Though one or two colas a day may seem harmless, research suggests that cola contributes to osteoporosis.
Dr. Lawrence Raisz, director of the University of Connecticut Center for Osteoporosis says, "There is enough evidence that high consumption of soda and carbonated beverages is associated with somewhat lower bone mass in children, and that's a real concern and people should be aware of it."
Why exactly drinking soda, especially colas, is harmful to the bones is unclear. Experts agree that drinking cola affects bone density in several ways. It is possible that people who drink colas instead of nutritious beverages like milk or calcium-fortified juice may not get enough calcium and vitamin D in their diets.
Another reason could be related to the caffeine in colascaffeine has been linked to a higher risk of osteoporosis.
The third reason could be the presence of phosphosric acid in colas. Phosphoric acid can cause an imbalance in the body when the body seeks to neutralize the acid with calcium. If there isn't enough calcium in the diet, the body will take calcium from the bones to maintain the balance, thus leading to a depletion of calcium in the bones.
Dr. Primal Kaur, director of the Osteoporosis Center at Temple University Health Sciences Center in Philadelphia explains, "Phosphate is in milk, but milk also contains calcium and vitamin D. In soft drinks, there is just phosphoric acid and no calcium. Extra overzealous drinking may lead to a phosphoric acid imbalance, and if there's not enough calcium, the body goes to the bones to restore the balance."
Low levels of calcium can lead to osteoporosis, a disease where the bones become very thin and are at a high-fracture risk. According to the National Osteoporosis Foundation more than fifty percent of Americans, especially postmenopausal women, have an increased risk of developing osteoporosis.
A study involving more than 2,500 people with an average age of about 60 and researchers from Tufts University, found that cola consumption by women was associated with lower bone mineral density at three hip sites, irrespective of age, menopause, total calcium and vitamin D intake. They were women drinking an average of five carbonated drinks a week, four of which were colas.
Decaffeinated cola posed a lesser problem, but the findings were similar for diet soft drinks. The study could not establish a link between cola drinking and lower bone mass in men.
Acording to Dr. Kaur, "Moderation is really important. If you really like soft drinks, you don't need to take them out of your diet completely, but limit yourself to one or two glasses."
She added that people ought to make sure they are getting enough calcium and vitamin D to protect bone health. As Vitamin D needs varied by age, and where a person lived, it was imperative to check with a doctor to find out how much vitamin D a person should be consuming each day.
Kaur said that a person should take calcium supplement if he or she is not getting at least 1,000 to 1,200 milligrams of calcium from daily diet.
Dr. Lawrence Raisz observed that another important way to prevent osteoporosis is to exercise.
"The standard recommendation is a half an hour a day for adults and an hour a day for kids, but anything
is better than nothing," Dr. Raisz said. "Try to walk at least a half a mile a day, and engage in a weight-bearing exercise of some sort," he added.
The study was published recently in the American Journal of Clinical Nutrition