According to the Beverage Marketing Corporation, more than 14 billion gallons of carbonated soft drinks were purchased for consumption in 2008 alone. When consumed in moderation, the occasional soft drink is typically not going to do much harm, but when consumed on a regular daily basis, you put yourself at risk for developing a host of different health problems.

Tooth Decay

Most soft drinks are loaded with sugar.  In fact, the average 12-oz. can of soda can contain as much as 46 grams of sugar. To reach your stomach, soda comes into contact with your teeth. Sugar is a prime fuel source for the bacteria that form layers of harmful plaque on teeth. This dental plaque plays a large role in tooth decay.

Diabetes

The sugar content of soft drinks can also contribute to the development of type 2 diabetes. Consistently consuming more sugar than your body can normally handle can contribute to insulin resistance in your body. As your body becomes insulin resistant, your cells are unable to remove sugar (in the form of glucose) from your bloodstream, resulting in unhealthy high glucose levels in the blood. These high glucose levels can cause damage to your body over time.

Obesity

One of the most dangerous health factors related to consuming soft drinks is the increased risk for obesity. Being obese puts you at a higher risk for developing many diseases and conditions including heart disease, diabetes and even some forms of cancer. The average can of soda contains about 150 calories. If you were to drink only one soda a day for a year, you would consume an additional 54,750 calories in your diet. Unfortunately, many people consume much more than one soda a day. By cutting even one can of soda from your daily diet you can lose as much as 15 pounds in a year (3,500 calories is equal to one pound).

Calcium Absorption

Many soft drinks also contain phosphoric acid. According to the American Dental Association, this phosphorous content may affect calcium absorption in the body, which can increase your risks of developing osteoporosis. Younger children that are still growing can also be put at risk, as calcium is needed to grow healthy bones during development. 

 It is the best season for cold soft drinks, 

 but be careful not to drink too much!!

【Reference】

http://www.livestrong.com/article/87691-health-problems-caused-soft-drinks/