A leading health guru has revealed that spending just 10 minutes on one simple kitchen trick before cooking could dramatically cut cholesterol levels and slash your risk of heart disease. Professor Tim Spector, who is one of the founders of the ZOE diet app who became a household name during the Covid pandemic, has shared his game-changing advice for anyone using chopped onion and garlic in their cooking.

The expert insists that letting these ingredients sit for 10 minutes before they hit the heat can supercharge levels of a powerful chemicalthat tackles cholesterol head-on. Speaking to The i, Prof Spector explained how this straightforward technique also helps keep blood sugar levels steady.

The professor's guidance forms part of his top dietary tips, where he highlighted: "Onion and garlic, as well as cabbage and broccoli, are good sources of sulforaphane, a chemical that has been shown to improve glucose control and cholesterol levels."

He explained that the cooking process wipes out an enzyme called mirosinase, which is crucial for producing sulforaphane. But by giving vegetables a five to 10-minute breather before cooking, the sulforaphane gets "activated" and survives the heat treatment.

Prof Spector also dished out another clever meal-planning strategy, revealing: "There is emerging evidence that eating salads or other vegetables as starters ten minutes or so before you have a carbohydrate-rich meal can help to keep you fuller for longer and reduce blood sugar spikes from the starchy food."

The diet expert also recommended Brits incorporate more fermented foods into their diets, such as kimchi. He praised vinegar for its role in salad dressings, explaining that its acidity helps stabilise blood sugar levels, keeping you feeling satisfied between meals and reducing the temptation to snack.

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Other tips included swapping processed stock cubes for miso paste and cooking tomatoes in extra-virgin olive oil to extract more nutrients. Prof Spector shared his personal preference: "I drizzle and spread extra virgin olive oil on my toast rather than butter, for greater health benefits. This is what they do in Spain, and it tastes delicious."

He suggested a healthier breakfast alternative: "Instead of quickly reaching for cereal, have full-fat Greek yoghurt topped with nuts, seeds, and berries. It contains less sugar, and the toppings will help you reach your 30 plants a week. Research shows people who eat 30 different plants a week tend to have a more diverse gut microbiome than those who eat 10. A flourishing microbiome can help the body fight infections, reduce the risk of autoimmune disease, and regulate appetite and body weight.

"Eating the rainbow not only supports your gut health and reduces the risk of disease, it also enriches your diet with a greater range of flavours and textures (and will help you reach your 30 plants a week target too). A simple and cheap way is to buy pre-mixed combinations; packs of multi-coloured peppers are a good example, as are combinations of other root vegetables, or mixed nuts and seeds."