10.16:
Essential Minerals for Bone Health
Bone tissue requires minerals such as calcium, phosphorus, magnesium, fluoride, and manganese, for its overall health and structural integrity.
Calcium ions, and phosphorus in the form of inorganic phosphate, combine to form hydroxyapatite crystals, which are the major component of the mineralized bone matrix.
However, other ions, such as magnesium and fluoride, are also incorporated into these crystals.
In fact, fluoride ions can replace hydroxyl ions in hydroxyapatite crystals to form more stable and less acid–soluble fluorapatite crystals.
Additionally, magnesium and fluoride ions can also control bone cell functions by regulating specific enzyme and hormonal activities.
Similarly, manganese ions also act as a cofactor to several enzymes, including those involved in synthesizing glycosaminoglycans. These glycosaminoglycans are a part of the proteoglycans, which along with collagen fibers, constitute the organic bone matrix.
Due to their intricate role in the formation and maintenance of bone tissue, excess or deficiency of minerals in the body can lead to severe ailments. For example, excessive accumulation of fluoride in the bones causes skeletal fluorosis.
10.16:
Essential Minerals for Bone Health
The minerals contained in all of the food we consume are essential for our organ systems. However, certain essential minerals, such as calcium, phosphorus, magnesium, manganese, and fluoride, largely affect bone health.
Calcium and Phosphorus
Calcium is a critical component of bones, especially in the form of calcium phosphate and calcium carbonate. Since the body cannot make calcium, it must be obtained from the diet. However, calcium cannot be absorbed from the small intestine without vitamin D. Therefore, intake of vitamin D is also critical to bone health.
Calcium and phosphorus together form hydroxyapatite crystals, which provide stiffness to the bone. Calcium and phosphorus in the bones are also essential to maintain mineral homeostasis in the body.
Magnesium
Magnesium influences the activities of osteoblast and osteoclasts cells. Magnesium also affects the concentrations of both parathyroid hormone and the active form of vitamin D, which are significant regulators of bone homeostasis. Magnesium deficiency might be a risk factor for osteoporosis.
Fluoride
Fluoride can displace the hydroxyl group in the hydroxyapatite crystals to form fluorapatite crystals. Similar to its effect on dental enamel, fluorapatite also helps stabilize and strengthen bone matrix. Fluoride can also enter spaces within hydroxyapatite crystals, increasing their density. However, excessive accumulation of fluoride in the bones can lead to a disorder known as skeletal fluorosis, which is characterized by weak and brittle bones.
Manganese
Manganese is required to synthesize mucopolysaccharides, also called glycosaminoglycans, one of the major components of the organic bone matrix. It also acts as a cofactor for several enzymes in the bone tissue.
This text is partially adapted from Openstax, Anatomy and Physiology 2e, Section 6.6: Exercise, Nutrition, Hormones, and Bone Tissue.