Craving to have a croissant or a pastry? It might not be a good idea, as daily consumption of these delicious foods can cause severe damages to your heart, according to a team of researchers from the University of Oxford in UK who found serious health risks involved with a diet high in saturated fat.

The study, presented at the European Society of Cardiology Congress 2024 in London, found that eating cakes, biscuits or pastries daily increased one's risk of having a heart disease in a very short period. However, eating a diet high in polyunsaturated fat like walnuts, oily fish (salmon, mackerel), sunflower oil protected the heart.

For the study, 24 people were placed on a diet high in either saturated or polyunsaturated fat for 24 days.  Participants underwent an MRI scan and blood test before and after the study.

At the end of the study, researchers noticed that though participants did not gain weight after following the 24-day diet high in saturated fat, they had a 10 percent higher levels of bad cholesterol in their blood and a 20 percent rise in fat in their liver than before they started the diet.

These changes in cholesterol and fat can place them at higher risk of developing type 2 diabetes and cardiovascular diseases, they said.

"We want to study how the type of fat that a person eats affects their risk of heart and circulatory disease beyond a change in body weight. The results suggest that a diet high in saturated fat may negatively change cardiovascular disease risk factors even when a person does not gain weight," lead researcher Nikola Srnic from the University of Oxford, said in a statement.

On the other hand, the team noticed that the group following a diet high in polyunsaturated fat had a 10 percent drop in their total blood cholesterol levels and bad cholesterol levels and also an increase in energy reserves in their heart muscle than before starting the diet.

"We saw protective effects if a person ate a diet high in polyunsaturated fat. Although our study is ongoing, findings so far suggest that even when you are not gaining weight, different fats can have drastically different effects on our health in a short time frame," Srnic explained.

To reconfirm their findings, the researchers grew heart muscle cells in environments enriched with saturated or polyunsaturated fats and found that the cells grown in environments with more polyunsaturated fat were more capable of taking up fat and breaking it down for energy than the latter.

Researchers said that their experiment clearly explain how a diet high in polyunsaturated fats helps lower levels of fats in blood.

"Saturated fat has long been understood to cause a much higher risk of heart and circulatory disease. This study adds to this consensus and gives us evidence that saturated fat may silently start to pose a risk to heart health very quickly, without causing any changes to a person's weight," Professor James Leiper, Associate Medical Director at British Heart Foundation, said. 

The findings come at a time when around 17.9 million people across the world are killed by cardiovascular diseases or diseases of the heart and blood vessels.