01.06.2015 Nutrition

Eat More Raw

Evidence is mounting that eating more raw, plant-based foods is a big boost to health, says researcher Peter Dingle PhD

The thought of eating nothing but raw food seems somewhat alien in the modern world where the methods of cooking food are widely varied. But until the discovery of fire - and the ability to recreate fire was developed around 1.8 million years ago - our human ancestors consumed massive amounts of raw food. It has been estimated that throughout 99% of human evolution, we consumed nothing but raw foods - something that is hard to imagine.

Humans are the only species (if you don't count our domesticated animals) that don't eat a 100% raw food diet, with many populations eating a diet consisting almost entirely of cooked and processed foods. Undomesticated and wild animals live on a completely raw food diet and suffer few of the serious degenerative conditions that we humans do.

The paleo diet (ie the Hunter-Gatherer Diet), has received a lot of attention in the media recently for its proposed health benefits. But we humans are much more, in evolutionary terms, than the early cave (paleo) man. It is on the right track but less than 5% of the evolutionary history of man has been as bipedal hominids, walking tall on two legs. We have been using tools to grind, prepare and cook food for less than 1% of our evolutionary history. We are, in fact, well and truly pre-pre-paleo-raw food eaters if you look at our history. Additionally, it has only really been over the last 1000 years that we humans have been processing our food, something that has really taken off in the last 100 years and even worse in the last 50 years with modern junk foods and takeaways.

Humans are unlike any other primates. If you spent the day watching any one of the great apes, our closest evolutionary cousins, you would see that they spend most of their time eating raw fruits, vegetables and leaves, chewing each mouthful for minutes. Gorillas and orangutans are almost entirely herbivorous (plant eating) and while chimpanzees eat mostly plant foods, including fruits, seeds, nuts, leaves and flowers, they will also eat insects and even more rarely hunt larger animals (around 2% of their diet). All of their food is raw. Now I am not recommending you go out and eat your meat raw, but there is a lot of merit in increasing the raw component in your food.

If you look at the evolutionary history of humans and the dietary habits of our closest relatives, the great apes, it seems that we have a digestive system that has evolved to ingest and break down raw foods. So why don't we eat them more?

Health benefits of raw food

At both a personal and scientific level I have no doubt about the health benefits of increasing the raw component in your food. There is growing scientific evidence that a higher consumption of raw, plant-based foods is beneficial to human health. Increased consumption of raw foods can lead to a reduction in allergies and strengthening of the immune system. As a result, the risk of cancer and other chronic diseases is reduced. Other health benefits such as a lower Body Mass Index (BMl), lower blood pressure, and beneficial levels of lipids, lipoproteins, glucose, insulin, HDL cholesterol, LDL cholesterol and triglycerides can also be attributed to raw food consumption. Raw diets lead to a decrease in obesity and cardiovascular disease through less consumption of processed carbohydrates and sugars. All of the people I have encouraged to consume more raw food, usually through having a vegetable smoothie, have lost weight and reported more energy. An increase in raw vegetable protein also decreases bone loss and the risk of bone fractures.

In a study of blood pressure for 2,195 participants, intakes of both total raw and total cooked vegetables were inversely related to BP. However, the study found raw vegetables had a stronger effect on blood pressure than cooked vegetables. In a study that followed 32 individuals on diets containing at least 40% uncooked foods (vegetables, seeds, nuts, fruits, and certified raw milk) for six months, intakes were significantly associated with lower blood pressure of participants but increased to previous levels when switched from high raw food diets back to cooked diets (without altering caloric or sodium intake).

You might recall the raw blood pressure smoothie I wrote about last year. (See it here at http://novamagazine.com.au/article_archive/2014/2014-05-lower-blood-pressure-without-drugs.html)

Just by having a raw vegetable smoothie people's blood pressure dropped by as much as 50 mmHg. Such large drops in blood pressure are unheard of in medicine. A recent cohort study of 20,000 men and women in the Netherlands using food frequency questionnaire data on seven raw vegetables and 13 cooked vegetables, reported that raw vegetable intake was significantly inversely associated with ischemic stroke, and raw fruit and vegetable consumption was also inversely related to coronary heart disease.

Studies of patients suffering fibromyalgia showed a marked improvement in their condition after following a raw food diet. Improvements included better sleep and digestion, along with less pain, fatigue, anxiety and depression. The reversal of chronic metabolic acidosis, as well as improvements in people suffering from diabetes, can be achieved through a raw diet.

A raw food diet also results in numerous mental benefits. Eating raw foods leads to better sleep and hormone regulation. One report found that patients who were suffering from anxiety, depression and eating disorders showed significant improvement in their condition after beginning a raw food diet.

Overall, raw food has the potential to have a major positive impact on our health and our lives. The benefits are derived not just from the additional nutrients and improved digestion, but also from exposure to a lower level of cooking based toxins.

Less strain on digestion

Predigestion by food enzymes occurs in every creature on earth; the only exception is humans on a cooked, enzyme-deficient diet. When we eat raw foods, physical contact, heat and moisture in the mouth activate the enzymes in the food. Once active, these enzymes digest a significant portion of what we ingest.

The stomach has two distinctive sections, the upper Fundus and the lower Pylorus. The bolus of food remains in the upper part, the Fundus, for up to one hour where predigestion of raw foods takes place. All raw foods come with their own digestive enzymes, thus saving the pancreas from supplying all the enzymes needed for digestion. You don't want to waste too much of your "life force". Cooked foods, which have no enzymes as they break down at around 48oC, must wait in the Fundus and can only rely on enzymes from the pancreas, which means a lot more work for our body, and the feeling of fatigue after eating a big cooked meal.

