Intestinal villi Intestinal villi (singular: villus) are tiny, finger-like projections that come out from the wall of the small intestine and have additional extensions called microvilli (singular: microvillus) which protrude from epithelial cells lining villi. They increase the absorptive area and the surface area of the intestinal wall. It is important that the food is absorbed at a considerably fast rate so as to allow more food to be absorbed. (If the process is too slow, the concentration of the blood in the blood vessels and the food will be equal, thus, diffusion will not occur.) Digested nutrients (including sugars and amino acids) pass into the villi through diffusion. Circulating blood then carries these nutrients away.

Intestinal villi Blood capillaries absorb amino acids, glucose, vitamins and minerals into the blood stream The lacteals absorb fatty acids and glycerol into the lymphatic system

NUTRITIONAL DISEASES

Ulcers open sores on the wall of the stomach or small intestine 1/10 people get an ulcer the cause? most ulcers are caused by a specific bacteria many have the bacteria, but not all get ulcers maybe due to the level of acids in the stomach of those with the bacteria it is thought that the bacteria weakens the stomach mucus coating

Ulcers  symptoms  abdominal pain  nausea  frequent burping  weight loss  vomit or stools may have blood in severe cases  tests  medical history and exam  endoscopy  upper GI series

Ulcers  increased risk with alcohol and cigarettes  alcohol wears down the stomach lining  nicotine increases stomach acid  treatment  meds to kill the bacteria  meds to reduce stomach acid  changes in lifestyle

CONISTIPATION Constipation or irregularity, is a condition of the digestive system in which a person (or animal) experiences hard feces that are difficult to expel. This usually happens because the colon absorbs too much water from the food. If the food moves through the gastro-intestinal tract too slowly, the colon may absorb too much water, resulting in feces that are dry and hard.

DIARRHEA In medicine, diarrhea is frequent loose or liquid bowel movements. The word "diarrhea" with its odd spelling is a near steal from the Greek "diarrhoia" meaning "a flowing through." Acute diarrhea is a common cause of death in developing countries and the second most common cause of infant deaths worldwide.

APPENDICITIS Appendicitis is a condition characterized by inflammation of the appendix. All cases require removal of the inflamed appendix. Untreated, mortality is high, mainly because of infection and shock.

GALLSTONES Gallstones are bodies formed within the body by crystallization of normal or abnormal bile. Gallstones can occur in the gallbladder and in the bile duct. Obstruction of the bile duct (or duct system) can cause jaundice or pancreatitis.

OBESITY 1/3 of Americans are obese 2/3 of Americans are overweight more men are overweight – more women are obese 300,000 preventable deaths each year in the US strong familial component

OBESITY increased risk of high blood pressure, diabetes, heart disease, stroke, gall bladder disease, cancer (breast, prostate, colon) why the increase of obesity? decreased physical activity accessible cheap, high calorie, fast food processes and pre-packaged foods

ANOREXIA NERVOSA  teen girls obsessed with thinness  fat body image no matter how thin  starve themselves and exercise constantly  often perfectionists – has a strong emotional (physiological) component

ANOREXIA NERVOSA related problems stopped menstrual period dry skin hair loss extreme weight loss feeling cold often sick can be at risk for death from starvation

BULIMIA  similar to anorexia nervosa, but not as sever a weight loss  has binge and purge behavior – may use diuretics and laxatives