Dental caries and chronic periodontitis are by far the most common oral diseases in the elderly, and these conditions are related to diet. Frequent and high intake of sugary drinks and other foods rich in fermentable carbohydrates is known to increase the risk of caries, while fluoride decreases caries risk. Dairy consumption appears to be associated with lower caries levels. Obesity increases the risk of periodontitis as the adipose tissue serve as a reservoir for inflammatory cytokines. Nutrients such as vitamin D, vitamin C, carotenoids and omega 3 fatty acids could also affect periodontitis risk. Intake of calcium, vitamin D, and dairy products have been associated in a few studies with reduced risk of periodontitis. Furthermore, intake of whole grains may also reduce the risk of periodontitis. Nutritional factors also impact risk of oral cancer. A diet high in fruits and vegetables, more so if raw and diverse, protects against oral pre-cancer and cancer. Several nutrients found in vegetables and fruits including vitamins A, B complex, C, E and other components such as carotenoids, glutathione, lycopene, lutein and flavonoids, show an inverse association with oral cancer. Furthermore, a dietary pattern high in fruits, vegetables, other fiber-rich foods, and fish are associated with a reduced cancer risk while saturated fat, processed and refined foods, and fast foods are associated with an increased risk. On the other hand, oral health also affects nutrition, as edentulous individuals are more likely to eat a diet that may be detrimental to health (fewer fruits and vegetables and less fiber, calcium, iron, pantothenic acid, vitamins C and E, carotene and polyunsaturated fat, but more cholesterol, saturated fat, and calories). In addition, those with oral cancer experience numerous complications such as difficulty for eating and swallowing, as side effects of radiation. A healthy dentition is important for maintaining healthy nutrition status and vice versa, as oral conditions both affect and are affected by nutrition.