Why would thicker bones create disadvantages for the body?

In the context of evolutionary biology and medicine, the human body maintains a balance between bone strength and other physiological needs. While thicker bones might seem advantageous for structural support, they can create significant disadvantages:

• Brittleness and Structural Integrity: Increased bone density does not always equate to improved health. For example, excessive intake of fluoride can lead to denser but irregularly structured and brittle bone, which is more prone to fracture rather than being stronger.1
• Metabolic Costs and Mineral Homeostasis: Bone serves as a critical reservoir for calcium, which must be kept within narrow limits in the blood and soft tissues to support vital functions like muscle contractility, blood clotting, and cardiac function. If bones become excessively dense or mineralized through abnormal processes, it may disrupt the body's ability to mobilize these essential minerals when dietary intake is insufficient.1
• Pathological Abnormalities: Conditions such as marble bone disease (osteopetrosis) demonstrate that abnormal bone thickening can lead to deformities and skeletal abnormalities. Furthermore, the accumulation of minerals in soft tissues—such as in hydroxyapatite deposition disease—can cause pain, swelling, and limited range of motion, highlighting the risks of dysregulated mineralization.23