Many people are under the impression that an all raw food diet is a healthier choice than cooked food, but that is not really the case. As a matter of fact, we have been cooking our food for at least 200,000 years and it appears that cooking food, along with eating meat, was one of the primary factors that enabled human beings to develop bigger and better brains and advance as a species.
Research by Dr. Richard Wrangham from Harvard University suggests that our taste receptors are actually designed to “prefer” softer foods, because they are easier to digest, which means we can access our nutrients with less work. Additionally, he demonstrated that cooked food results in about 50 to 95 percent more absorption than raw foods in the stomach and small intestine.
In a study by Herculano-Houzel and Karina Fonseca-Azevedo, at the National Institute of Translational Neuroscience in São Paulo, Brazil, it was demonstrated that a human being would have to eat for 9.3 hours per day in order to provide our brain with enough calories to generate the energy it needs to run properly from raw food. Brain size is determined by its number of neurons and the number of neurons is directly related to the amount of energy (calories) required to nourish the brain. Human brains have more neurons than other primates, and that is because cooking allowed us to consume more energy per day.
You can actually double the nutritional value of vegetables that are high in fat-soluble vitamins like A, D, E and K by cooking them. It is only food that is rich in water-soluble vitamins that loses its nutritional value with cooking, but mostly in overcooking. Carrots, apples, broccoli, tomatoes, asparagus, onions, apricots, celery and spinach are some examples of foods that are high in fat-soluble vitamins. Antioxidants like lycopene, Astaxanthin, lutein and beta-carotene are made bioavailable to the body only when they are released through heat; otherwise they just pass through the body. Other antioxidant compounds called phenolics and flavonoids, which are found in a variety of fruits and vegetables, are also more absorbable when they are cooked.
Furthermore, cooking your vegetables significantly reduces their oxalic acid content. Oxalic acid is a naturally occurring substance that protects the plant from predators, which can form crystals that can deposit in the kidney, muscles and extremities in the human body and result in conditions like gout, muscle pain and kidney stones. It is found in a variety of vegetables like spinach, kale, parsley, chard and collards. Oxalic acid can also bind to calcium and make it inaccessible to the body, which leads to calcium deficiencies.
Cooking also significantly reduces goitrogens, which are substances that are found in the cruciferous family (cabbage, broccoli, cauliflower, kale, brussel sprouts) that can disrupt iodine metabolism and thyroid hormone production, and lead to a whole host of problems like weight gain, fatigue, brain fog, and more.
Additionally, cooking reduces the presence of anti-nutrients in vegetables that may inhibit absorption of important minerals, which will increase the mineral content of cooked over raw.
This means that if you are consuming an all raw diet you are at high risk of developing complications with your thyroid, insufficient iodine levels, kidney stones, gout, muscle pain, and calcium deficiencies. Other problems associated with an all raw diet include an excess of tooth decay and other dental issues, gastrointestinal distress, nutritional deficiencies (especially B12, K , D, selenium, zinc, iron, and the fatty acids DHA and EPA), and an increase in homocysteine and decrease in HDL, which can contribute to heart disease.
Proponents of the raw food diet claim that cooking will destroy the enzymes present in your food, while that is true, enzymes are also destroyed in your stomach when they come in contact with hydrochloric acid, so the point is moot. Not only that, enzymes that are present in fruit and vegetables exist for the benefit of the plant, not yours; they are not needed to enhance human digestion.
Most advocates of a raw food diet are subsisting on fruits, vegetables, nuts and seeds alone, and abolishing animal protein. As you know if you’ve read other pages on my site, animal protein is absolutely essential for a healthy mind and body. Human brain development and advancement of the species would simply not have been possible without the consumption of meat. It was meat that enabled us to exchange a bigger digestive tract for a bigger brain and it allowed us to advance into more climates where vegetation was not widely available. We could acquire more nutrients and calories with less effort. It takes a great deal of energy for the human brain to run and meat was the most accessible form of fuel available.
No culture in the history of human kind has ever survived on a raw food only diet. If you attempt to do so, without extensive nutritional supplementation, you are headed for troubled waters.
Does that mean you should never eat raw foods? No, of course not. Enjoy your raw salads, avocados, fresh berries and other fruits, but don’t be afraid of cooking either. Some foods like nuts, seeds and dairy products are more nutritious and healthier in their raw state. Many feel that eggs are best consumed raw, but only if organic and cage-free. A healthy Paleo diet will consist of a combination of both cooked and raw foods.
So why do you hear a variety of people singing praises for a raw food diet? Because most people who are switching over to raw are leaving the standard American diet behind and any change away from the SAD diet will likely result in some improvements of health. However, these improvements are not going to be long-lasting, and in time degradation of health is inevitable. Indeed, you may lose weight on a raw food diet, but that is because you are depriving your body of valuable nutrients, this is not healthy weight loss and will ultimately lead to new problems.
However, your method of food preparation is important; you shouldn’t boil. Boiling permits the nutrients to get away. The preferred manner for cooking vegetables is to steam them. Steaming preserves most nutrient content and alkalinity. You can also drink the liquid that is left in the pan after steaming, which holds a lot of the nutrients that were released during cooking.
An occasional sauté or stir fry would be acceptable as well.
Another option is to bake them in a covered dish. For example, peaches or apples sprinkled with cinnamon, would be nutrient packed and tasty. Veggies in the crock-pot with a savory meat dish is another excellent choice.
Your meat is best baked, broiled or slow roasted; it should never be burnt.
Yes, indeed, overcooking, boiling something to death, and char-broiling, can deplete minerals and create cancer causing agents, but baking, broiling, crock-potting, steaming, sautéing or stir frying are your friends. Use them freely.
References
The Importance of Cooking in the Evolution of the Human Brain
The Evolutionary Role of Cookery, Feb, 2009.
Can a Raw Diet Make You Sick?, Kelly Herring
“The Journal of Nutrition”; Long-Term Consumption of a Raw Food Diet Is Associated With Favorable Serum LDL Cholesterol and Triglycerides But also Elevated Homocysteine and HDL;Corinna Koebnick et.al.; October 2005
https://jn.nutrition.org/content/135/10/2372.long
Cynthia, thank you for another intelligent and well-written article on a complicated and misunderstood topic. I very much enjoy reading your posts. Wishing you a fantastic day.
Hey Greg,
Thank you and you are quite welcome. Have a beautiful Thanksgiving.
Cynthia
Thank you so much for writing this article. The myth that raw foods are ‘so easy’ to digest is still so common. It’s maddening! For many of us with gut and metabolic issues eating raw vegetables feels like eating ROCKS. It also makes our digestion and nutrient absorption far worse, so it’s very bad advice to be given to ill people especially. Cooked vegetables are also just so much nicer to eat. Thanks again, I’m a big fan and wish you every success.