Calcium is one of the most important micronutrients used by the body. It is crucial for bone and tooth health, but also plays important roles in muscle contraction, nervous system function, and vascular system function. Calcium is also used as a co-factor in hundreds of enzyme reactions, and is an essential part of cell-to-cell communication.
The importance of calcium in so many of the body’s main functions means that having an adequate store of calcium on hand is essential. Bones, which are made primarily of calcium and potassium, serve as the perfect storage facility for calcium.
Bones are continually undergoing a process of remodeling, which occurs as calcium and potassium salts are absorbed by the bloodstream or deposited in bones. Calcium is absorbed into the bloodstream when blood calcium levels fall too low. Similarly, if levels of calcium in the blood are too high, calcium is re-deposited for storage in bones.
This mechanism is the reason why insufficient dietary calcium can cause osteoporosis: when dietary calcium intake is low, calcium is continually drawn from bones. This leads to a deficit of this mineral in the bones, the result of which is that bones become more brittle.
Calcium and Ligament Health
This explains why calcium is so important for bone health - but what about calcium and ligament health - is there a connection?
Ligaments are made up of fibrous connective tissue that does not contain any calcium. Proper joint function requires that ligaments be flexible and somewhat stretchy, which means that calcium deposits on ligaments would prevent them functioning properly. So, calcium is not important for good ligament health.
In fact, bony calcium deposits on or near ligaments, tendons, or any other type of soft tissue can actually be harmful and prevent healthy joint or tissue function. Calcium deposits can develop in a process known as calcinosis or calcification, in response to certain types of stimuli.
Dystrophic calcification occurs in response to soft tissue or ligament damage. This is a response to inflammation caused by tissue damage, and involves the deposition of calcium into damaged tissues as part of the healing response. This is an abnormal reaction that is more likely to occur when blood levels of calcium are too high.
Metastatic Calcification is most often the result of a system imbalance in calcium levels, typically caused by chronically high levels of free calcium in the blood, or by kidney failure. This type of calcification can cause the development of calcium deposits in multiple locations in the body, including in tendons, ligaments, and other soft tissues.
National Institute of Health Office of Dietary Supplements: Dietary Supplement Fact Sheet: Calcium
Oregon State University Linus Pauling Institute: Micronutrient Information Center: Calcium
University of Washington Department Of Radiology: Musculoskeletal Radiology: Soft Tissue Calcifications