The late Dr Michael Mosley once praised a diet that may help prevent dementia - and it's something many of us may want to look into. Studies also suggest it could delay the progression of Alzheimer's disease by nearly four years.

The much-loved expert, who popularised the Fast 800 diet, praised the Mediterranean diet's benefits. The Fast 800 website explains: "Research shows that a moderately low carbohydrate, Mediterranean-style diet has the unique power to restore your body's ability to reach its ideal weight and stay there, as well as reduce your risk of chronic disease."

It adds: "The Mediterranean-style diet succeeds where other diets fail because it's not just about eating less of the wrong foods - it's about eating more of the right foods. These foods keep you feeling full, offer important nutrients and taste delicious."

A Mediterranean diet includes lots of fruits, vegetables, and whole grains, with moderate amounts of oily fish and dairy. It has low amounts of meat, sugar, and saturated fat. Most of the fat comes from olive oil, and alcohol is consumed in moderation, usually with meals.

The Alzheimer's Society says that following this diet does not mean you have to eat traditional Mediterranean food. It is more about the overall eating pattern.

The Alzheimer experts note the diet could "protect against some of the damage to brain cells associated with Alzheimer's disease."

It 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 because 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."

It also said that studies focused on dementia have shown mixed results. However, one large study found that following a Mediterranean diet could reduce the risk of dementia by up to 23%.

It suggests trying the following:

• Include wholegrain starchy foods in most meals - for example, wholemeal bread, rice and pasta.
• Eat more fruits, vegetables, pulses (for example, beans, peas and lentils) and nuts and seeds.
• Eat less red meat - for example beef and lamb, and especially processed meats such as sausages and bacon.
• Eat fish regularly - particularly oily types like salmon and mackerel. However, try to limit your intake of battered or breaded fish, which is high in unhealthy fats.
• Try to choose lower-fat dairy foods where possible.
• Use vegetable and plant oils for cooking and dressing, such as olive oil and rapeseed oil. Try to avoid solid fats like butter, lard or ghee.
• Limit the amount of salt in your diet - try not to eat more than 6g (about a teaspoon) a day.
• Try to make sugary foods only occasional treats - such as pastries, sweets, biscuits, cakes and chocolate.
• Consume alcohol in moderation (ideally with food) - if you don't drink alcohol already, try not to start.

A studyfound that this diet may slow brain changes linked to early Alzheimer's disease. The results suggest that changing your lifestyle could help lower the risk of this type of dementia. It explained: "The brain scans taken at the beginning showed that the people who ate a Western diet already had more beta-amyloid deposits than those who ate a Mediterranean diet. Beta-amyloid is a protein known to collect in the brains of people with Alzheimer's disease.

"The brains of those who ate a Western diet also showed lower energy use - a sign of brain activity - at the beginning of the study than those who ate a Mediterranean diet. Both these differences suggest the early development of dementia."

It concluded: "The researchers estimate that there may be as much as a three-and-a-half-year delay in progression of Alzheimer's disease in people who have eaten a Mediterranean diet for many years, rather than a standard Western diet.

"Research that involves larger and more diverse groups of people over longer periods of time is needed to confirm these findings. More work is also needed to understand exactly how a Mediterranean diet may protect people from harmful brain changes."

Stuck for ideas? Check out a 7-day meal plan inspired by the Mediterranean diet online via the BBC's Good Food website here.