Deadly Harvest: The Intimate Relationship Between Our Heath and Our Food (24 page)

Nutrition researchers Robert McCance and Elsie Widdowson formed a remarkable partnership for over 60 years. They established the specifications for British wartime rations during World War II and the British nation has never been healthier since that time, when the portions of food were metered with tight discipline and only foods essential to the human body were made available. McCance and Widdowson worked out indexes of acidity and alkalinity for many foods.
¹²⁸

Select Acid/Alkaline Indexes

So, what pattern of eating does this imply? Notice that the acid-forming foods (mainly proteins) are
dense
compared to the alkali-forming ones (mainly non-starchy plant food). That is to say, the plant food is more watery than the proteins. We also see how in today’s diet, starches, which are acidic, displace other kinds of plant foods that are alkalizing.

On average, it takes three times as much plant food as protein to maintain a neutral balance; in other words, about 75% by weight of plant food to 25% of protein in the diet. This same ratio also provides the right amount of protein in the diet, neither an excess or a deficit. Have we seen this ratio before? It is not a coincidence that both the San and the Australian Aboriginal consumed a very similar ratio of plant food to animal food. This is another piece of evidence confirming the natural adapted eating pattern for human beings—one in which non-starchy plant food occupies about three-quarters of what we eat and foods of animal origin about one-quarter.

Summary—Biochemical Clues

We have delved into how the food we eat is a major influence on the human body’s biochemical processes. It is a complex subject and our knowledge is far from complete. We cannot predict with certainty that what we do today will have the same results tomorrow. This reinforces our idea that, perhaps, we should not even be trying to micromanage these processes. Instead, we should simply consume the foods that our body expects and it will sort these matters out for itself.

Chapter 5

The Science II: Digestive System and Dietary Clues

In the last chapter, we looked at scientific studies on human populations around the globe and investigated how their different diets affected their health and life span. We also looked at the way our biochemistry is supposed to work and the consequences for our food choices. Here, we examine the way nature has designed our digestive system to work and what this tells us about the foods we should be eating. Then, we will look at what our modern diet is doing to us.

DIGESTIVE SYSTEM CLUES

What process can be more intimate than this: absorbing foreign agents into the most secret parts of our bodies? It is remarkable how little we think about this process, for that is what eating is—infiltrating stuffs from our mouths into the very fiber of our being. The mechanics are performed by the digestive system, which can be thought of in two major parts: the physical digestive tract (mouth, stomach, and intestines) and the complex array of enzymes, juices, and hormones (secreted by the pancreas, liver, and the digestive tract itself) that make it all work.

We’ve talked previously about the “chaotic” complexity of our body’s systems, and the digestive system is no exception. Signals reverberate between the digestive tract, the pancreas, liver, and brain. Hormones and nerves are constantly relaying messages to our brain and back again to the digestive system and organs communicate with each other using hormones and nerve signals. It all works automatically, entirely without our knowledge. When it works well, our bodies hum along like finely tuned machines. However, when it goes wrong, then we can learn from the dietary errors that caused the malfunction. By looking at the digestive tract and how nature intended it to work, we can draw lessons about how we should be eating.

The digestive tract of all mammals, including humans, is built to the same basic plan—it begins at the lips and ends at the anus. Digestion begins in the mouth with its teeth, for grinding the food, and its tongue, which kneads the food and mixes it with saliva. It then sends the pellet of food down to the stomach. On its way there, it passes through the long tube called the esophagus or gullet. At the entry to the stomach, the food passed through a non-return valve. This is to stop the stomach contents from accidentally passing back up into the mouth, although in emergencies this mechanism is suspended to reject any substances that the stomach detects as harmful.

The stomach is basically a holding reservoir where the food is churned with hydrochloric acid to kill any harmful bacteria. A secondary role is to secrete a mixture of enzymes to begin digestion of proteins and fats. From there, the mixture (chyme) passes through another non-return valve (the pylorus) into the small intestine. Once past this gate, it is impossible for the chyme to come back into the stomach. The small intestine is just over one inch in diameter and about 23 feet long. Here, most of the food is mixed with various digestive juices and enzymes and absorbed into the bloodstream. The remaining, unabsorbed food residues pass through another non-return valve into the large intestine or colon, which is about 5 feet long. Here, excess water and various nutrients are absorbed into the bloodstream.

The Underrated Colon

The colon until recent years has been a much underrated organ, even thought to be dispensable. We now know that the colon performs many essential functions when in a proper state of health. Today, diseased colons cause a wide range of illnesses. So, we now examine what makes the colon function properly and, in this way, better understand what kinds of food residues we should be putting there.

