normal diet.

PO4 levels are controlled by PTH, 1,25-dihydroxy Vitamin D and, to a
lesser extent, calcitonin. The 1,25-dihydroxy Vitamin D increases
absorption of calcium and phosphate in the intestines. PTH 1)
increases calcium and PO4 release from bone; 2) decreases loss of
calcium and increases loss of PO4 in the urine; and 3) increases
activation of 25-hydroxy Vitamin D to 1,25-dihydroxy Vitamin D in the

Absorption of calcium and phosphorus by the body is a complicated
pathway, involving also parathyroid hormones, kidneys, bowel, and
Vitamin D. The site below does a good job explaining the essence of
this cycle. (Only part of the article is posted here due to copyright
œPhosphorus is required by the body for bone and teeth formation.
Calcium alone can't build strong bones and tissues. New research shows
calcium needs phosphorus to maximize its bone-strengthening benefits,
and taking a lot of calcium supplements without enough phosphorus
could be a waste of money.

Phosphorus allows proper digestion of riboflavin and niacin, aids in
transmission of nerve impulses, helps your kidneys effectively
excreting wastes, gives you stable and plentiful energy, forms the
proteins that aid in reproduction, and may help block cancer.
Researchers say it's the first time the two elements have been shown
to be co-dependent for bone health. Both calcium and phosphorus are
found naturally in dairy products, but most calcium supplements and
calcium-fortified foods and beverages don't contain phosphorus.

More than half of all bone is made from phosphate, and small amounts
are also used in the body to maintain tissues and fluids. Taking large
amounts of calcium from supplements can interfere with phosphorus
absorption. Women trying to prevent or treat osteoporosis typically
take 1,000-1,500 mg of calcium a day in the form of supplements.
Researchers found this amount of calcium can bind up to 500 mg of
phosphorus, making it unavailable to the body.

Although this would present no serious problem for many people, it
could impact women over 60 years of age who have diets that contain
less than the National Academy of Sciences recommended daily allowance
of 700 mg of phosphorus.

œHow does calcium work? As with other minerals, the body has a
marvelous system for keeping the concentration of calcium in the blood
and tissues just right. This is needed because if calcium
concentrations fall too low or get too high, certain organs will fail
to function. The first checkpoint is in the intestines. If you eat too
much calcium or already have enough calcium in your blood, the
intestines simply absorb less of the calcium in the food you eat. If
your body needs calcium, the intestines absorb more. Bones are the
second checkpoint. If you don't get enough calcium in your diet, your
body may borrow what it needs from your bones. This works for a time,
yet continued withdrawals of calcium from the bone bank can lead to
osteoporosis. A hormone called parathyroid oversees all this calcium
activity like a vigilant bank manager, keeping the calcium
concentration just right. When calcium levels fall, this hormone
stimulates vitamin D to increase absorption of calcium from the
intestines and to release calcium from the bone bank until a proper
balance is restored.
œLabels on calcium supplements can be misleading. The figure that is
important is the amount of elemental calcium provided by the
supplement. This is the actual amount of useable calcium.

The rest of the calcium in the tablet is coupled with a salt that
makes it unavailable to the body. For example, calcium glutamate is
only 9 percent elemental calcium. A 500 milligram tablet of calcium
glutamate may contain only 45 milligrams of elemental calcium, even
though you may have been led to believe that you are taking 500
milligrams of calcium. Calcium carbonate, on the other hand, is 40
percent elemental calcium; 500 milligrams of calcium carbonate would
provide 200 milligrams of useable calcium. Labels on some supplements
make this distinction, listing both the type of calcium compound in
the supplement and the amount of elemental calcium provided. Other
products are not as carefully labeled. Read labels carefully and
compare several brands when you shop.

œPhosphorus deficiency is uncommon, because dietary intake is usually
adequate.3 Chronic alcoholics may become deficient in phosphorus.4 and
people taking large amounts of aluminum-containing antacids.

