In the U.S., an estimated 9.4 percent of the population has diabetes. It is the seventh leading cause of mortality in the country.
While type 1 diabetes is not preventable, an individual can take steps to reduce the more common type 2 by moderating sugar intake.
In this article, we examine the effects of soda on diabetes risk and how cutting it out can help prevent the development of the common and life-threatening disease.
Soda and diabetes
Research is yet to confirm the exact link between soda and diabetes.
Soda can also reduce the ability of people who already have diabetes to control blood glucose, according to this research from 2017.
According to a study published in 2010, the risk of developing diabetes is 26 percent higher for people who consume one or more sugary drinks every day.
Even switching to artificially sweetened or 'diet' soda containing sugar alternatives may not reduce the risk of diabetes. While research on these has reached more varied conclusions, this 2018 investigation suggests that artificially sweetened beverage consumption cannot be ruled out as a risk factor for diabetes.
Insulin resistance is central to the development of type 2 diabetes. It occurs when the cells become used to an excess of sugar in the bloodstream and do not absorb glucose as effectively, responding less to insulin. Insulin is the hormone that unlocks cells, allows glucose to enter.
This 2016 study found that sugar-sweetened beverages contribute to the progression of insulin resistance and prediabetes, the stage before full diabetes.
Some studies, controversially, found no association between added sugars and diabetes, such as this review from 2016.
However, the study authors list their conflicts of interest at the end of the article, advising funding from an array of food and drink manufacturers who add vast amounts of sugar to products, including The Coca Cola Company and PepsiCo, bringing into question the reliability of the evidence.
How do sweetened drinks lead to diabetes?
Drinking too many sweetened drinks means that the body stores excess energy in the form of fat, so, drinking too much soda can play a part in the development of overweight and obesity.
Research has shown that being overweight or obese is a risk factor for type 2 diabetes and other conditions.
A review of relevant studies, compiled in 2015, confirmed the relationship between diabetes and beverages sweetened with sugar despite the exact biological mechanisms remaining unclear.
One study, published by The American Journal of Clinical Nutrition in 2010, investigated relationships between the diet and health of 91,249 female nurses over 8 years. They found a link between a diet with a high glycemic index (GI), or quickly digested foods and drinks that cause a spike in blood sugar, and type 2 diabetes.
The risk for diabetes was high even after taking into account other known risks and dietary factors involved in diabetes. In fact, the diabetes risk associated with a high energy intake was greater than that of consuming unhealthy fats.
The authors explained the following process through which high sugar intake could lead to diabetes:
- Higher blood glucose concentrations from a high load of quick-digesting carbs mean more demand for insulin.
- Higher demand for insulin in the long-term wears out the pancreas. This can result in glucose intolerance from the cells.
- High-GI diets may, therefore, directly increase insulin resistance.
As soda has an extremely high GI, it may well contribute to this process.
The review also supports the suggestion that high sugar intake adds to obesity by increasing the total energy consumed.
In other words, as sugary beverages add to the overall daily intake of calories, the increase in calories likely leads to an increase in weight.
The paper also investigated the idea of sugar-sweetened drinks more directly causing type 2 diabetes. They concluded that research in this area had not yet been able to rule out other factors, such as obesity, and that further research is needed.
A case-cohort study from 2013 investigating the relationship between sugar-sweetened drinks and diabetes compared data about the soda consumption habits of 11,684 people with type 2 diabetes to those of 15,374 people who did not have diabetes.
The team found that people who consumed one or more sugar-sweetened drinks every day had a higher risk for diabetes than those who drank less than one a month. Even when energy intake and body mass index (BMI) were accounted for, the high soda drinkers still had a higher risk for type 2 diabetes.
The authors of the report speculated how sugar-sweetened drinks could potentially cause type 2 diabetes, but, as with other researchers, could offer no firm conclusions. Their study could not prove a direct causal link between soda and diabetes risk, just a correlation between the two.
The authors did, however, suggest that the link could be due to "an effect on weight gain," as well as the "glycemic effects" of sugar-sweetened drinks "inducing rapid spikes in glucose and insulin and causing insulin resistance."
Is diet soda healthier?
Diet soda may not be any better for people with diabetes.
Artificially sweetened sodas are controversial.
While some studies, such as these findings from 2016, found that sugar-sweetened beverages increased the risk of diabetes whereas diet soda did not.
Some people see diet, low-sugar, or alternatively sweetened soda as a less damaging option.
Another study followed the soda consumption habits of thousands of people and compared those who developed diabetes with those who did not. They did find a link between artificially sweetened drinks and diabetes.
However, further analysis showed that those with higher diet soda intake were more likely to already have, or be at higher risk for, diabetes. The effect also disappeared from the analysis when their higher BMI was taken into account.
Not all researchers are convinced by diet soda, though. One reviewer, writing in 2013, said "frequent consumption of high-intensity sweeteners" might have an effect opposite to that desired. It may lead to metabolic issues that can contribute to heart disease, type 2 diabetes, and high blood pressure.
A potentially harmful effect of artificially sweetened beverages on glycemic control for people who already have diabetes is that the artificial sweeteners are roughly 200 times sweeter than sugar. This extra sweetness then tricks the brain into reducing blood glucose levels, running the risk of hypoglycemia.
The author, Susan Swithers, writing while at the Ingestive Behavior Research Center of Purdue University, West Lafayette, IN, concluded:
"Current findings suggest that caution about the overall sweetening of the diet is warranted, regardless of whether the sweetener provides energy directly or not."
Overall, moderation is key. Too much of any food or drink is likely to have adverse health effects, especially if it contains high levels of sugar.
Sugary beverages and sodas contribute to diabetes risk, as well as issues controlling blood sugar in people who already have diabetes.
The body digests the sugars from soda quickly. This contributes to insulin resistance and causes rapid spikes in blood sugar.
The effect of artificially sweetened beverages on diabetes is less clear. While some studies claim that it has less or no impact on the risk of developing diabetes, others suggest that it affects the mechanisms that lead to diabetes in different ways.
Consume low amounts of soda, and be sure to involve physical activity in your daily routine.
What can I replace soda with in the diet to reduce the risk of diabetes?
Replace sodas in the diet with more healthful options such as green tea or no sugar added coconut water, or spruce up your water with a splash of juice or fresh-cut fruit or vegetables. Some ideas are strawberries, lemon, lime, grapefruit, cucumbers, pineapple, oranges, watermelon or mint.Katherine Marengo LDN, RD Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.