Nutrition Science; Why what we know about what we eat matters

Title Layout Nutrition Science Digital Study Guide 1 Why what we know about what we eat matters? “If you’re not a nutrition expert, you probably think you’re doing yourself a favor by cooking with healthy coconut oil and avoiding slathering's of fattening peanut butter — but actual nutrition experts would disagree (Downing, 2017, p. 1)”. Mechanism Organs Process flow Utilization Waste and excess Optimization Energy Lipids Carbohydrates Vitamins and Nutrients Be aware Be responsible Continuous learning 2 How is food processed? What does our body do with it What is good or bad? What should we do? The Digestive System The mouth is the beginning of the digestive tract; and, in fact, digestion starts here when taking the first bite of food. Chewing breaks the food into pieces that are more easily digested, while saliva mixes with food to begin the process of breaking it down into a form your body can absorb and use. Located in your throat near your trachea (windpipe), the esophagus receives food from your mouth when you swallow. By means of a series of muscular contractions called peristalsis, the esophagus delivers food to your stomach. The stomach is a hollow organ, or "container," that holds food while it is being mixed with enzymes that continue the process of breaking down food into a usable form. Cells in the lining of the stomach secrete a strong acid and powerful enzymes that are responsible for the breakdown process. When the contents of the stomach are sufficiently processed, they are released into the small intestine. Made up of three segments - the duodenum, jejunum, and ileum - the small intestine is a 22-foot long muscular tube that breaks down food using enzymes released by the pancreas and bile from the liver. Peristalsis also is at work in this organ, moving food through and mixing it with digestive secretions from the pancreas and liver. The duodenum is largely responsible for the continuous breaking-down process, with the jejunum and ileum mainly responsible for absorption of nutrients into the bloodstream. The pancreas secretes digestive enzymes into the duodenum, the first segment of the small intestine. These enzymes break down protein, fats, and carbohydrates. The pancreas also makes insulin, secreting it directly into the bloodstream. Insulin is the chief hormone for metabolizing sugar The liver has multiple functions, but its main function within the digestive system is to process the nutrients absorbed from the small intestine. Bile from the liver secreted into the small intestine also plays an important role in digesting fat. In addition, the liver is the body's chemical "factory." It takes the raw materials absorbed by the intestine and makes all the various chemicals the body needs to function. The liver also detoxifies potentially harmful chemicals. It breaks down and secretes many drugs. The gallbladder stores and concentrates bile, and then releases it into the duodenum to help absorb and digest fats. The colon is a 6-foot long muscular tube that connects the small intestine to the rectum. The