Sugar Consumption Is Linked to a Higher Risk of Depression, New Study Finds

Eating a lot of sugar has repeatedly been tied to a slew of serious health conditions like obesity and heart disease. Now, there’s another one to add to the list: depression. 

A new study published in the Journal of Translational Medicine found that people with a sweet tooth were more likely to have depression than people who preferred less sweet foods. The study analyzed data from nearly 182,000 people and sorted them into three groups: Health-conscious, who prefer fruits and vegetables over animal-based foods and sweets; omnivores, who like most foods, including meat, fish, some vegetables, and sweets; and people with a sweet tooth, who enjoy having a lot of sugary foods and drinks, with fewer fruits and vegetables. 

The researchers calculated the risks of developing chronic diseases and mental health conditions for each participant, and found that people in the health-conscious group had a 14% lower risk of heart failure and a 31% lower risk of chronic kidney disease compared to the other groups. But people in the sweet tooth group had a 27% higher risk of depression, a 22% greater risk of stroke, and a 15% higher risk of diabetes, than the other groups. 

The study is raising a lot of questions about the link between sugar and depression, including the impact having a sweet tooth may have on your mental health. Here’s what we know.

Why is sugar linked with a higher risk of depression?

It’s important to get this out of the way upfront: The study found a link between people who prefer sweet foods and depression, but didn’t find that having a sweet tooth actually causes depression. 

“We cannot definitively answer if sugar consumption causes depression,” says study co-author Nophar Geifman, PhD, professor of health and biomedical informatics at University of Surrey. 

But this isn’t the first time sugar has been linked to depression. “There has been research that shows a direct relationship between sugar intake and increased levels of depression, with a suggestion that increased sugar intake impacts mechanisms of the brain directly,” says Hillary Ammon, PsyD, a clinical psychologist at the Center for Anxiety & Women’s Emotional Wellness. 

Sugar can also increase the chance of developing certain health issues, like weight gain or diabetes, she points out. “We know that individuals struggling with weight gain or diabetes may be at greater risk for leading a sedentary lifestyle and increased levels of depression, as well,” Ammon says. 

Diets high in sugar can increase bodily inflammation, which can increase the risk of depression, says Gail Saltz, MD, associate professor of psychiatry at the NY Presbyterian Hospital Weill-Cornell School of Medicine. Sugar may also interfere with the bacteria in your gut, she says, adding, “there is a gut-brain connection that could explain increased depression.” 

A high-sugar diet may also increase production of the stress hormone cortisol in the body, which could raise the risk of depression, Saltz says. 

“Lastly, sugar is comforting,” Ammon says. “Many people struggling with tough emotions may eat sugary products to cope, likely worsening the cycle of depression and the dependency on sugar to cope.” 

How much sugar is OK?

The Dietary Guidelines for Americans recommends that people over the age of 2 have no more than 10% of their daily calories from added sugars. (Added sugars are sugars that are added during the processing of foods.) That means people following a 2,000 calorie diet should have no more than 200 calories a day from added sugars. 

Geifman says it’s hard to say how much sugar will tip you into a higher risk of developing depression. “Enjoying sweets in moderation is unlikely to have immediate negative effects,” she says. “However, consistent high sugar intake, especially from hidden sugars in packaged foods, could potentially build up health risk over time.”

One study published earlier this year found that for every additional eight tablespoons of sugar a person eats, there is a higher risk of depression. But again, it doesn’t prove that having sugar causes depression. 

“It’s important to look at these findings in the context of overall dietary patterns and lifestyle choices, rather than focusing on a single food item/group,” Geifman says. Saltz agrees, noting that the link between depression and sugar, “doesn’t happen with a one-and-done consumption.”

What does this mean for people who already have depression?

Experts say that it’s important for everyone to be aware of their sugar consumption. But, if you have depression, it’s a good idea to try to limit how much you have. “A super high refined sugar diet makes it harder to treat your depression,” Saltz says. “So, while a low-sugar diet won’t treat depression, being mindfully moderate in sugar intake can make it less hard to treat your depression.”

Ammon recommends having sugar in moderation but acknowledges that it can be difficult. “If you are noticing you are dependent on sweets, it may be beneficial to take a break from refined sugars and see how you feel in the weeks to come,” she says. “Often, the less you eat something for a sustained period of time, the less you crave it.”