Among our many blessings as humans is the ability to enjoy food. Since our bodies function as energy consuming machines, we have to burn fuel every minute of every day to supply that energy. Our intake of food provides the fuel we have to have to stay alive. Our survival as a species depends upon the fact that we enjoy eating. If it were not so, it would be possible to “forget” to refuel in time and run out of fuel. If we were to run out of fuel, we would die. It seems simple enough: we require fuel to keep the “life fire” burning, the fuel we need is available in the form of food, food is available, we enjoy eating, so all we have to do to stay alive is to eat – to do something that we enjoy.
Yet what appears to be the simple act of eating is actually very complicated. When we take food in our mouth, we chew it, which begins the complicated process of digestion, involving neural reflexes, secretion of multiple enzymes, and absorption of nutrients, medicines, poisons, and liquids.
The act of chewing mixes the food with the first of many digestive enzymes, salivary amylase. The various enzymes involved in digestion break the fuel down into a form that can be absorbed and utilized as fuel and for other purposes. Chewing and swallowing trigger a neural reflex known as the oro-gastric reflex, preparing the stomach to receive the food bolus, stimulating gastric juices and beginning muscular activity designed to further mix the food and reduce it to a more nearly liquid form. When the food is in a more nearly liquid state, the pylorus opens little by little to allow contents of the stomach to pass into the duodenum where further enzymatic action breaks the food down into molecules that are absorbed by specialized cells lining the gut. The way we are made, the entire circulation of the gut, containing every molecule that has been absorbed, passes directly through the liver. The liver’s job is to examine every molecule as it passes through and determine what to do with it – convert carbohydrates, fats, and proteins to glucose, detoxify if it’s poison, store in the form of glycogen, metabolize and synthesize into hormones, combine to form low density or high density lipoprotein cholesterol, or other essential molecules. The liver has to be healthy for these functions to proceed normally. When the stomach performs as it is designed to do, the contents of a meal enter in the form of a semisolid mashup of chewed and swallowed food, saliva, and liquids swallowed with the meal. As the stomach churns and mixes with gastric secretions and acids, the pylorus very slowly releases small amounts of the increasingly liquid stomach contents into the duodenum, leading to a relatively slow absorption of the nutrients, the sugar, protein, fat, and other elements of the meal. The liver is designed to accommodate that kind of relatively slow absorption and performs its function well.
Now think of what happens when the food is actually a liquid, as in when a person “juices” it before swallowing it. (Or Shakes or Smoothies) First there’s no chewing and consequently no mixing with salivary amylase, the pro-gastric reflex is blunted so the stomach is not prepared to receive the food. Since the food is already in a liquid form, the stomach does not churn and mix with gastric juices to convert it to a liquid, and the contents now are rapidly passed through the pylorus into the duodenum with the nutrients now being much more rapidly absorbed and delivered to the liver much more abruptly. The liver, which had been at rest, now suddenly is presented with a much larger workload than would have been the case if the food had not bypassed the mastication and mixing with saliva phase. As a result, the liver may find itself overworked and unable to perform its function, leading some cells to burst or otherwise be damaged. These cells may ultimately be replaced by fat – so-called fatty infiltration of the liver. This can also be described as “liver shock” and results in the inefficient utilization of food that can play a role in everything from diabetes to irritable bowel disease, from indigestion to cancer.
Now, the modern American diet consists of 1.) a much larger amount of food than was the case a generation ago, 2.) much of it processed and fortified with artificial preservatives, flavorings, and color, (junk food) and 3.) a large amount of sugar (sucrose) either as an additive in the case of processed food, or directly in the form of dessert sweeteners. Taken together, this presents a real challenge for the liver. The volume of food leads to more work. The content of the food requires more work (the liver is responsible for breaking down the various poisons – the preservatives, artificial flavors, and artificial colors) and there is a large amount of sucrose to deal with. Sucrose is a manufactured product consisting of a molecule of glucose and molecule of fructose in a covalent bond. Humans are not designed to ever encounter a molecule of sucrose because it does not exist in nature; the per capita yearly consumption of sucrose in the United States is now amazingly around 100 pounds. The liver has to break the sucrose down into glucose and fructose before otherwise utilizing it. All these forces come to bear upon the liver’s ability to function and ultimately may lead to fatty degeneration or “Non-alcoholic Fatty Liver Disease.” Until recently, the number one cause for liver cirrhosis and liver failure in the US was excessive consumption of alcohol, which damaged the liver by requiring it to detoxify a large amount of alcohol with the subsequent formation of various toxic metabolites. Nowadays the number one cause for liver failure in America is nonalcoholic fatty liver disease!
So, don’t juice your diet. Don’t rely on shakes or smoothies. Eat real food. Save your liver. Slow down and savor your food the way God intended. Chew with an open mind – and again, real food as opposed to processed.