Eating porridge/Oats for just two days could slash bad cholesterol for six weeks and boost heart health

Eating nothing but porridge for just two days may significantly reduce “bad” cholesterol and offer lasting heart protection, according to new research that’s turning conventional diet advice on its head.

Oats have long been associated with improved cholesterol levels, but scientists from the University of Bonn say the benefits may appear far sooner than previously believed. Their study found that people at high risk of heart disease experienced a 10 per cent drop in LDL cholesterol after following a short, calorie-restricted diet made up almost entirely of oats for just two days.

LDL cholesterol is considered particularly dangerous because high levels are linked to heart attacks and strokes. The cholesterol-lowering effect is thought to come from beta-glucan, a soluble fibre found in oats. Once consumed, beta-glucan forms a gel-like substance in the gut that binds to cholesterol and reduces the amount absorbed into the bloodstream.

Until now, health experts believed adults needed to consume about three grams of beta-glucan daily—roughly a bowl of porridge every day—to achieve a five to 10 per cent reduction in cholesterol over time. However, the new findings suggest that a short, high-intensity “oat reset” may deliver comparable results in just a few days, especially for people with metabolic syndrome. This condition includes a combination of obesity, high blood pressure, and elevated blood sugar, all of which increase the risk of diabetes, heart disease, and stroke.

Notably, the cholesterol improvements remained stable six weeks after participants returned to their normal eating habits.

The study, published in the journal Nature, involved 32 participants who followed the short-term oat diet. During the two-day intervention, they ate only porridge, split into three meals of 100 grams each. Small amounts of fruit or vegetables were allowed, but total calorie intake was limited to about half of what participants normally consumed.

A control group was also placed on a calorie-restricted diet but was free to eat whatever foods they preferred. While both groups saw some health benefits, the improvements were far greater among those who consumed only oats.

According to study co-author Professor Marie-Christine Simon, LDL cholesterol levels in the oat group dropped by 10 per cent—a change she described as substantial. Participants also lost an average of two kilograms and saw a slight reduction in blood pressure.

Further analysis revealed that the oat-based diet boosted beneficial gut bacteria. These bacteria produce compounds such as ferulic acid, which may help lower cholesterol by suppressing an enzyme involved in cholesterol production in the liver.

Interestingly, a longer six-week version of the study produced different results. In that phase, participants replaced just one daily meal with porridge made from 80 grams of oats. This approach did not lead to significant cholesterol reductions, suggesting that short-term, high-dose oat consumption may be more effective than gradual changes.

The researchers concluded that oat-based diets—particularly brief, intensive interventions—offer meaningful metabolic benefits. They noted that this strategy could be a fast, well-tolerated way to manage cholesterol levels and reduce the risk of diabetes, while also opening new possibilities for gut-focused nutritional therapies.

Cardiovascular disease remains the leading cause of death worldwide, accounting for around 30 per cent of global deaths and long-term disability. In the UK alone, more than half of adults are believed to have high cholesterol.

While statins are widely prescribed and effective for many, they are not suitable for everyone, and a significant number of patients fail to reach healthy cholesterol levels even after years of treatment. These findings highlight the growing importance of practical, diet-based solutions that can support long-term heart health