The toxin in question -- 4-hydroxy-trans-2-nonenal (HNE) -- collects in high amounts in polyunsaturated oils that have linoleic acid, which include canola, corn, soybean and sunflower. However, HNE doesn't form in saturated oils coming from animal fat.
Although you may not have heard of it before, HNE has quite toxic as a health threat documented in studies two decades old, according to the lead researcher.
Some of the diseases associated with exposure to HNE:
- Cardiovascular disease
- Huntington's disease
- Liver ailments
Liquid oils are at risk for oxidative damage when heated - high polyunsaturated oils and even highly monounsaturated oils like olive oil.
Knowing the risk means you can do something about reducing your own risk.
- Avoid eating foods fried in restaurants since oil is heated, heat is maintained at a high temperature and then the oil is often re-heated for use again until it degrades beyond use.
- For foods that are sauteed, ask what the oil used is and be sure the chef is sauteeing at a low-to-moderate temperature.
- Avoid packaged foods that are fried in suseptible oils - potato chips, corn dogs, etc.
- When you choose liquid oils to purchase in the supermarket, choose ones that have not been "heat processed" or "refined" - choose cold pressed oils only.
- At home, use liquid oils only once and then discard. Do not heat the oil to an extremely high temperature and do not use if it's been kept at a high temperature longer than 30-minutes.
- At home, use highly stable oils for cooking - cocunut oil is one of the best "high heat" oils to use and comes packed with nutrients and antimicrobial properties.