Toxic Culprits Found In Vegetable Oils
Is vegetable oil really the healthier choice? Currently the South African Food Based Dietary Guidelines among other countries in the world, still support the use of vegetable oils, but according to recent research these cooking oils may be doing us more harm than good.
These dietary guidelines advise us to, “Use fat sparingly; choose vegetable oils rather than hard fats. Rather use good (unsaturated) fats like vegetable oils and soft tub margarine in small amounts.” But could these hydrogenated oils be doing us more harm than saturated facts like butter or coconut oil?
Cooking Up A Toxic Storm
Vegetable oils as we know them are processed forms of soya, sunflower, canola, corn or palm oil. According to the latest scientific trials, cooking with these oils releases a high concentration of aldehydes: rather toxic chemicals, which have been linked to diseases such as cancer, heart disease and dementia.
In January 2005, The Journal of Agricultural and Food Chemistry published the Spanish study on heated sunflower oil. They found “The formation of some well-known genotoxic and cytotoxic oxygenated aldehydes in this process.” They clearly found aldehydes present in the gas released from the cooking oil. In 2008 the same journal published a further study on sunflower oil showing the aldehydes are easily absorbed through the digestive tract and could circulate through the body.
Earlier this year experts at De Montfort University Leicester (DMU) carried out research to determine the levels of toxic chemicals released from various cooking oils. Volunteers were given sunflower oil, vegetable oil, corn oil, cold-pressed rapeseed oil, olive oil, butter, goose fat or lard to use in cooking their daily meals. The used oil was collected and sent to DMU’s labs to be analyzed.
Professor Grootveld and his team found sunflower oil and corn oil produced levels of aldehydes 20 times higher than that recommended by the World Health Organization. Olive oil and butter were found to produce far fewer aldehydes, but coconut oil produced the lowest levels of these harmful chemicals. Butter and coconut oil are richer in monounsaturated and saturated fats, which are much more stable when heated and therefore are a healthy choice, but consumers must consider the high levels of saturated fats in respect of their overall dietary requirements.
Trans Fats In Cooking Oil
Cooking oils and margarine all contain an artificial fat known as a trans fat. Most trans fat is formed through an industrial process known as hydrogenation, where hydrogen is added to vegetable oil. In the case of vegetable oil, it is partially hydrogenated which gives it a longer shelf life. For margarine it is hydrogenated until it becomes solid at room temperature.
In 2013 the New York Times wrote a report on the nutritional scientist Fred Kummerow and his research on trans fats. In 1957, a young Kummerow stepped into Illinois University and requested to investigate the arteries of people that had died from heart attacks. As one would presume the arterial walls were lined with fat, but to his surprise Kummerow found that it was not saturated fat, it was trans fat. His life’s work was laid out in that moment; he became one of the first pioneers to show the link between heart disease and processed foods, a link that is still not acknowledged by most nutritional guidelines.
In the past decade, Kummerow has published four papers in peer-reviewed scientific journals. He has shown how an excess of polyunsaturated vegetable oils like soybean, corn and sunflower are responsible for atherosclerosis, or the hardening of the arteries. Since trans fats create oxidative stress and inhibit the action healthy fats such as omega-3 are also under investigation for their impact on neurological disorders.
The Downside Of Omega-6
Vegetable oils contain high levels of omega-6. Many scientists believe that the high volume of omega-6 can essentially bump the important omega-3 molecules out of the receptors in the brain. This is thought to be a contributing factor to the increase in mental health issues.
The Cancer Association of South Africa’s (CANSA) published a paper on healthy agriculture and nutrition in 2010. The author Dr Carl Albrecht, the head of the Research Cancer association of South Africa, shared his insights on the subject of Omega-6 and Omega-3 gleaned from the Inaugural Conference of the World Council on Genetics, Nutrition and Fitness for Health held in Greece in October 2010.
Dr. Albrecht writes that optimal nutrition involves an optimal ration of approximately 2:1 omega-6 to omega-3 fatty acids. At the conference Artemis Simopoulus, President of The Center for Genetics, Nutrition and Health, Washington D.C said, “Human beings evolved on a diet that had a ratio of omega-6/omega-3 of about 1/1, whereas Western diets have a ratio of 10/1 to 20-25/1. This higher ratio is associated with a higher risk for coronary heart disease, colorectal cancer, asthma, osteoporosis, arthritis, neurodegenerative diseases, and various aspects of mental illness, violent behavior and deficient cognition in both children and the elderly.” A balanced ratio of omega-6/omega-3 was found to reduce the risk for inflammatory disorders, cancer, atherosclerosis, diabetes and neurodegenerative disease.
The Good Fats From Plant Oil
All cold pressed plant oils, like extra virgin olive oil have health benefits, but when it comes to cooking it seems the two natural oils that contain saturated fat are the best for cooking. Saturated fats are needed for healthy cell membranes in our organs, muscles and in our brain.
Olive oil is considered to be one of the most healthiest options to add to food and sasy Melissa Kelly, registered dietitian. it can be used for cooking at a moderate temperature, not higher than 180°C. Extra virgin olive oil has a lower smoking point of 163°C. Avocado oil should not be used for cooking as it has the highest smoking point of 256°C and linseed oil is very fragile and not be heated.
Organic butter on the other hand has the ideal balance of a 2:1 ratio of omega-6 to omega-3. It is also a good source of short and medium-chain fatty acids, as well as your fat soluble vitamins A, D, E and K. Butter from grass fed cows contains a Conjugated Linoleic Acid (CLA) a compound that can help provide protection against different types of cancer, and helps the body build muscle instead of fat. The cholesterol in butter is the good type that can also be used by the body for cellular function.
Coconut oil steps out of this equation completely; it doesn’t contain any omegas but it is an amazing source of medium-chain triglycerides (MCT). This rare form of fat is highly beneficial; it is quickly and easily digested, it helps to support the immune system and metabolism as well as providing the brain and body with a great source of energy. MCT is unique in the way that it goes directly to the liver to support metabolic processes and it doesn’t need enzymes for absorption. It can help one to lose weight, improve brain function and it is a strong natural anti-inflammatory. Coconut oil is also a good source of fuel for the steroid hormone system, helping to support stress, fertility and good thyroid function. However it is important to note, that coconut oil is made up of 75% fatty acids and could potentially be LDL raising, so moderation is advised.