Medical Studies Say Diet Sodas are Linked to Depression and are as Unhealthy as Sugar-Heavy Regular Sodas

Joel Eisenberg

Though regular soda is widely considered unhealthful due to its high-sugar content, the consensus is the diet variety is not only linked to depression but also a possible cause.
Coke VarietiesiStock

Author’s Note

This article is free of opinion and bias, and is based solely on science and accredited media reports. No medical advice is offered herein on the part of the author. All listed theories and facts within this article are fully-attributed to several medical experts, scientists, and media outlets, including,, Joe Leech (MS), Rachael Link (MS, RD), Alissa Palladino (MS, RDN, LD, CPT),, Salynn Boyles, Laura J. Martin (MD), American Academy of Neurology, Jennifer Robinson (MD), Wikipedia,, and Naveed Saleh (MD, MS).

For further perspective, I am a former mental health professional with training in Psychology. Though I left the field to become a full-time writer, I have continued my studies in the mental health realm.


One week ago, the following article was published on NewsBreak: “Medical Studies Disclose Dangers of Diet Soda on Physical and Mental Health.” I wrote that piece, and among early comments I received were several alluding to medical warnings about regular soda. I was subsequently asked by some who commented if I could pen an article about those dangers, while others requested a deeper dive on the diet varieties.

I came to the conclusion that readers interested in the topic would best be served by my offering a health-related comparison of the two soda varieties, and so this article came to be.

Whereas the likelihood of finding medical professionals willing to laud the health benefits of any soda is slim, many experts who work within the medical field regularly debate which soda variety is the least healthy.

As studies have shown diet soda has more of a negative impact on one’s mental health, while regular soda may be more deleterious to one’s physical health, there is no single qualification to determine which is worse for the consumer overall. Experts advise soda in general should be avoided… but is that possible?

If we judge by current sales, which last year according to notably increased from the prior year, expecting consumers to give up one of its most-favored pastimes remains an exercise in futility.

Diet vs. Regular

According to, there are many reasons why regular soda is considered unhealthy. See here for "13 Ways Sugary Soda is Bad for You."

From the article, written by Joe Leech, MS: When consumed in excess, added sugar can adversely affect your health. However, some sources of sugar are worse than others — and sugary drinks are by far the worst. This primarily applies to sugary soda but also to fruit juices, highly sweetened coffees, and other sources of liquid sugar.

Among those health dangers include the potential for insulin resistance, sugar stored as fat in the liver, and the potential for weight gain.

Diet sodas may not be as often targeted for physical dangers although there too the potential is certainly present. See here for another article, this one written by Rachael Link, MS, RD, medically reviewed by Alissa Palladino, MS, RDN, LD, CPT, and entitled "8 Potential Side Effects of Consuming too Much Diet Soda."

Among those potential side effects listed is a decrease in bone density, an erosion of tooth enamel, and heart issues relative to observational findings.

From the article, which also notes more research is needed before a definitive conclusion can be made in this regard: One study in 59,614 women showed that drinking at least 2 diet drinks per day was associated with a higher risk of heart problems and dying from heart disease over a 9-year period. Other older studies have found that both diet and regular soda intake could be linked to an increased risk of stroke. Plus, diet soda has been tied to a higher risk of metabolic syndrome, which is a group of conditions that can increase your risk of heart disease, stroke, and type 2 diabetes.

An older article (2013) from entitled "Sweetened Drinks linked to Depression Risk," written by Salynn Boyles and medically reviewed by Laura J. Martin, MD, illustrates early debate about soda in general being a culprit for depression.

From the article: Researchers say the findings suggest that cutting down on sweetened drinks or replacing them entirely with non-sweetened beverages may help lower depression risk. But an expert who reviewed the findings says it failed to convince him that drinking sweetened beverages raises depression risk. “There is much more evidence that people who are depressed crave sweet things than there is to suggest that sweetened beverages cause depression,” says neurologist Kenneth M. Heilman, MD.

The study referenced was presented that year at the 65th annual meeting of the American Academy of Neurology in San Diego.

In the ensuing years, medical sentiment has largely turned. The general consensus is diet soda is the greater culprit for mental issues as the sugar-sweetened regular iterations are more likely to result in a sugar crash that can mimic signs of depression than any defined mental health issue. See here for another WebMD article, this one from 2021 and solely credited as being medically reviewed by Jennifer Robinson, MD, entitled "Foods to Avoid if You Have Anxiety or Depression."

From the article: No sugar, so no problem, right? Not exactly. You may not have the energy crash that comes with having too much sugar, but diet soda may make you depressed. In fact, it could make you feel more down than its sugary cousin would. Too much of the caffeine that many sodas have can be bad for anxiety, too.

According to Wikipedia, the primary sweeteners placed in diet soda to replace sugar, all of which are said to be potentially risky for one's mental health, include aspartame, sucralose, cyclamates (outside the US), acesulfame potassium ("Ace K"), and stevia. These artificial sweeteners have also been considered cancer links, which is discussed in the Wikipedia entry.

Finally, published "5 Reasons to Avoid Diet Drinks at All Costs" by Naveed Saleh, MD, MS, which distinguishes the impact of diet soda among those who already suffer from depression-related issues, and those who do not: Per the research, the effects of aspartame on mood are mixed but nonetheless concerning. In one early crossover trial, investigators randomized 40 patients with unipolar depression to receive either aspartame 30 mg/kg/day or placebo for 7 days. Only 13 patients completed the study, with the study truncated by the Institutional Review Board due to the severity of depression in those taking aspartame. “Despite the small [sample size], there was a significant difference between aspartame and placebo in number and severity of symptoms for patients with a history of depression, whereas for individuals without such a history there was not. We conclude that individuals with mood disorders are particularly sensitive to this artificial sweetener and its use in this population should be discouraged,” wrote the authors.

That article can be found here.


Taking older and newer studies as linked above into consideration, soda is generally unhealthy regardless of diet or regular.

I don't believe any one of us is surprised by this outcome.

Thank you for reading.

Comments / 128

Published by

I am an award-winning author, screenwriter for film and television, and producer. My mission on News Break is to share socially important perspectives on both culture and pop-culture. Member of PEN America, and the WGA.

Northridge, CA

More from Joel Eisenberg

Comments / 0