We are all walking around with 3 to 5 pounds of living matter (“biomass”) in our colons: bacteria, yeast, and fungi. Collectively, they are known as gut “flora” (from the Latin word for the Roman goddess of flowers). There are over a trillion bacteria alone, of many and varied species. Most of them are “anaerobic”—they do not need oxygen in order to survive. They live on the food residues that arrive in the colon. For example, many kinds of carbohydrates survive digestion, particularly plant fiber and the very complex carbohydrates.

Through fermentation of these food residues, this biomass produces all kinds of useful compounds. Fatty acids called butyric acid and propionic acid are absorbed through the colon wall into the bloodstream, where they carry out important functions in the body, such as boosting immune function and controlling cholesterol. Gases like hydrogen, carbon dioxide, and methane are also produced and, in part, pass into the bloodstream. (The other part is passed as wind.) From the blood, the gases pass to the lungs where they are breathed out. However, even bacteria have difficulty breaking down some indigestible compounds, such as lignin (a woody fiber) and cellulose. These are passed out, unaltered, in bowel movements.

We should consider this biomass as an important organ. French gut specialist and researcher M.C. Moreau says that the mucous membrane lining the gut is the largest immunological organ of the body.
¹²⁹
Remarkably, these gut organisms communicate with elements of the immune system, a phenomenon known as “cross-talk.” For example, lymphocytes are white blood cells of the immune system that do not mature and work properly unless the colon flora stimulates them.

For the colon’s cargo of flora to thrive, it needs to be fed with plant fiber: viscous (soluble) fibers such as pectin, guar gum, and beta-glucan, which are the building materials of plant cell walls. We are not talking about insoluble fiber as found in cereal brans (a partial exception is oat bran). Researchers have discovered the many benefits of a high consumption of viscous fiber from plants:
¹³⁰
it has a lowering effect on “bad” LDL cholesterol levels and it reduces mutant cells in the bowel and free radical damage.

Free Radicals and Antioxidants

Free radicals are highly aggressive molecules that the body creates continuously as a by-product of various chemical reactions. Outside agents such as ultraviolet rays, tobacco smoke, and alcohol also trigger them. Free radicals can cause a lot of damage to cells and DNA.

A free radical is a molecule that contains at least one electron that is looking for a partner. Because of this, free radicals vigorously react with whatever they encounter. At worst, they tear open intact molecules, cannibalizing parts of them to complete their own electron partnership. This creates new partnerless electrons and so the attacked molecule becomes a new source of many free radicals. In this way, an exploding chain reaction is set in motion that can cause damage out of proportion to the initial provocation.

The body quenches free radicals by the use of antioxidants, micronutrients that neutralize free radicals and the damage they cause. There are many antioxidants in plant foods but they are rarely found in animal products. Antioxidants have the ability to put a stop to the free radical chain reaction. Food antioxidants include vitamin C, vitamin E, zinc, and selenium. Other antioxidants are “background” micronutrients, such as quercetin, resveratrol, and anthocyanin.

The benefit is a reduced risk of colon cancer. Bowel movements are more massive and they pass more quickly through the system: constipation is eliminated and diverticulosis (abnormal balloonings in the gut wall) is avoided. The viscous fiber also locks up harmful compounds and evacuates them. For example, estrogen isoflavonoids are chemicals in plants that can affect the same tissues as human estrogen, but can produce very different effects.
¹³¹
They are found in some plants such as soy. These phytoestrogens are not always such a good thing, for they are implicated in lung and breast cancers.
However, in a high-fiber diet, these phytoestrogens are safely ushered out of the body.

Other foods, like hot peppers, cause the lining of the intestine to become more porous, a condition known as leaky gut syndrome. It does not take much: the gut wall is as thin as tissue paper and that is all that separates the sludge in your gut from your blood circulation. Even under good conditions, there are always
some bacteria that pass through into the blood. For example, primitive herders knew to starve a beast for 24 hours before slaughter, because there would be fewer bacteria generalized throughout the carcass and the meat kept longer.

Herbs and Spices

Herbs and spices are usually rich in aromatic micronutrients, which accounts for their pungent flavor. This is all to the good, yet normally the quantities we eat are an insignificant part of the diet. For this reason (we suppose), the U.S. Department of Agriculture diet guide for 2005 has nothing to say about them. We do not give them a high profile either.

Nevertheless, there is one class that has powerful effects on our digestive system: the hot pungent ones, such as chili pepper, cayenne pepper, and paprika. Austrian researchers found that chili has a provocative effect on irritable bowel disease.
¹³²
Dr. Rodriguez-Stanley found that heartburn (“acid reflux”) was acutely increased too.
¹³³
Dr. Erika Jensen-Jarolim found that chilies, and to a lesser extent paprika and cayenne pepper, make the colon “leaky.”
¹³⁴
She found that large molecules could then pass through the colon wall into the bloodstream, giving rise to allergies, a depressed immune system, and increasing chances of colon cancer. However, black pepper was harmless.