WARNING! DOUGHNUTS MAKE YOU OLDER

CHEMICALLY ALTERED trans fats found in many processed foods are bad news — particularly for the brain. They raise levels of cholesterol and other blood fats and promote inflammation in the body, increasing the risk of stroke, cognitive decline and dementia.

You need only a small amount of trans fat in the diet to develop cognitive impairment. Studies suggest people who eat 2g a day have twice the risk of declining memory and thinking skills than those who eat less. Beware doughnuts, biscuits, crackers, muffins, pies, cakes, creams, spreads and sweets full of trans fats. Ready-meals and frozen pizza are also on the brain blacklist.

To preserve memory (and lower the risk of diabetes), we also need to limit our sugar intake to just the amount and type the brain needs. High blood-sugar levels cause metabolic problems such as inflammation and insulin resistance (a precursor to type 2 diabetes where the cells stop responding to the hormone insulin), which in turn raise our risk of dementia.

Avoid anything that breaks down quickly into sugar and has little fibre — fizzy drinks, fruit juice and white-flour foods such as pasta and pizza. Instead, get sugar from complex carbohydrates such as sweet potatoes and fruit such as berries, as they provide a slower, more steady release of energy, while keeping blood-sugar levels stable.