Food preparation is a wondrous thing, it will often increase the food value in nutrition and taste. Poorer cooking methods may also decrease the health value of food in our diets. Many of the changes are easily visible to the human eye, like as meat cooks we see the colour and texture of it change, vegetables become softer and the tone of colour may change.
Whole foods, natural compounds and antioxidants may become not just less nutritious, but actually bad for you during the certain cooking processes. Carcinogens, or mutagens are what we call these unhealthy substances. The chemical changes to foods include the amino acids (proteins), creatines, and carbohydrates (any sugars included). Higher cooking temperatures are most likely to bring about these changes, before the total breakdown to plain carbon (charcoal).
There are some specific compounds to know about, that we cannot find written on a label but can look out for and prevent with alternative cooking methods:
Heterocyclic amines (HCA) and polycyclic aromatic hydrocarbons (PAH) come from proteins like phenlalanine and creatine, and make over 100 different compounds. The cancer causing effects have been recognized since the 1970’s by the damage to our DNA. Normally occurring at temperatures around 200 degrees Celsius, but they start to occur over 100 C, and peak towards 300C. Direct contact to the heat sources will also increase the mutagen content of foods. They are not very much present in raw foods, 90% of our intake of these come from cooking food.
Sources may include:
Grilled or charred meats or fish, processed and pre-prepared breakfast cereals, refined carbs, fats or oils, and tobacco smoke. We can also get small amounts from fruit of veg if it’s been contaminated in its environment.
Low HCA foods, even when cooked, may include: eggs, milk, legumes and organ meats.
Glycotoxins and advanced glycation end products (AGE’s) come from carbohydrates and sugars, and some proteins, though any foods can produce them when scorched especially when over 230 degrees celsius. They are linked to inflammation, kidney and muscle damage, cancer, insulin resistance and neurodegenerative disease. Unfortunately they seem to taste great and may be addictive. If they are occurring via a dry heat the AGE production may be 10 to 100 times higher! This chemical change is called a Mallard reaction. AGE can also be produced inside the human body from aging or high blood sugar. 3 days after exposure, only 1/3 will have been excreted in the urine. Microwaving may increase AGE more rapidly.
Sources may include: foods made by pasteurization, smoking, drying, frying, microwaving, cooking by BBQ or grilling. Roast chicken is a good example of extremely high intake. High AGE foods include Meats, tofu, butter, processed cream cheese, margarine, mayonnaise, refined oils, roasted nuts.
Low AGE foods are: plant based or raw foods, processing of fried vegan and vegetarian foods will still contain AGE. Tea and yerba mate inhibit the formation of AGE.
Acrylamide is something we also talk about as an environmental exposure agent, but it’s also produced by a Mallard reaction of the protein asparagine with high carb foods in as low a temperature as 120 degrees! Research has shown it to be carcinogenic, neurotoxic and can interfere with reproductive health. A higher temp or longer cooking time will increase the content of acrylamide.
Sources may include: commercially produced foods are among the highest sources. Cereals, biscuits or crackers, chips, fries, pastries, bread rolls and toast, even roasted coffee or chicory. Acrylamide is often found in human breast milk, from food or environmental exposure such as new furniture or body cosmetics. Regular exposure does not guarantee disease, but reduced exposure where possible is highly recommended as these foods are also very low in nutritional value. Learn more about easy ways to be detoxing your home here.
What can we do, and ways to reduce Carcinogens and Mutagens
- Better choices for cooking methods involve slower, indirect heating methods. Consider poaching, stewing, braising or steaming. So a chicken breast cooked in these ways will produce less than 1/9 of the unhealthy compounds that other cooking methods can.
- Consider sprouting, fermenting or dehydrating foods, to make them more digestible without heat exposure. Sprouted quinoa or chickpea’s cook far more quickly which will also decrease mutagens.
- Plant based diets are lower in both HCA and PAH than high meat, whether the foods are raw or cooked, though raw has less again. Roasted nuts are high in carcinogens; raw nuts are low in them and have many healthy compounds.
- Some foods have increased health benefits when cooked, such as tomatoes which have higher lycopene levels, so you do not need to be eating a 100% raw diet, or totally meat free, or very low in carbohydrate.
- Cooking reduces the goitrogen (Thyroid blocking effects) in some foods, so steaming your kale or broccoli at around 100 degrees is still recommended, but frying or BBQing is not.
- Home-made foods have less toxicity, so when you want them have home cooked fries vs commercially produced.
- Naturally occurring acidic marinades may help prevent formation while cooking: choose lemon juice or apple cider vinegar on foods to be cooked. These also help lower inflammation.
- The human liver is able to detoxify both HCA and PAH through phase 1 and phase 2 detox, so your Naturopath may prescribe liver support.
- It sounds obvious, but avoiding all processed foods is just as essential as adjusting our cooking methods. Coffee and toast for breakfast is as unhealthy as a chargrilled steak with steamed veg.
- Tea and yerba mate inhibit the formation of AGE, so drink up those herbal tea’s.
- Increasing nutritional intake through healthy vegetables or supplementation may assist to lower the cancer risk.
- Lower carbohydrate baked goods sweetened with stevia, maltitol or xylitol do not produce as many carcinogens, so in smaller amounts consider these as a substitute for special occasions to have your cake, and eat it too.
- Coconut oil and lard are more heat stable than many other oils, so choose these even with lower heat cooking. Cold pressed oils should not be heated at all: extra virgin olive oil, macadamia, avocado, sesame seed etc. Learn more about good fats here.
- Learning more about angiogenesis, how it contributes to cancer and disease, and what anti-antiangiogenic foods help fights tumours and cancers is highly recommended for everyone not just those diagnosed with a medical condition.
ABOUT THE AUTHOR:
Adv Dip Naturopathy, Adv Dip Western Herbal Medicine
Head Naturopath Kimberly Orbons is passionate about encouraging and empowering each person to facilitate their own good health with Nutrition, Herbal Medicine and preventative lifestyle management. Using a combination of diagnostics and symptomatology to identify the different metabolic processes contributing to disease allows her to treat the root or cause of poor health, providing relief of symptoms and long term recovery.
Kimberly believes it is extremely important to build a personalized healing plan, taking all the complexities of a patient’s health and illness into consideration. Her consults have a strong focus on client care and treating each patient as an individual, and may therefore co-ordinate with other medical treatments. The goal is to establish each patient’s ability to live in the best possible state of health, naturally. Her mentors in clinical practice include Founder Lucy Herron, Dr. David Brownstein, Naturopath Angela Hywood and Dr. Sarah Wine. Since achieving her qualifications in 2007 she has extensive clinical experience, and also 3 years managing the natural health sections and seminar within pharmacy.
Kimberly works closely with our CEO Lizzy Herron, our naturopathic consultants and all The Lucy Rose clinical staff to ensure our patients are provided with the best and most up to date health services and quality health advice. She has actively contributed to our online media, patient guidelines, patient support and informational services for the past 3 years and enjoys providing excellent free to access health data to patients across Australia daily
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