The Specific Carbohydrate Diet

I read through the Specific Carbohydrate Diet website (Breaking the Vicious Cycle). The basic premise of the diet is that proper GI function is dependent on having an appropriate balance of bacteria and microflora. When that balance is damaged, a vicious cycle is started that leads to the failure of the GI tract, GI diseases, and other related diseases stemming from malnutrition and the increase in toxins.

The GI tract has over 400 different kinds of bacteria (5 to 7 lbs of it in fact). Much of that bacteria should be "good" bacteria - organisms that aid in the digestion of foods and creation of vitamins. There are also "bad" bacteria present. These bacteria compete for limited space in your digestive system. These bacteria come into play, in particular, when you eat food that your body can't digest on its own. Whatever bacteria is present will break down and digest the bacteria. Good bacteria does good things while digesting this material. Bad bacteria produce bad things - like gas, toxins, etc.

This is where the "vicious cycle" begins. The good bacteria are lost (likely due to a poor diet or antibiotic drugs that are taken for other illnesses). In the absence of good bacteria, the bad bacteria proliferate. These bad bacteria contribute to inflammation in the GI tract. That inflammation further decreases the digestive tracts ability to absorb nutrients into the body. The lack of nutrition weakens the immune system, decreasing the body's ability to deal with the bad bacteria. The inflammation and change in pH also contribute to the loss of good bacteria.

And then the result of all of this is disease first in the GI tract - Crohn's disease, IBD, collitis - and then disease throughout the body - arthritis, excema, psoriasis, etc. Here's an explanation from the website on the vicious cycle and how it works:

When the balance in the gut is disturbed, an overgrowth of intestinal flora can result. Microbes migrate to the small intestine and stomach, inhibiting digestion and competing for nutrients. The gut then becomes overloaded with the byproducts of their digestion. This bacterial overgrowth can be triggered by overuse of antacids, reduced stomach acidity due to aging, weakening of the immune system through malnutrition or poor diet, and alteration of the microbial environment through antibiotic therapy.

The components of our diet, particularly carbohydrates, play an enormous role in influencing the type and number of our intestinal flora. When carbohydrates are not fully digested and absorbed, they remain in our gut, and become nutrition for the microbes we host. The microbes themselves must digest these unused carbohydrates, and they do this through the process of fermentation. The waste products of fermentation are gases, such as methane, carbon dioxide & hydrogen, and both lactic & acetic acids, as well as toxins. All serve to irritate and damage the gut. There is evidence that increased acidity in the gut due to malabsorption and fermentation of carbohydrates, may lead common harmless intestinal bacteria to mutate into more harmful ones. Further, lactic acid produced during the fermentation process has been implicated in the abnormal brain function and behaviour sometimes associated with intestinal disorders. The overgrowth of bacteria into the small intestine triggers a worsening cycle of gas and acid production, which further inhibits absorption and leads to yet more harmful byproducts of fermentation. The enzymes on the surface of the small intestines are destroyed by the now present bacteria, and this further disrupts the digestion and absorption of carbohydrates, leading to further bacterial overgrowth. As both the microbial flora and their byproducts damage the mucosal layer of the small intestine, it is provoked to produce excessive protective mucus, which further inhibits digestion and absorption.

Damage to the mucosal layer involves injury to the microvilli of our absorptive cells. These microvilli act as the last barrier between the nutrition we take in and our bloodstream. As our absorption is inhibited, folic acid and vitamin B12 deficiency can lead to impaired development of microvilli, while an abnormally thick layer of mucus prevents contact between microvilli enzymes and the carbohydrates we ingest. The small intestine responds to this spiraling irritation by producing more goblet (mucus-making) cells, creating yet more mucus. Finally, as the goblet cells become exhausted, the intestinal surface is laid bare, and is further damaged, and possibly ulcerated. As more carbohydrates are left in the gut, they cause water and nutrients to be pulled from the body into the colon, resulting in chronic diarrhea. Absorption is further hindered as diarrhea increases the rate with which food travels through the gut.

The Specific Carbohydrate Diet is intended to restore the proper balance in your system by 1) starving the bad bacteria, 2) introducing good bacteria, and 3) feeding the good bacteria so that it proliferates.

Here's an excerpt from the website with an explanation from them:

The allowed carbohydrates are monosaccharides and have a single molecule structure that allow them to be easily absorbed by the intestine wall. Complex carbohydrates which are disaccharides (double molecules) and polysaccharides (chain molecules) are not allowed. Complex carbohydrates that are not easily digested feed harmful bacteria in our intestines causing them to overgrow producing by products and inflaming the intestine wall. The diet works by starving out these bacteria and restoring the balance of bacteria in our gut.

The Specific Carbohydrate Diet™ is biologically correct because it is species appropriate. The allowed foods are mainly those that early man ate before agriculture began. The diet we evolved to eat over millions of years was predominantly one of meat, fish, eggs, vegetables, nuts, low-sugar fruits. Our modern diet including starches, grains, pasta, legumes, and breads has only been consumed for a mere 10,000 years. In the last hundred years the increase in complex sugars and chemical additives in the diet has led to a huge increase in health problems ranging from severe bowel disorders to obesity and brain function disorders. We have not adapted to eat this modern diet as there has not been enough time for natural selection to operate. It therefore makes sense to eat the diet we evolved with.

It certainly seems to make sense.