Digestive System

Intro to Health Occupations

Healthy Eating When You Have Digestion Problems

What you eat can contribute to digestive problems. Many people eat too much processed food and sugar, and not enough fiber, fruits, and vegetables. Poor eating habits, such as eating too quickly or skipping meals, can also be part of the problem. Many digestive problems can be prevented by eating a healthy, balanced diet.



  • Apples
  • Avocados
  • Bananas
  • Berries
  • Canned fruits (canned in fruit juice or water)
  • Cantaloupe
  • Grapes
  • Honeydew
  • Kiwi
  • Mango
  • Nectarines
  • Papaya
  • Peaches
  • Pears
  • Prunes
  • Watermelon


  • Asparagus
  • Beans (green, kidney, lima, navy, soybeans, yellow)
  • Beets
  • Broccoli
  • Brussels sprouts
  • Cabbage
  • Carrots
  • Cauliflower
  • Corn
  • Cucumbers
  • Kohlrabi
  • Leeks
  • Mushrooms
  • Onions
  • Peas
  • Peppers (green, red, or yellow)
  • Potatoes
  • Radishes
  • Rutabagas
  • Sauerkraut
  • Scallions
  • Spinach
  • Squash
  • Tomatoes
  • Turnips
  • Vegetable juices
  • Zucchini

How The Digestive System Works

The digestive system is made up of the alimentary canal (digestive tract) and the other abdominal organs that play a part in digestion, such as the liver and pancreas. The alimentary canal is the long tube of organs, including the esophagus, stomach, and intestines, that runs from the mouth to the anus. An adult's digestive tract is about 30 feet (about 9 meters) long.

Digestion begins in the mouth, well before food reaches the stomach. When we see, smell, taste, or even imagine a tasty meal, our salivary glands, which are located under the tongue and near the lower jaw, begin producing saliva. This flow of saliva is set in motion by a brain reflex that's triggered when we sense food or think about eating. In response to this sensory stimulation, the brain sends impulses through the nerves that control the salivary glands, telling them to prepare for a meal.

As the teeth tear and chop the food, saliva moistens it for easy swallowing. A digestive enzyme called amylase, which is found in saliva, starts to break down some of the carbohydrates (starches and sugars) in the food even before it leaves the mouth.

The Digestive System: CrashCourse Biology #28

Causes and Symptoms

Appendicitis is an inflammation of the appendix, a 3 1/2-inch-long tube of tissue that extends from the large intestine. No one is absolutely certain what the function of the appendix is. One thing we do know is that we can live without it, without any consequences.


Appendicitis occurs when the appendix becomes blocked, often by stool, a foreign body, or cancer. Blockage may also occur from infection, since the appendix swells in response to any infection in the body.

The common symptoms of appendicitis include:

  • Dull pain near the navel or the upper abdomen that becomes sharp as it moves to the lower right abdomen. This is usually the first sign.
  • Loss of appetite
  • Nausea or vomiting soon after abdominal pain begins
  • Abdominal swelling
  • Fever of 99-102 degrees Fahrenheit
  • Inability to pass gas

Connective Tissue


The inner layer of the digestive tract has specialized cells supported by an connective tissue layer called the lamina propria. The lamina propria contains blood vessels, nerves, lymphoid tissue and glands that support the mucosa. Depending on its function, the epithelium may be a simple single layer or multiple layers.


The submucosa surrounds the muscularis mucosa and consists of fat, fibrous connective tissue and larger vessels and nerves. At its outer margin there is a specialized nerve plexus called the submucosal plexus or Meissner plexus. This supplies the mucosa and submucosa.

~~~ Mucosa is a mucus-secreting membrane lining all bodily passages that are open to the air, as parts of the digestive and respiratory tracts.

Why Digestion Is Important

Digestion is important for breaking down food into nutrients, which the body uses for energy, growth, and cell repair. Food and drink must be changed into smaller molecules of nutrients before the blood absorbs them and carries them to cells throughout the body. The body breaks down nutrients from food and drink into carbohydrates, protein, fats, and vitamins.

Ways to Support Healthy Digestion

  • Chew thoroughly. Chewing is the physical process of breaking the food down into smaller pieces. Thorough chewing mixes food with saliva, which moistens the food. Chewing also tells the body to begin the digestion process, telling the stomach to be ready to make stomach acid, and telling the pancreas to prepare to release its contents into the small intestinal tract.
  • Ensure proper amounts of digestive factors. After chewing, the food's next stop is the stomach, where an adequate amount of stomach acid is located. Stomach acid is required for breakdown of proteins. Without stomach acid, not only is protein digestion ineffective, but also digestion of vitamin B12 is seriously affected. Vitamin B12 digestion and absorption requires that it be liberated from protein.


Nemours Foundation. "KidsHealth." Your Digestive System. The Nemours Foundation, 1995. Web. 12 Jan. 2014. <http://kidshealth.org/kid/htbw/digestive_system.html>.

Mateljan, George. "How Does Digestion Work and How Can I Improve Mine?" The World's Healthiest Foods. George Meteljan Foundation, 19 Jan. 2013. Web. 12 Jan. 2014. <http://www.whfoods.com/genpage.php?tname=faq>.

CrashCourse. "The Digestive System: CrashCourse Biology #28." YouTube. YouTube, 06 Aug. 2012. Web. 13 Jan. 2014. <http://www.youtube.com/watch?v=s06XzaKqELk>.

"National Digestive Diseases Information Clearinghouse (NDDIC)." Appendicitis. National Digestive Diseases Information Clearinghouse, n.d. Web. 12 Jan. 2014. <http://digestive.niddk.nih.gov/ddiseases/pubs/appendicitis/>.