Medicine has been getting it wrong for more than 40 years: saturated fats from foods such as dairy and red meat don’t cause heart disease, they help prevent it, a leading heart specialist has said.

The real culprits are the trans fats found in processed and fast foods, bakery products and margarines, says Aseem Malhotra, cardiology specialist at Croydon University Hospital in London.

And although we’re told to cut down on the trans fats, we’re advised to do the same with saturated fats, and yet recent studies have shown these have a protective effect. The fats in dairy produce lower blood pressure and protect against diabetes, a precursor of heart disease. Red meat has a similar protective effect, but it’s the processed meats that cause the damage, possibly because they contain preservatives such as nitrates and sodium.

The 40-year mantra of lowering total cholesterol levels through reducing the amount of fat we consume has paradoxically increased our risk of cardiovascular disease, and put millions of people on powerful statins that they don’t need.

(Source: British Medical Journal, 2013; 347: f6340).