One study has shown that taking calcium can interfere with the
absorption of phosphorus, which, like calcium, is important for bone
health.6 . Although most western diets contain ample or even excessive
amounts of phosphorus, older people who supplement with large amounts
of calcium may be at risk of developing phosphorus deficiency. For
this reason, the authors of this study recommend that, for elderly
people, at least some of the supplemental calcium be taken in the form
of tricalcium phosphate or some other phosphorus-containing

œAs calcium intake increases without a corresponding increase in
phosphorus intake, phosphorus absorption falls and the risk of
phosphorus insufficiency rises. Intakes with high Ca:P ratios can
occur with use of supplements or food fortificants consisting of
non-phosphate calcium salts. Older patients with osteoporosis treated
with current generation bone active agents should receive at least
some of their calcium co-therapy in the form of a calcium phosphate

œPhosphorus is not usually considered a problem nutrient. If anything,
it has been argued, there is an excess of phosphorus in the food
supply, at least in the U.S. [11“14]. The facts, however, are not so
clearly supportive of this conclusion [15]. In comparison with
laboratory animals, in which the potential harm of high phosphorus
intakes has been mainly studied, human phosphorus intake is low.

œAbout 85 percent of phosphorus in the body is found in the bones and
teeth. The rest circulates freely in the bloodstream and operates
inside cells -- phosphorus is an important part of every tissue.
Phosphorous is widely distributed in foods, so a sufficient supply is
easily obtained in the diet. Milk, cheese, bakery products and meat
provide most of the phosphorus in our diets.

œCalcium is the most abundant mineral found in the body. Nearly 99
percent of the 2 to 3 pounds present in the body is concentrated in
bones and teeth. The remaining 1 percent circulates within the
The bones act like a savings account for calcium from which the body
makes a "withdrawal" when blood levels dip. The bones, however, pay
the price. During childhood and teen years, "deposits" of new bone are
added to the skeleton faster than old bone is removed. We reach peak
bone mass (maximum bone density and strength) around age 30. After age
35 or so, bone "withdrawals" begin to exceed "deposits" from the
savings account. This failure to maintain enough bone mass can
eventually result in osteoporosis, a crippling bone disease.

œCalcium recommendations were set at levels associated with maximum
retention of body calcium, since bones that are calcium rich are known
to be less susceptible to fractures. In addition to calcium
consumption, other factors that are thought to affect bone retention
of calcium and risk of osteoporosis include high rates of growth in
children during specific periods, hormonal status, exercise, genetics,
and other diet components.

Phosphorus, an important nutrient for bone and soft tissue growth, is
so prevalent in various foods that near starvation or a metabolic
disorder is required to produce deficiency. Different from former
RDAs, phosphorus values in the report are not derived in relation to
calcium. The values recommended are considered sufficient to support
normal bone growth and metabolism at various ages.

œWhat are calcium and phosphate?

Calcium and phosphate are two minerals which can be found in the blood
and tissues of the body.
They are the major components of bone, providing much of the essential
strength. In nature, calcium and phosphate can combine together to
form limestone.
The levels of calcium and phosphate in the blood are maintained in
careful balance. This balance is œsee-saw like in nature. As one
rises the other often falls due to hormonal and chemical factors. It
is important that these substances stay at normal levels in your blood
in order to maintain health.

What is the link between calcium phosphate balance and renal disease?

The kidneys are important in maintaining the balance of calcium and
phosphate in the blood. For people with kidney disease this balance
can be disrupted.

The kidney achieves this balancing act by filtering excess phosphate
from the blood and by producing a substance (active vitamin D) that is
essential in the absorption of calcium in the gut and the entry of
calcium into the bone. In
kidney failure these processes fail and phosphate accumulates in the blood.
As blood phosphate rises, calcium levels fall. This fall in calcium is
detected by the parathyroid gland, which initiates the release of
parathyroid hormone. Parathyroid hormone acts on bone to release
calcium back in to the blood.
The overall effect is that calcium levels in the blood are corrected
at the expense of calcium loss from the bone and a higher level of the
parathyroid hormone.

