T Nation

Animal Protein and Bones?

You will often read (and I think it has actually been proven) that animal protein can leech calcium and/or other minerals out of bones, causing bone weakness. Whether or not it causes bone weakness in bodybuilders who are performing weight-bearing exercise in addition to eating probably several times over the recommended daily intake of calcium, I don’t know. So I don’t know if us lot who do this, but also eat a lot of animal protein should be worried…?

Also, I’m not sure if it’s just animal protein that causes the bone loss, or too much of ANY protein, including vegetable protein. If it is the first case, does anyone know what’s so special about animal protein that only it and not veggie protein causes the bone loss?

Has anyone actually experienced bone loss from eating too much protein whilst exercising and having a good diet, taking in a lot of calcium?

Is anyone here on a vegetarian bodybuilding diet eating lots of pea + brown rice combo protein (which is apparently a complete protein, but would probably be the worst tasting thing on earth) because they’re worried about it?

Is anyone here on a low-protein bodybuilding diet because of this? Could a low-protein bodybuilding diet even work?

Thanks in advance for your responses people.

I think it’s any protein… nothing is good for you in excess. I think meat eaters consume over the recomended amount of protein. As a vegetarian, i’m usually spot on the 70g a day recomended and i eat mostly carbs!

Lentil dahl and rice is nice :stuck_out_tongue: I’m not a bodybuilder tho!

I think the bone loss is only a problem later on in life, causing osteoporosis. You wouldn’t notice it while young.

Thats my thoughts…

I think vegetable sources of protein are lower in leucine than animal sources and leucine is the most responsible amino acid in signalling protein synthesis.

Heavy lifting is good for bone density, protein is good for the rebuilding of damaged tissue. I would think as long as you are lifting some extra protein in a reasonable amount can only benefit you.

False alarm, eat your meat in peace. :slight_smile:

quick google explains more

But like paulieserafini said heavy lifting is good for bone density.

Broscience part: I remember reading that when the bone gets atleast 10% of its tolerable force it will become stronger. Also, you dont see Jay Cutler’s etc having problems with bone density right?

I also remember reading those who consume vegetarian protein seem to have lower bone density, dont have the source for that one either, and I am going to sleep now. Correct me if I am wrong :slight_smile:

Calcium is pulled from the bones IF NECESSARY to reduce acidity caused as a by-product of protein metabolism. Eating greens, or anything more alkali or containing calcium or other alkali substances keeps the body in check. Eat meat AND vegetables you’ll be fine. OR eat animal protein AND BONES and you’ll be even better (plenty of calcium in the articular parts), which is what I thought this post would be about anyway, eating bones.

Bone metabolism is positively influenced by animal protein intake, vitamin D, calcium, magnesium, potassium, and phosphorus (though very few diets are deficient and in typical intakes it can act negatively if the preceding are low since it is “acidic” to the kidneys). Any studies showing negative effects ignore that fact that protein typically accounts for at best 15% of the subjects’ diets.

It is rather the lack of vegetable intake, and high amounts of refined carbohydrate and fat (over half of calories - white flour alone is around 20% of North American caloric intake, sugars are above 15%, and high omega 6 refined oils are around 18%). If one was to remove say 80% of these three categories and double other food intake, animal protein would be high, but so would veggies, fruits, and more micronutrient dense carbohydrate sources.

Magnesium and potassium intake are the two largest factors in the general population and also in most training individuals. Magnesium tends to be around 25% shy of required intake and potassium is only slightly above half of requirements. Removing some of the refined grains, sugars, and fats (over half of caloric intake for the general population) and replacement with quality animal protein (read raw meat you cook yourself), veggies - particularly green leafy and cruciferous, tubers, and healthy food fat sources such as nuts and seeds will put you at or above required intake levels.

In addition to what TrPAssassin said about calcium leaching, glutamine is also leached from muscles in such cases. It seems to be a general catabolic response.

Vegetable protein lacks essential amino acids, and the food combining techniques to mitigate this lead to high relative carbohydrate intake making it impossible to achieve 1g/lb protein on a maintenance or slightly above diet.

@ NikH:

I will leave our beef for the other thread, though Mr. Cutler likely uses some anabolic compounds which are know to promote bone density. He purportedly also eats lots of beef.

scroll about halfway down. Yep, past the chick with the icecream, I know…

The claim of protein allegedly leaching calcium from the bones comes from bad science where not all else was held constant.

Specifically, the calcium/phosphorus ratio was allowed to fall far lower in the animals losing calcium.

Then protein was blamed.

Aside from the fact that this is not seen when the Ca/P ratio remains constant, obviously in practice any number of people consume a great deal of protein and do not lose calcium from their bones on an ongoing basis, else they would not have the bone mass that they obviously do.

For that matter, look how many teenagers consume a great deal of protein (or otherwise have “acid-forming diets”) and, obviously, add to their bone mass rapidly, thus disproving theories that such diets cause loss of bone mass.