Neurologists reveal three popular foods that are ‘worst for brain health’ and could cause dementia in the future

By admin 21.12.2025 3 min read

Neurologists have revealed the three foods that are ‘worst for brain health’ and could be linked to dementia.

While there is conflicting research and evidence over how our diets are linked to developing dementia, it’s widely accepted that following a Mediterranean diet gives you a good chance of ensuring a healthy lifestyle, which can, in turn, benefit brain function.

Alzheimer’s Society explains: “For most people, following the Mediterranean diet is a good way to ensure a healthy diet, which may be important for maintaining good brain function.

“One of the reasons that the Mediterranean diet is thought to be beneficial is that it is high in antioxidants from fruits and vegetables. These may help to protect against some of the damage to brain cells associated with Alzheimer’s disease. Research has suggested that this may be beneficial to help maintain memory and thinking skills.”

They went on to explain that a recent study suggests that sticking to a Mediterranean diet could reduce dementia risk by up to 23 per cent.

Aside from following a diet rich in oily fish, wholegrains and fruit and vegetables, some other foods should be avoided, according to experts.

Fizzy drinks

Neurologist Dr Shaheen Lakhan told HuffPost that due to the high sugar content in fizzy drinks, soda can be one of the worst foods.

“Soda is one of the worst foods for brain health due to the high concentration of simple sugars, which damage the blood vessels supplying the brain,” he said.

“Over time, this starves the brain from the very fuels it needs to function, leading to premature dementia and strokes. Acutely, sugar also causes brain inflammation, irritability, poor mood and sleep disturbances.”

Margarine

Many people assume that real butter is the worst option for your health, and while butter is high in fats, margarine contains trans fats, which raise ‘bad’ cholesterol.

“We often hear that trans fats aren’t good for your heart and blood vessels. The same applies to the vessels of the brain,” said Dr Shae Datta.

“A study from the journal Neurology found that older adults who had the highest levels of elaidic acid (a common type of trans fat) in their blood were more likely to develop dementia. Better to stick to olive oil and real butter.”

French fries

Everyone enjoys French fries as a treat, but Dr Pedram Navab has explained that foods high in fat can cause damage to blood vessels.

“A diet that incorporates fatty foods like French fries can damage blood vessels that supply the brain, causing cognitive impairment,” he said.

“It reduces the blood-brain barrier (BBB) integrity and leads to neuronal damage of the hippocampus, a part of the brain that is instrumental for learning and memory.”