Cooking on High Heat Could Increase Your Heart Disease Risk


The level of heat in your kitchen may have a direct correlation to your chances of developing a dangerous heart condition, says a new study appearing in the journal Nutrition.

Researchers found that cooking foods at a high temperature, commonly done when frying or roasting, forms dangerous byproducts that can increase your risk of coronary heart disease (CHD), a narrowing of the arteries that can lead to heart attack or death.

Flickr Image Courtesy: Ricardo Liberato, CC BY-SA 2.0
Flickr Image Courtesy: Ricardo Liberato, CC BY-SA 2.0

The byproducts, called neo-formed contaminants (NFCs), include heart-harming substances like trans-fatty acids that are linked to a wide range of conditions, including high cholesterol, heart disease, stroke and diabetes.

The researchers found that NFCs proliferate when foods are cooked at high temperatures, and specifically when foods are cooked in oil at elevated temperatures. The harmful results are made worse when oil is used more than once.

Identifying a dietary cause for heart disease could have tremendous public health benefits, note the researchers. CHD is the leading cause of death among both men and women in the U.S.

A Closer Look at the Study

A research team led by Raj Bhopal, a professor of Population Health Sciences at the University of Edinburgh in Scotland, sought to understand why certain populations are more susceptible to heart disease than others. They noted that South Asian populations in India, Pakistan, Bangladesh and Sri Lanka have higher rates of CHD than others.

“Known risk factors do not fully explain the high prevalence of coronary heart disease (CHD) among South Asians,” note the researchers.

Looking beyond other risk factors, such as genetics or age, the researchers focused on dietary habits and created a compelling argument that specific methods of cooking have a direct impact on heart health.

Related: Red Meat Doesn’t Harm Your Heart as Much as You Think

“South Asians’ cuisine is dominated by frying and roasting techniques that use high temperatures,” explain the researchers. That makes trans fats highly prevalent in their daily diet. Bhopal offers an example of how different cooking methods lead to highly divergent levels of harmful byproducts: Boiling a chicken releases about 1,000 NFCs, while frying a chicken unleashes more than 9,000, or about 900 percent more.

Simply put, “high-heat cooking, common in South Asian cuisine, leads to an increased production of neo-formed contaminants including advanced glycation-end products and trans-fatty acids,” state the researchers.

The researchers compared commonly consumed foods in South Asia with foods eaten in China, which are often boiled, braised or steamed. Overall, they found significantly lower rates of CHD among the Chinese population than the other Asian countries they studied.

Related: Eating Nuts Every Day Might Lower Your Heart Disease Risk

CHD has a number of risk factors, and most of them – cholesterol and obesity, for example – are tied to the effects of diet. Lifestyle changes are known to decrease the risk of developing CHD, and the new research pinpoints a specific risk factor to avoid.

The researchers surmise that the elevated incidence of CHD among South Asians is at least “partly attributable to high-heat treated foods,” and they encourage further study on the topic.

“It is exciting because if our findings are proven to be correct, we could make a real impact on rates of heart disease within a generation,” they add.