Mouth cells have some of the fastest turnover rates in the body. This is because oral cells must grow quickly enough to help the immune system and keep nearby organs free of bacteria. Good nutrition also supports the immune system and the body's ability to control oral bacteria so that they can digest or begin the digestion process without damaging gums, teeth or tissues. Foods that sit in our mouths for too long cause bacteria to grow, causing tooth and gum decay. All carbohydrates break down into simple sugars: glucose, fructose, maltose and lactose. However, it is the fermentable carbohydrates that degrade in the mouth. Foods containing fermentable carbohydrates, sugar or starch used by oral bacteria to produce acid cause tooth decay. This happens when oral bacteria, fond of sugary foods and highly refined carbohydrates, feed on simple sugars. The end product is acidic waste and biofilm, called plaque, a juxtaposition of bacteria and acid. This acid demineralizes tooth enamel, isolates dental plaque and irritates gum tissue. Saliva is an important agent against cavities because it removes certain sugars and reduces acidity in the mouth. It contains antibacterial compounds and enzymes (Amylase) which start the digestion process. These enzymes break down food between the teeth. Saliva contains butters that keep the pH of the mouth slightly alkaline (having a pH above 7). Without the pH being slightly alkaline, the early stage of digestion that occurs in the mouth would harbor many tooth-eating bacteria. However, the consistency of saliva impacts its effectiveness. Thinner saliva breaks up food and eliminates it quickly while thick saliva produces a more acidic layer producing paper...... middle of paper ......hy. Many of these healthy diet plans include healthy servings of fruit. This project determined how different fruits would affect oral bacterial growth and therefore be helpful to those dieters, who may be wondering "Which fruit is best for me?" » In terms of the health of their mouth as well as their body, this project would help them choose a fruit to eat in the middle of the day or before brushing. Pears, the fruit that causes the least bacterial growth, are also healthy for the body as they help reduce cholesterol and are an excellent source of dietary fiber and vitamin C. This project would also help parents and children. American children packing a lunch. Most children don't brush their teeth after lunch at school, so parents might pack a pear or banana for lunch instead of an apple or orange to prevent cavities or dental erosion..