Amazing Digestive System Design

Amazing Digestive System Design
The Human Digestive System

The Tufts University Health and Nutrition Letter for March 2022 has a great article titled “Your Amazing Digestive System.” It explains in great detail what happens to food from the time you look at it until it leaves the body. We take for granted what happens when we eat food, but the amazing digestive system is so complex that it is another extraordinary evidence of God’s wisdom and design. Consider the parts of the system as spelled out by the Tuft publication:

THE GASTROINTESTINAL TRACT: This tube runs from the mouth to the anus with a lining separating the food we eat from the inside of our body. Muscles and nerves control the speed of movement of the food, and nutrients are absorbed through the tube wall, which controls what nutrients are absorbed and how fast.

THE MOUTH: The smell and sight of food stimulate the secretion of saliva (which is why our mouths water), moistening and lubricating the food so we can swallow it. The saliva has an enzyme called salivary amylase, which begins to break down starches as the teeth grind the food into more digestible pieces.

THE ESOPHAGUS:
This tube is about a foot long and connects the throat to the stomach. It has muscles to push the food along and a valve that opens to let the food enter the stomach.

THE STOMACH: When food enters the stomach, gastric acid and digestive enzymes break down proteins and kill unwanted organisms. Stomach muscles contract and relax, reducing the food to a diluted paste.

THE SMALL INTESTINE: Most nutrients are absorbed here, including proteins, carbohydrates, fats, and micronutrients. This tube is about 20 feet long and an inch in diameter. The small intestine uses enzymes from the pancreas and bile from the gallbladder to break down the food. There are three sections to the small intestine, the duodenum, the jejunum, and the ileum, each absorbing different nutrients.

THE LARGE INTESTINE: Also called the colon, this muscular tube is three times wider than the small intestine but only about five feet long. The colon absorbs beneficial nutrients not previously absorbed. Anything the body can’t use is passed on to the rectum. The large intestine also absorbs water and has a complex organization of bacteria called “gut-microbiota.” Those microbes use fiber to produce beneficial compounds and produce many hormones required for our immune system.

Our amazing digestive system design defies any chance explanation. Each precisely designed part is an essential contributor to our ability to eat and digest food. It is no wonder that so many diseases can negatively affect the digestive system. It is hard to read all we know about this system and not be reminded of Psalms 139:14, “I will praise you, God, for I am fearfully and wonderfully made: marvelous are your works and that my soul knows very well.”

— John N. Clayton © 2022

Reference: Tufts Health and Nutrition Letter

Healthy Microbiome Design

Healthy Microbiome Design

The colonies of microbes living on and in our bodies make up what is called our microbiome. The bacteria outnumber our own body cells by a ratio of ten to one. Your body is host to 100 trillion bacteria of at least 10,000 different species. Before you start to worry about that, most of the bacteria will not hurt you. More than that, you couldn’t live without a healthy microbiome.

Some bacteria are essential to make our immune system work to prevent infection. Others make it possible for us to digest the food we eat. Bacteria are on our skin, in our lungs, in our mouths, especially in our gut. Your digestive system needs a good balance of bacteria for proper digestion. Some medical experts think that an imbalance of gut flora (bacteria) leads to irritable bowel syndrome and Crohn’s disease.

There has been a boom in sales of probiotics in pills, liquids, and yogurts in recent years. These contain bacteria that may help your digestive system, but the amounts and types of bacteria may not necessarily be the ones needed for your system. Everyone has a somewhat different microbiome, and, as we recently posted, it all starts in our mother’s womb. Breastfeeding further adds beneficial bacteria to the baby’s flora.

When we take antibiotics, we can kill some beneficial bacteria resulting in digestive and other health problems. Science is trying to determine what is required for a healthy microbiome so that doctors can treat various issues that many times come from our poor choices regarding our health and diet. God designed a system that works, and we are just beginning to recognize that and learn how to take care of it.

— Roland Earnst © 2021

Tiny Living Things that Make Life Possible

Tiny Living Things that Make Life Possible

The natural world is incredibly complex, with a staggering number of things that we are not even aware of. Every cubic meter of air above a grassy field can contain more than 100,000 living things, many of which we can’t see. We seldom realize that it is these tiny living things that make life possible.

In 2008, Dr. Thomas Kunz at Boston University helped to establish a new scientific discipline called aeroecology. Dr. Kunz and his team used radar, telemetry, thermal imaging, and acoustic monitoring devices to study our lower atmosphere. Other scientists have continued studying aeroecology, which provides useful information in biology and such diverse areas as weather, wind turbines, conditions around airports affecting airplane safety, and disease control.


Aeroecology also involves controlling and maintaining insect populations. Insects are pollinators, and they are critical in a variety of food chains. Recent problems with bee die-offs have affected food production in many areas. Birds and bats help control airborne insects, and their survival is essential to maintain healthy conditions for the success of farming. A purple martin will eat about 20,000 insects yearly, which means this one species removes roughly 412 billion bugs from the atmosphere every year. Some birds stay in the air eating bugs for months at a time, like the alpine swifts of Europe and Africa. They can fly continuously for up to seven months while eating, drinking, and even sleeping.

All of this atmospheric life has a direct bearing on our bodies. We take in massive numbers of bacteria from the atmosphere. Studies by the germ-free research center at Notre Dame University have shown that microbes are critical for life. Researchers found that germ-free rabbits were unable to reproduce. Babies exposed to antibiotics during the first six months of their lives are prone to being overweight. A lack of microbes alters the serotonin levels in humans, affecting many areas of our health. Healthy humans have 1000 microbial species in their mouths and more than 10,000 species in their digestive systems.

The bottom line is that the life of a plant or animal is not just about the organism itself. It is also about the tiny living things that make life possible. The air and the soil are full of these supporting organisms. This indicates design by an Intelligence far beyond what humans can comprehend.

As we get more and better tools to look into the very small, we are astounded by their complexity and function. The Bible simply says God created life. We don’t see any detail, nor should we expect to. How would you explain bacteria to a man with no microscope? “We can know there is a God through the things he has made” (Romans 1:20). Our ability to understand the tiny living things that make life possible leaves us in awe of what God has done.

— John N. Clayton © 2020

Footnote: In 2011, Dr. Thomas Kunz was struck by a car and severely injured, ending his career. In 2020, Dr. Kunz, who introduced the science of aeroecology, died from an airborne disease—COVID-19. You can read more about his remarkable life HERE and HERE.