Some Health Dangers of Cooking Food at High Temperatures
Dr Hector Perera London
Most people are unaware of the adverse effects of high temperature cooking. We cannot blame our good old “kussi amma” because they were totally unaware of those matters but now the present generation with more modern cooking facilities must be aware of the good and bad side of high temperature cooking. Clay pots are bad conductors of that means it takes time to heat anything in them. I think the slow heating of the food inside a clay pot is really good because the food itself are bad conductors of heat. Once the food get heat lots of chemical changes takes place quite slowly, some juice ooze out while some get in. I am sure those clay pots cook the food but as I said it takes time to get them heated up. In the meantime most of the heat put to the cook get radiated or get waste but that is a different issue. Have you noticed that food cooked in clay pots taste better than those cooked in metal cooking pots? One of the reason is that the ingredients get absorbed better when cooking in clay pots as there is not enough heat for them to get evaporated quickly with the cooking aroma. The gas and electric temperature must be controlled so that the ingredients do not disappear into the air without getting absorbed into the food.
Now a days we are very worried about energy wastage in cooking but we do not think that food are slow conductors or heat or bad conductors of heat. Have you ever thought about what happens when you cook food? Certainly there must be chemical changes within the food due to heat provided by the fire. All food have very complicated chemicals so they will undergo changes due to heat.
What Happens When We Cook Food at High Temperatures
30% to 50% of the vitamins and minerals are destroyed. One of the things that can effect is the vitamins on the food. We know certain food have certain vitamins but they will be no longer there once heat is applied because they get damaged. We lose up to 97% of the water-soluble vitamins (Vitamins B & C) and up to 40% of the lipid-soluble vitamins (Vitamins A, D, E & K). Some protein becomes coagulated, making it less digestible (studies suggest that cooked proteins are up to 50% less likely to be utilized by the body.) We know which food have proteins and which have vitamins. Any kind of meat and eggs have proteins but they would not be the same once cooked, even with low temperature. Certainly we cannot eat them raw just like cats and dogs, they must be cooked. The point is high temperature definitely damage these proteins.
Over-cooked food might take on a different meaning than it has previously. Not only is acrylamide formed in some starchy food but also meat cooked at high temperatures has as many as 20 compounds known as heterocyclic amines, or HCAs for short. HCAs are known as cancer causing chemicals.
The higher the temperature that food is cooked, the longer it stays in the gut and the more difficult it becomes for our digestive mechanisms to digest it. This makes it more difficult for the food to absorb and function at a cellular level where it needs to work. When the food cannot function in the cells, the cells can become deficient and/or toxic which leads to deficiency and toxicity of the whole body making the body less able to function optimally.
There are many ways to cook food, some with less harmful results. Steaming, boiling, and stewing expose food to heat not exceeding 100 degrees C. On the other hand, baking and roasting expose food to temperatures up to 200 degrees.
Microwaving also exposes food up to 200 degrees C. but there are also many other problems with microwaving food. The highest temperatures that foods are exposed to are broiling and barbecuing which can be 400 degrees C. Frying with a pan or wok normally uses high surface temperatures.2
As early as 1930 research was done in Switzerland showing what processed and cooked food did to the leukocytes, the white blood cells in humans. Prior to this research it was noted that upon eating there would be an immediate increase of the white blood cells which was called “digestive leukocytosis.” Digestive leukocytosis means that there is a rise in the number of white blood cells after eating. At the time this was considered a normal physiological response to eating. It was not know why the cells would increase after eating and this increase usually meant that the person had been exposed to a harmful substance such as toxic chemicals, a trauma or infection.
Then at the Institute of Clinical Chemistry, Dr. Paul Kouchakoff found that eating unaltered, raw food or food heated at low temperatures did not cause a reaction in the blood. Kouchakoff also found that if the food was processed or heated beyond a certain temperature it caused a rise in the number of white blood cells. He found that foods that had been refined, homogenized, pasteurized, or preserved causes the greatest increase in white blood cells.
No more “Kussi Ammas”
I do not think that we should go back to cooking in clay pots due to many reasons but I think what we did in the past have some meaning. If we wanted to get similar results we must control the amount of heat put to cook food than wasting energy then eating food that are quite tasty. In my scientific method I have controlled the energy put to cook the food so that there is a minimum wastage of energy. In addition there are many advantages of low fire cooking. Today the people are in a hurry, no time to waste so they cook at high temperature and damage the food or they rush to eating junk unhealthy, salty and oily food. Any way it is up to them but try not to waste energy in cooking unless they want to walk up and down like “Tandoori Chickens”. It is true those cooking aroma get deposited on the body and on the clothes then most Sri Lankan ladies just cover up by spraying some scents and colognes or they employ someone like “Kussi amma” to cook the food. Now most of them have found employment abroad and there are no more “Kussi Ammas”, they are gold dust. Your comments are welcomed perera6@hotmail.co.uk
