When the brain runs out of fuel, mood is the first thing to go.

I’ve lost count of how many people have sat across from me on three different antidepressants, and not one of their providers had ever asked them what they eat for breakfast.

That’s not a knock on their providers. The system wasn’t built to ask those questions, and fifteen-minute appointments don’t leave room for them even when the curiosity is there. It’s a structural problem, not a character flaw—and I’ve written about that disconnect before.

What I want to talk about here is what I see on the other side of that gap. Because over the past two years, working across hundreds of clinic patients and private clients at various stages of metabolic dysfunction, one pattern has emerged more consistently than almost anything else: when we improve someone’s metabolic health, their mental health tends to follow.

The vast majority of the time. Across conditions. Across ages. Across backgrounds.

That’s not a small number.

The Pattern Nobody Warned Me About

When someone switches over to a ketogenic or carnivore approach, I expect to see changes in their blood sugar, their triglycerides, their inflammatory markers. That’s the whole point. What I didn’t expect—at least not to this degree—was how reliably their mood would shift alongside those numbers.

We track mood in our clinic. We track it the way we track bowel habits and sleep quality and energy levels—because it’s a data point, not a sidebar. What the data keeps showing us is that as insulin sensitivity improves, as inflammation comes down, as blood sugar stabilizes, mood scores climb in parallel. Not sometimes. Almost every time.

Many of the people I work with notice significant improvement in their anxiety within the first two weeks. Brain fog clears—like someone turned the lights on in a room they’d been fumbling through for years. It’s one of the most common things people report, and it’s one of the things that keeps them engaged with the process when the scale isn’t moving yet. The healing phase is doing its work; the mind just happens to be one of the first places where it shows.

Low Mood as a Hunger Signal

This is something a lot of people don’t realize, and it’s one of the more important observations I’ve made in my clinical work so far.

When we start tracking how much fat and protein someone is actually consuming per day—actually writing it down and looking at the numbers—they’re almost always under-consuming. It’s incredibly common. Years of diet culture, calorie restriction, and fear of fat have left people chronically underfed at the cellular level; they might be eating enough volume, but they’re not getting enough of the raw materials their bodies need.

Once we troubleshoot that—once we get their fat and protein up to where their body can actually start rebuilding—their mood improves. Often within days. Not because we gave them a supplement or adjusted a medication, but because we gave their brain what it needed to function.

Low mood can be another hunger signal. The body doesn’t always tell you it’s starving through stomach growling. Sometimes it tells you through irritability, through brain fog, through that flat, low-grade depression that just sits on everything and makes the world feel gray. If the raw materials for building and rebuilding aren’t in place—if the energy systems that run every cell in your body aren’t getting what they need—then how can the mind function properly?

It can’t. Not really.

The Research Is Starting to Catch Up

The clinical observations I’ve made over the past two years aren’t happening in a vacuum. The emerging field of metabolic psychiatry is building a serious evidence base for what people in this space have been watching unfold in real time.

A pilot trial out of Stanford studied individuals with schizophrenia or bipolar disorder who were placed on a ketogenic diet for four months. Among adherent participants, those with schizophrenia experienced significant reductions in psychiatric symptom scores; overall clinical severity improved meaningfully across the group. Simultaneously, metabolic markers improved—weight, insulin resistance, triglycerides—all moving in the right direction at the same time as the psychiatric improvements. The parallel was hard to ignore.

A separate retrospective analysis looked at 31 inpatients with severe, treatment-resistant depression, bipolar disorder, and schizoaffective disorder who were placed on a ketogenic diet as an adjunct to their conventional care. Depression scores dropped substantially. For the patients with schizoaffective illness, psychiatric symptom scores improved dramatically. These were people whose conditions had been classified as refractory—meaning conventional approaches hadn’t been able to get them under control. Co-authored by Dr. Eric Westman from Duke and Dr. Georgia Ede, both of whom are key voices in this conversation.

A large meta-analysis spanning 70 studies and over 240,000 participants confirmed that insulin resistance is elevated during acute depressive episodes. The relationship between metabolic dysfunction and mood disorders isn’t theoretical anymore; it’s measurable, reproducible, and being studied at major research institutions.

This is the part where I’d normally hedge. In my experience, so far, the research is still young enough that I don’t want to overstate what we know. Time will tell how the clinical trials scale. What I can say is that the research is pointing in the same direction as what I see in clinic every single day—and when those two things line up, I pay attention.

