Cholesterol is one of those health issues that can quietly build up over time. You might feel perfectly fine, but behind the scenes, rising levels can increase your risk of serious heart problems, making it all the more important to keep an eye on what you eat.

The good news? Improving your cholesterol doesn’t have to mean expensive supplements or complicated meal plans. In fact, research suggests that a simple, budget-friendly breakfast staple could make a real difference.

According to scientists at the University of Bonn, oats – a cupboard essential that can cost as little as 85p from Aldi – may play a powerful role in lowering cholesterol.

Naturally rich in fibre and protein, and classified as a complex carbohydrate, oats have long been praised for their health benefits. A small trial found that eating a diet largely based on oatmeal for just two days led to a “significant” improvement in cholesterol levels, highlighting just how effective this everyday food could be.

The trial study found that consuming a diet consisting almost exclusively of oatmeal for just two days could improve cholesterol levels "significantly".

Whilst it was a small-scale study involving just 68 participants, scientists found a "substantial reduction" in levels of harmful LDL low-density lipoprotein (LDL) cholesterol among those who followed the oat-exclusive diet.

The diet consisted of 300g of oatmeal cooked in just water for all three meals a day, and participants were only allowed to eat some fruit or vegetables with their dishes.

Commenting on the results, Marie-Christine Simon, junior professor at the Institute of Nutritional and Food Science at the University of Bonn, said: "The level of particularly harmful LDL cholesterol fell by 10% for them – that is a substantial reduction, although not entirely comparable to the effect of modern medications.

"They also lost two kilos in weight on average, and their blood pressure fell slightly."

LDL cholesterol becomes deposited in the walls of blood vessels if there is too much of it in a person's blood, and these deposits are known as plaque.

The plaque narrows blood vessels, leading to higher blood pressure. The risk of deposits rupturing and forming blood clots that can block the blood vessels is also high, and can lead to deadly cardiovascular problems.

Oatmeal helps reduce cholesterol by increasing the number of certain bacteria in the gut, said Linda Kluempen, lead author of the trial. The bacteria produces phenolic compounds, including something called ferulic acid, which "has a positive effect on the cholesterol metabolism", she explained.

The study also found that eating an oat-based diet short-term, but regularly, was more effective than eating a smaller volume of oats over a longer period of time.

The positive effects of the two-day oats diet was still evident even after six weeks. However, the study showed that participants who consumed 80 grams of oats per day over six weeks saw only a small benefit in comparison.

"A short-term oat-based diet at regular intervals could be a well-tolerated way to keep the cholesterol level within the normal range and prevent diabetes," Simon said.

"As a next step, it can now be clarified whether an intensive oat-based diet repeated every six weeks actually has a permanently preventative effect."

Wholegrains, including barley and quinoa

Olive oil

Oily fish, such as salmon and mackerel

Beans, like chickpeas and kidney beans

Pulses, like lentils

Citrus fruits

Nuts

Soybeans and tofu

Apples

Aubergines