Dementia Risk Linked to Tap Water Nitrates

Nitrates, found naturally in vegetables and added to processed meats and tap water, have been linked to an increased risk of dementia, according to a new study. Researchers investigated nearly 55,000 Danish adults over a 27-year period. The findings indicate that people whose diets were rich in plant-based nitrates, such as those found in spinach or beetroot, had a lower risk of developing dementia.

Conversely, individuals consuming higher amounts of nitrates from processed foods and tap water showed a greater risk. Scientists suggest that antioxidants present in vegetables help convert nitrates into beneficial nitric oxide, while blocking the formation of harmful N-nitrosamines. Animal-based foods lack these antioxidants, and compounds like heme iron in meat might promote N-nitrosamine formation.

This research is the first to connect nitrates in drinking water to elevated dementia risks. While current EU and UK regulations set the limit for nitrates in drinking water at 50 mg/L, the study observed increased risk at levels as low as 5 mg/L. Researchers emphasize that this does not mean people should stop drinking water, but suggest regulatory bodies re-examine existing limits and further investigate long-term, low-level exposure effects on brain health. Increased vegetable consumption and reduced intake of red and processed meats are recommended.