Cooking in extensively reheated oil pose serious health threats

Rawalpindi

The use of again and again reheated oil to fry ‘iftar’ dishes like ‘pakoras’, ‘samosas’, ‘kachoris’ and ‘jalebis’ etc. can be a risk factor for heart disease, breast cancer and prostate along with a number of other serious health threats though majority of population is unaware of the fact.

Studies conducted in the past have shown that repeatedly reheated oil even of the finest quality transforms into Trans fatty acid that is one of the main risk factors behind heart diseases and stroke.

The consumption of dishes in again and again reheated oil may expose one to high levels of toxic aldehydes, chemicals known to cause neurodegenerative disease and cancer.

A study conducted some 12 years back found that a toxin called 4-hydroxy-trans-2-nonenal (HNE) forms when such oils as canola, corn, soybean and sunflower oils are reheated. Consumption of foods containing HNE was found to be associated with increased risks of cardiovascular disease, stroke, Parkinson’s disease, Alzheimer’s disease, Huntington's disease, various liver disorders and cancer.

Studies also reveal that once absorbed in the body, the HNE reacts with DNA, RNA and proteins affecting basic cellular processes.

Health experts believe that there is a need to create awareness among public that ‘iftar’ dishes should not be fried in again and again reheated oil to avoid heart diseases that claim over 17.5 million lives every year around the globe and more than two third of these deaths occur in developing countries.

To avoid risk factors caused by Trans fats, people should not use ‘iftar’ dishes prepared at commercial level and should discard oil at home after using it two to three times for frying or it should be stored properly in refrigerator after straining, said Medical Specialist Dr. Muhammad Sohail Tariq while talking to ‘The News’.

It is important that Trans fat raises Low Density Lipoproteins (LDL) termed as bad cholesterol and lowers your High Density Lipoproteins (HDL), the good cholesterol. A high LDL cholesterol level in combination with a low HDL cholesterol level increases risk of heart disease.

Studies reveal that people who consume high amounts of trans fats have twice the heart-attack risk and stroke risk than those who consume little. Also women with the highest blood levels of trans fats have twice the risk of breast cancer as compared to the women with low levels. Trans fats also increase the risk of prostate cancer in men.

One can easily witness shopkeepers, bakers, confectioners and vendors selling ‘iftar’ dishes prepared in again and again reheated oil mainly because the concerned government authorities have not been taking action against them.

Dr. Sohail said that at commercial level, the ‘iftar’ dishes are fried in low quality edible oil whose trans fats are highly injurious to health and these should be avoided.

Some of aldehydes generated through reheating of oil dissipate after being produced in cooked oil though many others linger and accumulate and upon consumption, these toxins then reacts with human proteins, enzymes, and hormones, which can lead to serious health problems, said Intensive Care Unit Medical Specialist at Pakistan Institute of Medical Sciences Dr. Muhammad Haroon while talking to ‘The News’.

He added that for safety and quality, use fresh cooking oil each time you fry however, if you deep-fry significant amounts of food frequently as is being done in Ramazan, it is not always practical from an economic standpoint. In such case, one should choose oils with a high smoke point and prepare food for minimal contamination of the oil, he said.

He added that after use, oil should be strained to get out any food particles left over and after proper storage, most oils can be reused.

On storage of used oil, experts say that as soon as oil cools enough to handle, strain through layers of cheesecloth, paper towels or coffee filters to remove food particles and store it in a clean glass jar.

Never mix it with unused oil. Seal the jar tightly and refrigerate or freeze for no longer than a month. It may become cloudy in the refrigerator or freezer, but will clear at room temperature. Never reuse oil if it foamed or changed colour during heating or if it has an odd odour or smells like the food you cooked.