Beyond Depression and Anxiety

The conditions I’ve seen respond to dietary and lifestyle change extend well beyond depression and anxiety. People dealing with symptoms of ADHD, OCD, and bipolar disorder have been able to reduce or entirely eliminate those symptoms by altering their diet, how they move, their light environment, their sleep, and their stress response.

Some of the people I’ve worked with over the years—and many of my colleagues locally and in other clinical settings—have seen meaningful improvement with conditions like schizophrenia, ALS, Parkinson’s, and Alzheimer’s. These aren’t guarantees. These aren’t promises. These are observations from the clinical trenches that deserve further investigation rather than dismissal.

My own father recovered faster from a stroke than anyone on his care team had ever seen. We made sure he had ample animal fats and protein throughout his recovery. He also declined taking a statin, which they attempted to push on him aggressively while he was in the hospital and during rehabilitation. I’m not saying that’s the protocol for everyone. I’m saying his recovery was remarkable, and the people around him noticed.

This One Is Personal

My own mother was diagnosed with bipolar disorder when I was young. I presented with all of the same symptoms and behaviors she did—the mood swings, the volatility, the patterns that felt hardwired and permanent—up until I switched over to what has now been over eight years of living a carnivore lifestyle.

I can’t go back in time and save myself sooner—or my mom—but I can continue my education in hopes that the information reaches someone who needs it. That’s what this work is for me. It’s not abstract. It’s not academic. It’s deeply, uncomfortably personal; every person I sit across from who’s struggling with something I recognize from my own story reminds me why this matters.

That doesn’t make me an expert on bipolar disorder or schizophrenia or any of the other conditions I’ve watched respond to metabolic intervention. What it makes me is someone who pays very close attention—because the stakes aren’t theoretical.

The Throughline

The metabolic health framework isn’t just about blood sugar and body composition. It’s about the entire operating system. Your brain is the most energy-demanding organ in your body; it accounts for roughly 20% of your total energy expenditure despite being about 2% of your body weight. When the energy systems that power it aren’t working—when insulin resistance is disrupting glucose uptake, when inflammation is interfering with neurotransmitter production, when the raw materials for building and maintaining neural tissue are missing from the diet—the mind pays the price.

This is the modern environment at work. We’ve spent decades optimizing for convenience and cost at the expense of the inputs that actually keep human beings functioning. The result isn’t just metabolic disease; it’s a mental health crisis that keeps getting worse despite more people being on psychiatric medications than ever before.

I’m not anti-medication. I’m not telling anyone to stop their prescriptions. What I am saying is that if we’re not addressing the metabolic foundation—if we’re not asking whether someone’s brain is actually getting the fuel and raw materials it needs—then we’re trying to fix a power outage by replacing the lightbulbs.

I hope this connects some dots. I hope it gives someone permission to look at their mental health through a lens they haven’t been offered before. The body and the mind aren’t separate systems; they’re the same system, running on the same fuel, breaking down for the same reasons.

All that to say—mental health is metabolic health. It always has been.

Sources

  • Sethi S, Wakeham D, Ketter T, et al. “Ketogenic Diet Intervention on Metabolic and Psychiatric Health in Bipolar and Schizophrenia: A Pilot Trial.” Psychiatry Research, 2024. DOI
  • Danan A, Westman EC, Saslow LR, Ede G. “The Ketogenic Diet for Refractory Mental Illness: A Retrospective Analysis of 31 Inpatients.” Frontiers in Psychiatry, 2022. DOI
  • Fernandes BS, Salagre E, Enduru N, et al. “Insulin resistance in depression: A large meta-analysis of metabolic parameters and variation.” Neuroscience and Biobehavioral Reviews, 2022. DOI
  • Aucoin M, LaChance L, Naidoo U, et al. “Diet and Anxiety: A Scoping Review.” Nutrients, 2021. DOI
  • Ede G, Zupec-Kania BA, Masino SA. “Ketogenic metabolic therapy as a treatment for mental health disorders.” Frontiers in Nutrition, 2025. DOI

Rance Edwards is a National Board Certified Health and Wellness Coach (NBC-HWC) with over 2,000 clinical hours of experience, specializing in chronic disease management and lifestyle medicine.

If any of this resonated—or if you’ve been wondering whether your nutrition might be connected to how you feel mentally—I’d love to talk through it with you. Book a free discovery call—no pressure, just a conversation about where you are and what might help.

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