There are two zones of protein digestion in the stomach. One has a pH of 1-2.5 at which the enzyme pepsin is most active. The other zone has a pH of 3.3-4 at which the enzymes naturally occurring in raw foods are still active. The amount of digestion in both zones is approximately equal. For example, raw meat has its own supply of cathepsin so if you eat raw meat like all other carnivorous or omnivorous animals, up to 50% of the digestion occurs before it even comes in contact with the pepsin from the gut.

The same happens with plant-based proteins. Digestion can continue without the use of our body's own digestive enzymes when the pH changes in the intestines allowing the food's natural digestive enzymes to become active again.

Enzymes are essential for the digestive process and when food is cooked the naturally occurring enzymes are destroyed, meaning that the digestive system has to work so much harder to digest food. Additionally, digestive enzymes help to cleanse our colon; foods that are not digested properly are stored in our colon and digestive problems can begin.

Signs of enzyme deficiency

The most obvious symptoms of enzyme deficiency are easily identified, particularly after meals, and can include:

Acid refluxHeartburnBloating, gas and crampingConstipation and poor eliminationDiarrhoea

Cooking food can have a negative effect on digestion, both by destroying enzymes and other nutrients that aid in the digestive process and through heat and processing reducing the amount of co-factors and co-enzymes, which are essential for efficient digestion. Co-factors are inorganic micronutrients such as zinc, iron and copper, which are important for the function of many digestive enzymes. Co-enzymes are organic molecules, such as vitamins, that also assist in digestion.

Digestive enzymes cleanse our colon. Foods that are not digested properly are stored in our colon and digestive problems can begin. Undigested protein putrefies, carbohydrates ferment, and fats turn rancid in our colon. Unpleasant isn't it?

The enzymes from live raw foods prevent this from happening. Excess enzymes from these foods can also be absorbed into the blood and assist with numerous health conditions, including attacking cancer and viruses.

Poor or inefficient digestion can cause a number of health conditions, ranging from arthritis to Alzheimer's, to cardiovascular disease to cancer, as well as diseases of the digestive system.

An estimated 40% of Australians have lower gut disorders and one in five Australians is known to suffer from irritable bowel syndrome, and the number is on the rise. Other conditions of the digestive system include: colitis, Crohn's disease, leaky gut, gluten intolerance, bloating, acid reflux, heartburn, constipation, diarrhoea and food allergies. Other health problems that can develop as a result of poor digestion include: fatigue, yeast overgrowth, acne, depression, obesity, high blood pressure, circulatory problems, chronic inflammation and auto-immune disorders.

Enzymes are literally the life force and it is well established the greater the supply of enzymes you have in your body, the slower you will age and the more resistant you are to degenerative diseases. In general, the duration of life varies inversely with our enzyme activity and the older we get, the weaker our enzyme activity becomes. This is not just an indication of lost enzyme potential, but a reduction in the enzyme potential of the whole body, both digestive and metabolic.

If you take your health seriously I suggest starting with a raw plant-based smoothie each day. You might be surprised at not only how good it is for you but also how quickly you can make it.

Breast is Best

Milk provides a good example of how cooking and processing a foodstuff can greatly affect its nutritional value. While raw milk is a complete food for infants of all mammalian species, it loses many of its qualities when heated and is no longer a good food for infants of any species. As well as the normal losses of vitamins and other nutrients that occur from cooking milk, all the enzymes are destroyed too. There are more than 20 different enzymes in milk, which help aid in its digestion, including those that digest calcium and break down lactose and casein. If lactose and casein are not digested properly, it can lead to serious problems, including lactose intolerance and leaky gut syndrome.

At birth, babies do not come fully equipped with all their own digestive enzymes. This allows energy and nutrients to be used to produce the metabolic enzymes needed for growth and repair. Destroying all the naturally occurring digestive enzymes in milk causes the baby's own enzyme factory to begin using its enzyme potential from day one, putting stress on the pancreas and increasing the likelihood of long term digestive problems. Research has suggested that there is a link between pasteurised milk and type I diabetes, multiple sclerosis and many other chronic health conditions and gut problems.

If babies are given pasteurised milk or cooked foods, their digestive systems will struggle. This reduces the availability of nutrients and increases toxins in the gut, including undigested protein molecules. These protein molecules can be absorbed by a damaged gut and cause allergic reactions, which may be the root cause of many of the digestive tract problems identified later in life.

A study involving 20,061 babies that were divided into three groups (breast-fed, partially breast-fed, and bottle-fed), showed the effect of processed milk of health. They studied the morbidity (sickness) rate for the first nine months of the infant's life. They found that 37.4% of the breast-fed babies had sickness in comparison to 53.8% of the partially breast-fed and 63.6% of the bottle-fed.

DISCLAIMER: Dr Peter Dingle is a researcher, educator and public health advocate. He has a PhD in the field of environmental toxicology and is not a medical doctor.


Peter Dingle

Dr Peter Dingle (PhD) has spent the past 30 years as a researcher, educator, author and advocate for a common sense approach to health and wellbeing. He has a PhD in the field of environmental toxicology and is not a medical doctor. He is Australia’s leading motivational health speaker and has 14 books in publication.