New research from two universities says where nitrate comes from matters for brain health.
What the Study Looked At
Scientists followed more than 54,000 Danish adults for up to 27 years. They measured how much nitrate and nitrite people ate from different foods and drinks, then checked who developed dementia.
Veggie Nitrate Helps the Brain
People who ate more nitrate from vegetables, like a cup of baby spinach each day, had a smaller chance of getting dementia.
Experts think the benefit comes from the mix of vitamins, antioxidants, and nitrate in veggies. These nutrients help the body turn nitrate into nitric oxide, a good molecule, while stopping the creation of harmful chemicals called N‑nitrosamines.
Meat does not have those protective nutrients. In fact, iron in red meat may even boost the formation of N‑nitrosamines, which could hurt brain cells.
Meat and Water Nitrate May Raise Risk
Higher intake of nitrate from animal foods—especially red and processed meat—was linked to a higher dementia risk.
Even low levels of nitrate in drinking water (as low as 5 mg per litre) were associated with more dementia cases, despite being far below the EU safety limit of 50 mg/L.
Water lacks the antioxidants that vegetables provide, so nitrate from water might more easily turn into the bad N‑nitrosamines inside the body.
What This Means for You
The study does not prove that nitrate causes dementia; it only shows a connection. Still, eating more vegetables and cutting back on red and processed meat fits with many other health guidelines.
There is no need to stop drinking water. The extra risk from low‑level nitrate is tiny, and water is still far healthier than sugary drinks.
Next Steps
Researchers say more lab work and long‑term trials are needed to understand exactly how nitrate from different sources affects the brain.
In the meantime, choosing a plant‑rich diet and drinking clean water remain smart choices for protecting brain health.