By Dr. Robert Heaney
Protein, particularly of animal origin, is caught up in political correctness. Some argue, in fact, that we consume too much protein and that, for example, we would not have such a high calcium requirement if only we would eat less meat.
It has been known for nearly 80 years that increasing protein intake increases urinary calcium loss.
Because urinary calcium loss is the most important physiologic determinant of calcium retention, excess protein intake should be bad for bone, other things being equal. Some studies have indeed found this, but others found exactly the opposite.
Interestingly studies show that with increased protein intakes, rather than being harmful to bone, those with osteoporosis substantially improve recovery after hip fracture and reduce age-related bone loss in the other hip.
A positive effect of protein on bone is not surprising, as bone tissue is nearly 50% protein. However, a large fraction of the amino acids in bone collagen cannot be reused in new protein building. New bone turnover thus requires continuous intake of new protein.
If we don't eat enough protein, bone rebuilding is low on the body's priority list. But the other 50% of bone is mineral, and here calcium plays the crucial role. Without a diet containing sufficient calcium and protein, new bone formation will be limited.
There appears to be a homeostatic normalization that occurs which explains the paradox of the increased calcium lost in the urine with extra protein resulting in increased bone mass.
The homeostatic feedback system controlling the calcium balance does not regulate calcium intake and has no mechanism for assessing it. The system simply uses the combined calcium input from the kidney, gut and bone to prevent or offset a decrease in serum ionized calcium resulting from an increased calcium leak from the body.
In this way, increased protein intake which causes increased calcium loss in the urine, would be predicted to affect bone negatively, mainly at low calcium intakes.
Thus, it appears that protein and calcium act synergistically on bone if both are present in sufficient quantities in the diet. However, protein may seem to be detrimental to bone density because of its ability to cause one to excrete calcium in the urine when one's calcium intake is low.
American Journal Clinical Nutrition April 2002;75(4):609-10
DR. MERCOLA'S COMMENT:
One of the arguments vegetarians are found of stating is that increased protein intake, especially animal protein, results in loss of calcium from the bone.
As Dr. Heaney explains this is not entirely true. If one has inadequate protein intake it is clearly quite detrimental to bone density. There are many studies that clearly demonstrate this.
However, if one has excess protein intake and does not adequately have sufficient calcium in the diet, the protein will cause loss of calcium from the bones into the urine to buffer the system.
Having large amounts of raw vegetables which are high in calcium and other acidic buffering agents will clearly compensate for this.
Additionally, sufficient quantities of vitamin D in the summer from sun and in the winter from cod liver oil will also maximize calcium absorption to more than compensate for the loss of calcium from protein intake in most people.
| The Links Below Jump To Pages On Whatever Web You Are In | |||
| Table Of Contents | Search This Web | Navigation Help Page | |
| Write To Karl Loren -- He Pledges To Answer EVERY Personal Message, Personally. Click here or on his name in the box below. | |||
| The Links Below Are To Various Web Sites Published By Karl Loren | |||
| Karl Loren Web | Vibrant Life Web | Karl Loren's Book | |
| Super Colostrum | Bulk MSM | Heart Disease | |
| Emmessar | Happiness | Arthritis | |
| Instead Of | Chelation Therapy | Super Colostrum (2) | |
| Karl Loren's Catalog Store | Central Page For All 12 Webs! | ||
|
I promise to answer your message -- click here to send me a personal message
|
SUBSCRIBE: The Wednesday Letter is a free electronic monthly newsletter written and published by Karl Loren. You can view more than 50 back issues of this publication by clicking here. The Wednesday Letter subscription list is maintained on a secure server, no name is ever given or sold to anyone, and it is never used except for this Newsletter. It is automatically published on the Tuesday night just before the first Wednesday of every month. You can subscribe to this free monthly electronic letter by entering your eMail address and name below. You will then automatically receive a request for confirmation, sent to whatever address you have entered. If you do NOT receive this confirmation request, then you will not be subscribed. There may have been an error with your address and you should resubmit. The letter is never sent twice to the same address -- so you do not have to worry about a duplicate subscription. When you receive this confirmation request you must reply to it, or your subscription will not become active. No one can subscribe your name, and address, without you being notified, and if you get an unwanted notice of subscription you only need to DO NOTHING and the subscription will NOT be active.
REMOVAL: You can remove yourself from the subscription list in several different ways. Click here to read about this entire newsletter system. Every edition of The Wednesday Letter is delivered to your address with YOUR name and address in view on the letter, with a link that allows you to remove THAT name from the subscription list. If you try to send this removal message from an address different from the one you used to send in your original confirmation, then you will get a warning notice first, sent to the subscription address, asking you to confirm that you want to be removed from the list -- by replying to THAT request for confirmation, you will then be automatically removed. Thus, no one else can unsubscribe you, from some other computer, without your knowledge. But, if you send in the unsubscribe notice from the same machine used to receive the Letter, then the removal from the subscription list is automatic.
Personal Message: When you send a personal message to Karl Loren, you will receive a personal reply as per his instructions. Karl pledges that every personal message will get a personal answer. When you provide your mail address, we will send you free information including our free catalog and a cassette tape lecture by Karl Loren about heart disease, no charge, by mail, even if outside the US. You can select particular information you would like to receive, along with the free cassette tape and catalog.
