A new study from Edith Cowan University in Australia and the Danish Cancer Research Institute has found that not all sources of nitrate in food are the same when it comes to brain health.
The researchers discovered that eating nitrates from vegetables may help lower the risk of dementia, while getting nitrates and nitrites from meat and drinking water may increase the risk.
Dementia is a complex illness that can be caused by many things, including genetics, aging, and lifestyle. In this study, scientists followed more than 54,000 adults in Denmark for up to 27 years. They looked at how much nitrate and nitrite people got from their food and water, and where it came from—whether from vegetables, meat, or drinking water.
Their findings were clear: people who ate more vegetables high in nitrate had a lower chance of developing dementia. But those who got more nitrate and nitrite from animal-based foods like red meat, processed meat, and even drinking water had a higher risk of dementia. The difference seems to come down to what else is in the food.
When we eat vegetables rich in nitrate—like spinach, lettuce, and beetroot—our body turns that nitrate into a helpful compound called nitric oxide. Nitric oxide can improve blood flow and protect the brain. Vegetables also contain antioxidants and vitamins, which help the body use nitrate in a healthy way and stop it from forming harmful substances.
But the story is different with meat and processed foods. These foods do not have the antioxidants found in vegetables. Instead, they often contain compounds like heme iron, which may actually cause the body to turn nitrates into N-nitrosamines. These substances are harmful and have been linked to cancer and possibly brain damage.
This study is also the first to link nitrate in drinking water to a higher risk of dementia. The researchers found that people who drank water with nitrate levels well below the safety limit used in Europe still had a slightly higher risk.
For example, water with just 5 milligrams of nitrate per liter was linked to more dementia cases, even though the legal limit is 50 milligrams per liter.
However, the researchers say it’s important not to panic. Drinking water is still much better than sugary drinks like soda. The increase in risk is small for individuals. But the results suggest that health officials should take a fresh look at the safety limits for nitrates in water and do more research into long-term effects.
It’s important to remember that this was an observational study. That means it shows a link between diet and dementia risk, but it doesn’t prove that nitrate causes dementia. Other lifestyle factors or parts of the diet may also play a role.
Still, the study offers a simple message for everyday life: eating more vegetables and cutting back on red and processed meat may help protect your brain. Just one cup of baby spinach a day could make a difference.
These findings support what many experts have already said: a diet full of vegetables and low in processed meats is good for your health—not just for your heart, but possibly for your brain as well.
If you care about brain health ,please read studies about Vitamin B9 deficiency linked to higher dementia risk, and cranberries could help boost memory.
For more health information, please see recent studies about heartburn drugs that could increase risk of dementia, and results showing this MIND diet may protect your cognitive function, prevent dementia.
The study is published in Alzheimer’s & Dementia.
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