œMajor determinants of serum phosphorus concentration are dietary
intake and gastrointestinal absorption of phosphorus, urinary
excretion of phosphorus, and shifts between the intracellular and
spaces. Abnormalities in any of these steps can result either in
hypophosphatemia or hyperphosphatemia .
The kidney plays a major role in the regulation of phosphorus homeostasis.

œBone disease can develop when calcium and phosphorus are not balanced
and within good levels. When phosphorus is too high, the body takes
calcium out of the bones to bind with the phosphorus and remove it
from the blood. Bones become brittle as a result.
Dr. Heaney recommends that patients use a source with both calcium and
phosphorus, "such as dairy products and/or a calcium phosphate
The balance of calcium and phosphorus can especially impact women over
60 whose diets often contain less than the recommended dietary
allowance of 700 mg of phosphorus. Dr. Heaney states, "For these
women, the usual calcium supplement, calcium carbonate, may block most
of the absorption of phosphorus. If this happens, the calcium won't do
much good because bone mineral consists of both calcium and

œIs there a difference in the phosphorus found in a supplement like
Posture-D and that in soda?

  Posture“D contains phosphororus in the form of a phosphate,
tricalcium phosphate to be exact. Soda contains phosphate, and many
years ago, sodas were called œphosphates in some parts of the US.
œCoke and other soft drinks are acidified with phosphoric acid ( see
the list of ingredients on the side of the can/bottle ). When food
passes from the stomach to the small intestine, bicarbonate is added (
by the digestive apparatus ) to raise the pH. Under the acid
conditions of the stomach, the calcium in food is available, but when
the pH goes up in the small intestine, the calcium reacts with the
phosphate from the soda and precipitates. In that form, calcium
phosphate, it is not available for absorption.

This has nothing to do with the color of the soda. 
Drinking lots of soda on a daily basis is not a good idea for many
reasons. In addition to calcium interference, sodas provide empty
sugar calories - no vitamins, no minerals, no fat, no fiber, no salt.
A can or two once in a while is nothing to worry about, but if you're
drinking more than a can per day, you're cheating your body out of
nutrients it could get from less refined sources.
It is the contention of some food scientists that some major food
suppliers deliberately omit important nutrients from their products so
that the under-nourished body will eat more, seeking that which it has
not been given. As one man put the question: Who in the audience has
eaten just one Oreo? Yes, phosphoric acid in colas--and many other
sodas, is a binder to restrict the access of calcium to the body... I
drink a lot of colas, but now I take calcium supplements...

œPosture-D is a Unique Calcium Supplement
·	Formulated with Tricalcium Phosphate = As Easily Absorbed as Calcium from Milk*
·	Contains Phosphorus = Because Calcium Alone is Not Enough for Healthy Bones*
·	600 mg Calcium in Every Caplet = 120% Daily Calcium in Only 2 Caplets
·	Vitamin D = Helps your Body Absorb Calcium*
·	New Coated & Scored Caplet = Easier to Swallow

œWhat about phosphorus in an ordinary diet (for example, meat).
œDietary Sources 
Protein-rich foods, such as meat, poultry, fish, eggs, dairy products,
nuts, and legumes are particularly good sources of phosphorus. Other
sources include whole grains, hard potatoes, dried fruit, garlic
cloves, and carbonated beverages.

œBecause most foods contain sufficient amounts of phosphorus,
additional supplementation with this mineral is not generally
necessary. Sometimes athletes use phosphate supplements before
competitions or heavy workouts to help reduce muscle pain and fatigue.
Phosphorus and calcium can be used together to help heal bone
fractures and to treat bone disorders caused by vitamin D
deficiencies, namely osteomalacia and rickets (softening and weakening
of the bones in adults and children respectively).

Page 2

œCalcium-sensing proteins in the parathyroid glands sense serum
calcium levels. In response to slight declines in serum calcium, the
parathyroid glands secrete parathyroid hormone (PTH). PTH stimulates
the activity of the 1-hydroxylase enzyme in the kidney, resulting in
increased production of calcitriol, the biologically active form of
vitamin D. Calcitriol activates the vitamin D-dependent transport
system in the small intestine, increasing the absorption of dietary
calcium and phosphorus. Calcitriol and PTH act on the skeleton to
increase the mobilization of calcium and phosphorus into the
circulation. In the kidneys, calcitriol and PTH increase calcium
reabsorption and increase phosphorus excretion.

