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A new study suggests a ketogenic diet could improve mood and mental well-being in the general population. Natalia Mishina/Stocksy
  • The ketogenic diet has been recognized for its potential physical and mental health benefits.
  • A new study suggests that a ketogenic diet may also be associated with better mood and mental well-being in the general population.
  • For those new to keto, experts recommend starting this dietary pattern under the guidance of a nutrition professional, such as a dietitian.
  • Other dietary patterns, such as the Mediterranean or DASH diets, have more robust evidence for improving mental health.

The ketogenic diet is characterized by high fat, low carbohydrate, and moderate protein intake. This diet has been acknowledged for its potential metabolic and psychological benefits.

A recent pilot study from Stanford Medicine also reported improved symptoms in patients with severe mental illness after a 4-month ketogenic regimen and standard treatment.

Building on these findings, a new study investigated how the keto diet affects different aspects of mental health in the general global population.

The findings, published in Nutrition, suggest that following a ketogenic diet may be linked with better mental and emotional health in the general population, with benefits increasing over time.

Researchers at Northumbria University in Newcastle-upon-Tyne, England, aimed to find out how the ketogenic diet could affect various aspects of mental health, including:

  • mood (calmness, contentedness, alertness)
  • cognitive and emotional stress
  • depression and anxiety symptoms
  • feelings of loneliness

Researchers compared the self-reported mental health outcomes of individuals on a ketogenic diet with those on other diets, using data from two online surveys.

This study authors recruited participants via social media for two cohorts:

  • 2021 cohort — 147 participants
  • 2022 cohort — 276 participants

All participants were 18 or older and free from clinically diagnosed mood, anxiety, neurodevelopmental, and neurodegenerative disorders.

The first cohort responded to surveys that included Bond-Lader visual analog mood scales and the Perceived Stress Scale, while the second cohort completed surveys featuring the Depression Anxiety Stress Scale and the revised UCLA Loneliness Scale.

Both cohorts were asked the same demographic, socioeconomic, and health-related questions and dietary habits were collected using a one-week, 45-item food frequency questionnaire.

To identify ketogenic dietary patterns within the cohorts, foods were categorized based on compatibility with the ketogenic diet:

  • Ketogenic-friendly: meats, poultry, fish and seafood, certain dairy products, eggs, tofu, tempeh, nuts, most vegetables, tea, and coffee.
  • Ketogenic-acceptable: fruit (fresh or frozen), most fruit juice, squash, low-calorie or diet beverages, certain meat substitutes, cottage cheese, and dairy or non-dairy spreads.
  • Not ketogenic-friendly: fruits canned in syrup or dried, grains, potatoes, beans and pulses, sugary snacks and drinks, chips and savory snacks, low fat and flavored yogurts, and breaded or battered meats, poultry, and fish.

The surveys also asked participants whether they were following a ketogenic diet, their main reason for following it, if they measured their ketone levels, and if so, what their last reading was.

Individuals reporting a ketogenic diet must have adhered to it for at least one week to be considered ketogenic diet followers in the final analysis. Those who said they weren’t following a ketogenic diet were simply grouped as “other diets.”

Survey results identified 220 participants adhering to a ketogenic diet across the two cohorts. Their primary motivations for adopting a ketogenic diet were overall health and weight loss.

Notably, over 70% of participants did not monitor their ketone levels, leaving their actual ketosis status largely unconfirmed.

In the first cohort, the average body mass index (BMI) was classified as overweight among both ketogenic diet followers and those following other diets.

However, ketogenic diet followers had a significantly higher BMI than those on other diets, were older, and were more likely to have high blood pressure.

The second cohort showed similar age patterns but no significant difference in blood pressure or BMI between diet groups.

Both cohorts reported better psychological well-being among ketogenic diet followers, including:

  • superior mood states (calmness, contentedness, alertness)
  • reduced anxiety and depression
  • fewer feelings of stress and loneliness

However, reported loneliness was not statistically significant after adjusting for group disparities.

These psychological benefits appeared regardless of ketone levels, suggesting that sustained dietary habits might contribute to mental well-being regardless of metabolic changes.

Participants followed the ketogenic diet for an average of 24 months in the first cohort and 44 months in the second.

The study authors noted that, in contrast to previous research, longer adherence to the ketogenic diet correlated with better mood.

Medical News Today spoke with Jasmine Sawhne, MD, a board certified psychiatrist not involved in the study, who explained how a ketogenic diet might improve psychological well-being.

She noted that the diet could increase gamma-aminobutyric acid (GABA) levels, promoting calmness and relaxation similar to the effects of benzodiazepines — medications used to treat various conditions, including anxiety.

The ketogenic diet may also influence neurotransmitters like dopamine and serotonin, which regulate mood, and the gut microbiome, which affects behavior and stress response, Sawhne explained.

Still, she emphasized, “future studies could benefit from incorporating biological markers to complement self-reported data, especially regarding neurotransmitter levels, stress hormones like cortisol, and gut microbiome composition.”

Kiran Campbell, a registered dietitian nutritionist with a background in psychology, not involved in the study, agreed that further research is needed into the long-term mental health effects of a ketogenic diet.

She pointed out that “some studies show no long-term benefits on mood or cognition,” contrasting with the current study’s findings of increased benefits over time.

Additionally, research on cortisol levels during a ketogenic diet remains inconclusive, she noted.

Before attempting the ketogenic diet, Sawhne underlined the importance of consulting healthcare providers, “especially for those with complex health conditions or considering major dietary changes.”

“While this diet does show evidence of benefits for mental health, we are not yet at a point to safely recommend a ketogenic diet for mood disorders or to improve mental health in the general population,” said Campbell.

Instead, a balanced, whole-food, plant-forward diet is recommended. Both Sawhne and Campbell suggest Mediterranean or DASH diets, which have more documented mental health benefits and fewer associated risks.

For individuals with mental health conditions, “[these diets] may be recommended in conjunction with traditional psychiatric treatments,” said Sawhne.

Limiting certain ultra-processed foods and consuming healthy carbohydrates and omega-3 fatty acids can further benefit mood and support mental health, Campbell concluded.