Fried food tastes good, but it’s not very healthy for you. A new metastudy reports that consumption of such food is linked to an increased risk of major heart disease and stroke.

Most of us today make an effort to not eat only fast food and take-out, which is admirable, but that doesn’t make our diets ‘healthy’ per se. Western dietary habits are known to promote poor cardiovascular health, the authors note, but it was still unknown how much fried food specifically contributed to this. In order to get a better idea of the effect such food has on our cardiovascular health, a team of Chinese researchers has reviewed past research on this subject.

Don’t fry

The team reviewed 17 studies involving 62,445 participants and 36,727 major cardiovascular events (such as a heart attack or stroke). They also pooled in data from a further 6 which tracked their patients over a long timeframe (9.5 years on average), involving 54,873 participants and 85,906 deaths. Put together, the data was meant to help us gauge how damaging fried food is to our cardiovascular health, and how much they increase our risk of death from cardiovascular disease.

The results show that participants in the group who consumed the most fried food had a 28% higher chance of experiencing a cardiovascular (CVS) event than those who consumed the least. They also had a 22% higher risk of coronary heart disease and a 37% higher risk of heart failure.

Even when the team controlled for various factors and participant characteristics, the link between the consumption of fried food and major cardiovascular events, coronary heart disease, and heart failure remained. The risk increased with each additional 114 g weekly serving by 3%, 2%, and 12%, respectively, the authors report.

Still, the findings aren’t necessarily conclusive. Some of the studies only tracked one type of fried food, for example fried fish or potatoes, not participants’ total intake. Furthermore, every study was designed differently and all relied on information the participants were asked to remember (which is unreliable). The team explains that all these elements could mean the studies “underestimated” the association between these and cardiovascular health. They also note that such factors need to be taken into account when interpreting the results.

Exactly how fried foods can influence the development of cardiovascular disease is still unclear, but the team has some possible explanations. First off, fatty foods are very energy-dense but the vegetable oil they contain gets broken down into trans fatty acids inside our bodies, which is harmful. Frying also generates a host of byproducts involved in inflammatory processes, and fried food is often very salty (an excess of salt is also bad for you).

The paper “Fried-food consumption and risk of cardiovascular disease and all-cause mortality: a meta-analysis of observational studies” has been published in the journal BMJ.