High- Versus Low-calcium Water for Bone Health

Calcium is essential for bone health, and the primary source for most people is dairy products. But what about calcium in drinking water? Some natural mineral waters contain significant amounts of calcium, and this study investigates whether drinking high-calcium water (compared to low-calcium water) over a period of time improves markers of bone health — offering a simple, accessible way to support bone density without supplements or dietary changes. The study is open to adults aged 25–55 with a BMI between 18 and 30. Participants must be willing to maintain their usual diet and exercise habits throughout the study. Exclusions include: currently drinking water already high in calcium (>150 mg/L), pregnancy, breastfeeding, menopause, heart/vascular/kidney/cancer disease, neuropsychiatric conditions, GI diseases or surgeries, and taking medications that affect bone or fluid balance (like corticosteroids or diuretics). Participants drink assigned water (high or low calcium) for the study period and have bone markers measured in blood and urine. This research is important because bone loss is a major public health concern — especially for aging populations — and simple, affordable dietary interventions like mineral water could complement existing prevention strategies.