Lemons are a good source of folate, potassium and Vitamin C. Folate is a water-soluble B vitamin known to prevent neural tube defects during pregnancy; it also may prevent cognitive decline, cancer, certain psychiatric illnesses and cardiovascular conditions. Potassium builds protein and muscle, maintains normal body growth and controls the electrical activity of the heart. Vitamin C is needed for the growth and repair of tissues throughout the body. As an anti-oxidant, it contains nutrients that block damage caused by free radicals, which play a role in cancer, heart disease and arthritis. Lemon water also plays a key role in cleansing your system. Water infused with lemon contains citric acid, which can clean out calcium stones and prevent calcium deposits from building up in arteries. These deposits promote cardiovascular disease. Lemon water provides the body with hydration, anti-oxidants and electrolytes. Lemon water serves as a tasty alternative to other, less healthy beverages. The Centers for Disease Control and Prevention say that while calories in drinks aren't "hidden," we don’t realize just how many calories beverages contribute to our daily intake. For example, in a 12-ounce serving:  apple juice has 192 calories, orange juice has 168 calories, lemonade has 168 calories and a sports drink has 99 calories. Healthy, lemon water has ZERO-- making it a great choice for a flavorful drink without all the added calories.