New Stanford Study: Eating This Many Carbs May Optimize Your Brain

Updated: May 19, 2024

New research from expert doctors suggests a link between "metabolic abnormality" and psychiatric disorders...with carbohydrate consumption as a glaring common denominator.

While low-carb diets have long been touted for weight loss, reducing inflammation and improving blood sugar readings, new research suggests that lessening carb consumption might also stabilize the mood and mental health.

Maybe you’ve heard of “grain brain,” which is the phrase neurologist and author David Perlmutter, MD, coined in his 2013 book by that title. “Grain brain” is said to describe the effects that refined flours and starchy foods can have on the brain, as Dr. Perlmutter asserts that “carbs are destroying your brain” by contributing to conditions such as dementia, depression, anxiety, ADHD, anxiety, chronic headaches, and dampened libido, to name a few.

Epilepsy is one neurological disorder that in past studies has illustrated an effect of carbohydrates on the brain. When carbohydrates are kept very low, the brain stops burning glucose as a fuel and instead turns to ketone bodies. This switch in the body’s metabolism has been successful as a treatment for epilepsy. Epilepsy patients who keep their carbs low enough have seen reductions in seizures even in cases where medication didn’t work well enough.

The keto diet appears to play a factor by calming the parts of the brain that cause seizures. Some researchers believe these neurological benefits could potentially extend to treating psychiatric disorders.

A May 2024 study published in the journal Psychiatry Research, led by researchers from the Department of Psychiatry and Behavioral Sciences at Stanford Medicine, aimed to put the keto diet to the test with people who had been diagnosed with bipolar disorder and schizophrenia. The researchers stated that dietary management of certain psychiatric disorders would be a game-changer, as medications can often be life-altering as they result in weight gain, metabolic side effects, and reduced life expectancy. If reducing carbohydrates were to work, these medications could potentially be lowered or stopped.

The study recruited 23 participants, who were being treated for bipolar disorder or schizophrenia who were either overweight based on their body mass index (BMI), or who were suffering from at least one “metabolic abnormality,” such as insulin resistance or elevated triglyceride levels.

The researchers requested that the participants eat a ketogenic diet for four months. The participants, who were an average of 43 years old, were instructed to eat no more than 20 net grams of carbohydrates per day after they subtracted the grams of fiber from the “total carbohydrate” content. They were also instructed to eat six times more healthy fat grams than carbs, and three times more grams of protein than carbs.

The participants were assessed at the beginning of the study, the mid-point, and after four months. Even with varying levels of adherence to the strict diet, all participants saw a reversal of metabolic syndrome and several other positive mental effects.

Overall, there was a 69% improvement in bipolar symptoms and a 32% improvement in schizophrenia symptoms.

Other metabolic markers also improved, such as triglyceride levels, blood sugar stability, and inflammation markers. Additionally, 17% of participants reported improved life satisfaction, and 19% reported better sleep.

Participants also experienced an average weight loss of 10%, and a 27% reduction in belly fat without counting calories. Those who could fully adhere to the strict diet, approximately 65%, saw even better results.

If those results sound life-changing, it’s probably because they were. Several participants praised the study for its impact on their wellbeing—one shared, “Since being on the diet, I haven’t noticed any significant anxiety level or attacks.” Another considered the changes lifesaving: “It can honestly save a lot of lives, it saved mine. I would not be here today if it wasn’t for keto.”

The study, though small, highlights the important need for more studies surrounding diet and mental wellness. “Mental health and physical health are interconnected, and addressing metabolic issues can complement psychiatric treatment to enhance overall well-being,” say the researchers. 

If you want to try the keto diet or you want to reduce carbohydrates, be aware there can be side effects like lowered energy, the “keto flu,” constipation, and potentially bad breath. Be sure to consult a healthcare provider if you are considering any change to your way of eating to ensure it is safe for you.

For more wellness updates, subscribe to The Healthy by Reader’s Digest newsletter and follow The Healthy on Facebook and Instagram. Keep reading: