It's long been known that just over-heating, let alone burning, some foods can lead to the formation of compounds linked to cancer. These include heterocyclic amines and so-called polycyclic aromatic hydrocarbons (PAHs), which can lead to fried or smoked foods posing a health risk.
A articles says: "Acrolein is highly toxic and may be formed from carbohydrates, vegetable oils, animal fats and amino acids during heating of food. In the present study, we investigated adults' intake level of cooked meat using high temperature cooking method such as pan frying or grilling directly over an open flame and indirect fire using pan. The 925 adults (438 men and 487 women) participated in this nationwide survey. According to the result of frequency intake of cooked meat at high temperature, the most frequently consumed cooked meat at high temperature was fried chicken, followed by indirect cooking-samgeybsal and directly grilled fish and mackerel pike among twenty five kinds of cooked meats and foods, which were eaten more than three times per month. The woman consumed direct grilled fish and mackerel pike more than three times per month, while the man consumed samgeybsal, pork cutlet, and fried chicken once per week. The order of total intake amount of cooked meat per adult for a year is 10.3 kg of fried chicken (man 13.1 kg, woman 8.04 kg), 6.7 kg of samgeybsal (man 9.4 kg, woman 4.7 kg) and 5.1 kg of jeyukbockeum (man 7.0 kg, woman 3.6 kg). The results of present study suggest that adult must realize the risk of consuming cooked meat at high temperature and the need for education for proper dietary habit to prevent geriatric diseases."
Fried foods such as potato chips, French fries, expanded snacks, roasted nuts,
extruded noodles, doughnuts and fried fish and chicken have gained worldwide popularity. Heat generated food toxicants such as acrylamide.
Acrylamide is a white odorless crystalline solid, soluble in water, ethanol, ether, and chloroform. Formerly, acrylamide was known only as a constituent of cigarette smoke and products of plastics and water treatment chemicals. In early 2002, acrylamide was detected in a range of foods heated during production or preparation. It is one of the chemicals known as Maillard reaction products, which formed when foods are heated at high temperatures. Particularly high concentrations were found in products of plant origin heated to high temperatures, such as potato chips, French fries, pan- fried potato products, or crisp bread, whereas the contents in foods rich in protein were low.
Diet and nutrition play a key role in the promotion and maintenance of good health, as they are important modifiable risk factors for chronic diseases. World Health Organization recommends limiting the consumption of saturated and trans-fats (hydrogenated fats), sugars and salt in the diet, which are often found in snacks, processed foods and drinks.
Evidence suggests that regular and excessive consumption of energy-dense
foods high in fat, particularly saturated fat, and in refined carbohydrates can lead to weight gain, obesity and pose an increased risk for non-communicable diseases.