It’s no news flash that soda — diet or otherwise — is bad for health; even those who happily indulge in a can-a-day (or more) habit can rattle off at least two or three negative effects of soda consumption. But when it comes to the effects of soft drink consumption on the human body, the total picture is downright scary.
With high levels of sugar, acids, preservatives and other harmful ingredients, soda causes more damage to the body than just expanding the waistline. From stroke to kidney stones to dementia, here’s a look at what can happen to the body long-term for those who regularly drink soda.
Consuming excessive amounts of sugar reduces the production of the brain chemical called brain-derived neurotrophic factor, or BDNF. “Without BDNF, our brains can’t form new memories and we can’t learn (or remember) much of anything,” according to an article in Forbes.
Another study found that low BDNF levels are linked to depression and dementia. What’s more, when BDNF levels are reduced, the body begins to become resistant to insulin, which kicks off a cascade of other health problems.
But there’s a more immediate problem: Chronic sugar consumption dulls the brain’s mechanism for knowing when to stop eating, making you more likely to binge — and snack on sugar.
Sugar is not the only harmful substance in soda that affects dental health. A 2006 study found that soda is nearly as harmful for your teeth as battery acid. That’s because soda actually contains acid (most commonly citric and/or phosphoric), which corrodes tooth enamel. Diet sodas are even more harmful, as they're more acidic than regular sodas.
What does this mean for your teeth? According to the Colgate Oral and Dental Health Resource Center: “Acids and acidic sugar byproducts in soft drinks soften tooth enamel, contributing to the formation of cavities. In extreme cases, softer enamel combined with improper brushing, grinding of the teeth or other conditions can lead to tooth loss.”
Recent research has shown a correlation between soda consumption and heart disease. Most recently, a Harvard study found that one daily 12-ounce serving of regular soda was linked to a nearly 20 percent increase in the risk of cardiovascular disease.
Some researchers say the blame can be placed on high fructose corn syrup, which has been linked to an increased risk of metabolic syndrome, a condition associated with an elevated heart disease risk.
However, others say diet sodas with artificial sweeteners are much worse on the heart. One such study says that those who had a daily diet soda habit had a 61 percent increased risk of “cardiovascular event,” including heart attack and stroke, than those who drank no soda.
Drinking too much soda can increase the risk for developing asthma or chronic obstructive pulmonary disorder, according to a recent study — and the more soda a person consumes, the greater the risk of developing these diseases. Sodium benzoate, a preservative in soda, may be directly affecting the lungs: It increases the amount of sodium in the body while reducing the availability of potassium, causing asthma as well as eczema.
Soda consumption has been linked to osteoporosis and bone density loss. While some suggest it's because those who regularly consume soft drinks — especially in large amounts — are not leaving enough room in their diets for healthier drinks, other studies say phosphoric acid may be to blame.
“Phosphorus itself is an important bone mineral, but if you're getting a disproportionate amount of phosphorus compared to the amount of calcium you're getting, that could lead to bone loss,” according to WebMD.
Caffeine may also be the culprit, as it is known to interfere with calcium absorption.
The high levels of phosphoric acid particularly found in colas have been linked to kidney stones and other renal problems, but diet cola is most likely to have a negative effect on kidney function. In fact, diet cola is associated with a two-fold increased risk. According to a Harvard study, kidney function started declining when subjects drank more than two sodas a day.
For those with digestive issues, consuming soda will only add to their troubles. The carbonation in soft drinks can irritate the digestive system, particularly in those who have irritable bowel syndrome. Carbonation can cause a buildup of gas, leading to bloating, cramping and pain. The caffeine in soda can also increase stomach acid production, worsen episodes of diarrhea, and contribute to constipation. In addition, the sweeteners used in soft drinks can worsen IBS symptoms due to their laxative effects.
Drinking just one soda a day equates to consuming 39 pounds of sugar per year — one of the main reasons soda consumption is strongly linked to obesity. A recent study found that sugar-sweetened beverages are linked to more than 180,000 obesity-related deaths each year, which means that about one in every 100 deaths from obesity-related diseases is caused by drinking sugary beverages. An additional study concluded that regularly consuming drinks high in sugar interacts with the genes that affect weight, dramatically increasing a person’s risk for obesity.