Find out how our home-cooked meals are killing us
and what we can do to save ourselves
We live at a time when we are bombarded with a million and one processed, junk and fast food temptations. No matter which way we turn our heads, there is a bag of chips, cookies, chocolate or soft drinks staring right at us. Trying to fill up your car’s gas tank? You have to confront your temptation at the point of payment. In a hospital for a reason? Most likely, your nearest food access is a vending machine filled with sugary, salty and oxidized oil junk.
The only place that we can keep ourselves safe from the exposure to all these junk food is at our homes. This is only true if we successfully resisted a million and one urges the junk food industry threw at us while we were outside.
Let’s say we are one of the strong-willed individuals, that by some help from the universe, do not carry junk and processed food or soft drinks at home and actually eat home-cooked meals made from scratch. Much better, right?
Well, it depends.
While home-cooked meals, made from scratch, are much more likely to be healthier than all those packaged or processed products, we may actually be adding lots of harmful molecules to our food through the preparation process. Let’s go through a few common molecules and see if you had them for your dinner tonight.
Lipid peroxides are produced when we fry food with oils high in polyunsaturated fatty acids. In the presence of heat, these oils react with oxygen in the air, giving birth to lipid peroxides. Lipid peroxides are oxidizing agents, able to oxidize our DNA, cell proteins, and lipids thereby causing a variety of chronic diseases or even death. In fact, lipid peroxides have been linked to cardiovascular diseases, inflammation, Alzheimer’s disease, neurodegenerative diseases, Parkinson disease, and cancer, as well as ocular (eye-related) and kidney degeneration.
Can you guess which oils give birth to most lipid peroxides in your food? Here are a few common ones: corn oil, sunflower oil, safflower oil, and soybean oil.
Canola oil doesn’t produce lipid peroxides as much as the above-mentioned oils, but it gives birth to another health monster, also contributing to the development of cancer.
On the other hand, virgin or extra virgin olive oil, coconut oil, and avocado oil are some of the most stable oils, producing the least amount of lipid peroxides when used in cooking with low temperature. (We will cover this topic in more details soon).
Cholesterol is an unstable molecule and when heated, it easily reacts with the oxygen in the air and is converted to cholesterol oxide. Animal studies have shown that feeding pure cholesterol to animals didn’t cause atherosclerosis (the blockages of arteries that lead to heart attack or stroke). On the other hand, feeding the animals cholesterol oxides was very blocking to the arteries, leading to cardiovascular diseases.
Where in your food may you be getting cholesterol oxides? Cholesterol is an animal molecule. This means that it is only found in animal products, such as dairy, cheese, meat, poultry, fish, and eggs. Every time we heat up one of these food types in the open air, we are essentially producing cholesterol oxides. On the other hand, submerging the animal product in water (as in soups, stews, or boiling) prevents the oxygen from reaching the food, thus minimizing the amount of cholesterol oxide produced. For instance, breaking the egg yolk (the part with all the cholesterol) to make scrambled eggs causes the formation of cholesterol oxides. Boiling the intact egg or poaching is the healthiest cooking method and the fried eggs are somewhere in between. Also, heated cheese, as in pizza or lasagna, is more likely to contain cholesterol oxides, compared to unheated cheese.
Cooking meat in water, as in stews, significantly reduces cholesterol oxide formation, while frying, grilling or broiling meat promotes cholesterol oxide formation.
Advanced glycation end products (AGEs):
Advanced glycation end products (AGEs for short) are molecules that are formed during the cooking process when the sugar in food reacts with a protein or a protein containing fat. AGEs are not broken down by the digestive enzymes. Instead, they are absorbed intact, enter our tissues and stay there for a long time.
Once inside our bodies, AGEs form toxic scar tissues in various organs and tissues. As our bodies try to breakdown these molecules, a large number of inflammatory molecules are released, leading to inflammation. Depending on the site of this toxic scar, different tissues, nerves, and organs may become damaged and we may experience a variety of symptoms.
Some of the AGE-related diseases include cardiovascular diseases, complications of diabetes, cataract, memory loss, fibromyalgia, skin aging and wrinkles, rheumatic arthritis, peripheral neuropathy, as well as other inflammatory illnesses. In fact, many of the diseases that we may attribute to aging could be as a result of this specific inflammatory process.
The factors that contribute to the amount of AGEs formation are the cooking temperature and the water content. Food that is cooked with low heat and moist produces a much lower amount of AGEs compared to food that is cooked with high heat and without moist. For instance, 100 grams of boiled potatoes contain 17 units of AGEs while the same 100 grams of potatoes made into homemade French fries contain 694 units of AGEs. Processed foods and ready to eat cereals are also very high in AGEs as they have been processed with very high temperatures. The duration of cooking doesn’t affect the amount of the AGEs produced.
Also, AGEs have been shown to increase an inflammatory molecule in the blood, called C Reactive protein (CRP). The presence of C reactive protein in blood is an indicator of systemic inflammation. It is also a risk factor for many diseases such as heart disease and rheumatic arthritis. Switching from cooking methods that create a significant amount of AGEs to other safer methods contributes to significant reduction of CRP molecule in the blood. Stewing, steaming, and boiling methods can reduce the AGE content of food by about 50% compared to grilling, broiling, or frying.
Mutagens and carcinogens:
Cooking meat with high heat or in direct contact with flames causes various cancer-causing compounds (known as mutagens and carcinogens). Consuming heavily cooked meat such well done, browned, fried, grilled, and charbroiled increases the risk of different types of cancer including breast cancer, lung cancer, as well as prostate and colon cancers. The carcinogens and mutagens are formed when meat becomes in the direct contact with fire or is being cooked in high temperature as in frying and grilling. Adding oil to the meat (as done during frying or grilling) significantly increases the production of these cancer-causing compounds. Also, the charred (or burnt) portions of grilled meat, fish or poultry contain a carcinogen, called heterocyclic amines (HCA). HCA molecules enter our cells and cut our DNAs. The DNA cut causes a genetic disruption that can lead to cancer. In contrast, baked or boiled meat has ten to fifty times less content of mutagens and carcinogens.
What is the solution?
You may now be thinking that you are better off if you stop eating altogether; or even worse, you should stop caring since no matter what you do, you will be at the risk of all these harmful molecules.
The good news is that there is a way to eat healthily. First, with correct healthy cooking guidelines, we can significantly reduce our exposure to harmful molecules in our food. Second, our bodies have the ability to eliminate harmful molecules. We can optimize our health by supporting our bodies’ detoxification processes. (We will cover this topic in more details soon).
In summary, different cooking methods have distinct effects on our food composition and ultimately on our health. It’s always wise to practice healthier cooking methods to optimize our health.
May food be our medicine and not our poison!
Dr. Rasa Nikanjam, BSc, ND, A Holistic Healing Practitioner
Did you learn anything new? Quiz yourself with our Healthy Cooking Self-Assessment Quiz to find out.
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