Many people have asked me about the benefits or drawbacks of raw versus cooked foods. So I have written this article to try to give an explanation and bring some clarity.
In discussing this I have focused only on plant-based foods, as they represent the major component of the food choices recommended by many of the natural and holistic approaches to cancer. Such approaches have been used by most of the people who have chosen to heal themselves of cancer through natural methods rather than follow conventional medical therapies centered on chemotherapy, radiation and surgery.
Partial Analysis Only
Based purely on scientific studies it is very clear that comparing the healthfulness of raw versus cooked food is complicated. The scientific analysis is founded on measures of certain components of the foods based on its raw state or following particular cooking methods. This ‘partial analysis’ may only be the tip of the iceberg in terms of the food’s overall nutritional value and contribution to our state of health, or ability to assist with disease prevention or to help with overcoming disease.
I use the phrase ‘partial analysis’ because many people are not convinced that science has yet discovered every conceivable type of molecule that exists within each type of food, and also there are still many mysteries surrounding how the different molecules in plants interact with the human body.
In addition foods contain a complex of different molecules and nutrients that work together in a synergistic way. Extracting and analyzing the presence of just some of those nutrients in isolation may not necessarily be a valid measure of how much that particular food item, either in its cooked or raw state, contributes to our health.
Both Advantages and Disadvantages
Many people seem to have fixed opinions about raw versus cooked food. Some say that cooking destroys nutrients, enzymes and the “life force” of the food itself. Others say that some nutrients, and potentially beneficial plant compounds, are less available to the body in the raw state, and that heat is needed to break down a plant’s cell walls and release the compounds. In fact both views are correct, depending on what is being measured or assessed. To add to the complication, there are well known variances between different plant foods.
Beta-Carotene, Lycopene, Vitamin A
Dietary carotenoids (such as beta-carotene and lycopene) are associated with a reduced risk of chronic diseases, and are derived mainly from plant foods. Both vitamin A and carotenoids are nutritional components of high interest in many studies due to their numerous biological roles in health and disease. Also in many studies, a high intake of lycopene (the red pigment found predominantly in tomatoes and other rosy fruits such as watermelon, pink guava, red bell pepper and papaya) has been associated with a lower risk of cancer and heart attacks
A study in Germany, published in the British Journal of Nutrition, analyzed 198 people (ninety-two males and 106 females) on a strict raw food diet that represented 95% by weight of raw food intake, to determine the diet’s effect on blood levels of vitamin A and carotenoids. The raw food diet was made up of fruits and some vegetables, and the consumption of bread, cereals, rice, potatoes, legumes, dairy products, visible fats and oils was negligible.
Here are the main findings of the study:
- Higher blood levels of beta-carotene were achieved through adherence to the raw food diet
- The most important dietary factor predicting vitamin A and carotenoid plasma concentrations in people on a raw food diet was fat and oil consumption
- Carotenoid absorption increases when carotenoid-containing salads are eaten in combination with a full-fat dressing rather than using low-fat dressings
- There was not a high correlation between blood levels of carotenoids and cooked versus raw vegetables
- Raw food consumption and lack of cooking negatively affects blood lycopene concentrations
The main conclusion from that study is that cooking will increase lycopene levels but have very little effect on other carotenoids and Vitamin A levels. Also, it is advisable to consume added fats as part of a raw food meal to optimize carotenoid absorption.
Anti-oxidants and Vitamin C
In another study published in the Journal of Agricultural and Food Chemistry done at Cornell University, it was reported that cooking tomatoes elevated total antioxidant activity and bio-accessible lycopene content in tomatoes and produced no significant changes in the total phenolics and total flavonoids content, although loss of vitamin C was observed.
Another study in Italy published in the Journal of Agricultural and Food Chemistry evaluated the effect of different cooking methods – boiling, steaming and frying – on the nutritional content of vegetables. It showed that frying vegetables resulted on the lowest retention of antioxidant compounds compared to boiling and steaming.
Other research shows that some vegetables, including broccoli, are healthier raw rather than cooked. According to a study published in the Journal of Agricultural and Food Chemistry in November 2007, heat damages the enzyme myrosinase, which breaks down glucosinates (compounds derived from glucose and an amino acid) in broccoli into a compound known as sulforaphane. By damaging the enzyme myrosinase it is unable to make sulforaphane, which is an important compound in killing precancerous cells and controlling the Helicobacter pylori bacterium.
Another study found that boiling carrots leads to a total loss of polyphenols, a group of chemicals found in raw carrots. Specific polyphenols have been shown to have antioxidant properties and to reduce the risk of cardiovascular disease and cancer.
The balance of evidence does seem to be stronger in favor of raw vegetables than it does for cooked vegetables. If we consider that almost all of the natural protocols that people have followed to overcome their own cancer are based on raw foods, it is also a strong indication of its likely effectiveness. However the scientific evidence concerning raw versus cooked is mixed, as is often the case in scientific studies. They can only analyze tests of certain components of fruit and vegetables that they set out to evaluate.
It is certainly well known that a diet containing more fruits and vegetables (whether raw or cooked), will help lower your risk for certain types of cancer, according many reviews published in “Cancer Epidemiology, Biomarkers & Prevention“.
The Bill Henderson Protocol recommends a combination made up of 80% raw versus 20% cooked. By doing that it is more than likely that the benefits of both raw and cooked will be obtained.