Hope this has answered your calcium-phosphorous balance questions!

If any part of my answer is unclear, please request an Answer
Clarification, before rating. This will allow me to assist your
further, if possible.

Regards, Crabcakes
Calcium phosphate balance
Dietary calcium + phosphate

Request for Answer Clarification by happytobeme-ga on 14 May 2005 11:02 PDT
Dear crabcakes:

Thank you for such a quick and thoughtful answer!  Just a few points
for clarification:

~What is the difference in the phosphoric acid in soda pop versus the
tricalcium phosphate in my Posture-D?  The first is "bad" while the
latter is "good"?

I'm concerned that taking a calcium supplement like Posture-D might
actually defeat my bone strenthening objective.  What are your

Thanks again!


p.s. I'm glad to know I am not the only mom who won't let her kids
drink soda.  I've gotten incredulous looks from other moms when I say

Clarification of Answer by crabcakes-ga on 14 May 2005 12:53 PDT
Hi again Happytobeme,

   Good clarification points! Without going into a long drawn out
chemistry lesson (Not my best subject!) the phosphate in soda is a
"form" of phosphorous. Some forms of PO4 may have a different ionic
charge, putting it in a different form. Some forms are more readily
absorbed by the body than others, by it's chemical configuration.
While not a truly accurate example, think of water. Frozen, it is a
solid form, boiled it goes into a gaseous form, and of course water as
we know it is liquid. Yet  all forms are water.

Each molecule of phosphorus needs a molecule of calcium to maintain
balance. As mentioned in the original answer, as long as one has
normal kidney function, and is in good health, homeostasis (the body's
system of balancing chemicals, hormones,water, minerals, etc) will
keep these minerals in balance. If one consumes excess phosphorus, the
molecules will seek  molecules of calcium, and if not found in tissue
or blood, will leech it from bones and teeth. That is the danger of
taking in too much phosphorus.

From the chart on this link, you'll see a normal diet includes plenty
of phosphorus, particularly eggs, meats and dairy products.

   As far as the supplement you mention, from everything I read, if
one eats a balanced diet, there is no need for extra phosphorus.

"An excess of phosphorus may lead to poor bone density, however.
Nutritionists point out that the body will attempt to maintain a
balance between ions of phosphorus and calcium in the blood. When an
excess of phosphorus (through phosphoric acid, for example) is
introduced, the body's chemical balance mechanisms will attempt to
maintain the proper calcium-phosphorus ionic ratio by extracting
calcium from the bones. The excess phosphorus and calcium are
eventually excreted. Other chemicals such as caffeine (also a
significant component of popular common cola drinks) are also suspect
as possible contributors to low bone density, which is now seen in
increasing prevalence in men of late middle age."

Regarding soda and kids: I feel a small amount of soda at a party is
acceptable, but soda pop provides nothing but empty calories. None of
the ingredients are GOOD for children, and almost all of them are bad
for children (and adults if taken in excess). Soda is acidic, due to
the phosphate, which destroys tooth enamel. The sugar causes cavities.
The phosphorus(phosphate form) leeches calcium from bones and teeth.
These are powerful reasons not to allow kids to consume soda. It
bothers me a great deal to see parents giving children, especially
small children, soda to drink. OK, I'm now stepping off my soapbox.

I hope this has helped clarify calcium-phosphorus balance to you!

Regards, Crabcakes
happytobeme-ga rated this answer:5 out of 5 stars
Excellent!  And a wonderful and polite clarification too!  Thank you very much!!

Comments   Log in to add a comment
Subject: Re: Phosphorus -- in Soda, Calcium Supplements and Diet
From: crabcakes-ga on 15 May 2005 12:47 PDT
Thank you for the five stars, Happytobeme!

Sincerely, Crabcakes

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