Food plays a huge role in mental health, especially when it comes to depression. One question I hear all the time as a holistic nutritionist is: are low-carb diets good or bad for mental health? Like most things in nutrition, there’s no one-size-fits-all answer—it all comes down to balance, context, and what works for you. It’s a nuanced topic that deserves a closer look, so let’s break it down.
The Role of Healthy Carbs in Neurotransmitter Production
Carbohydrates play a critical role in brain health by triggering an insulin response that drives tryptophan over the blood-brain barrier, where it’s converted into serotonin. Without enough healthy carbs, neurotransmitter production can falter, leading to increased feelings of anxiety or depression. Dr. Amen’s studies have shown that individuals with overfocused ADD need some complex carbohydrates in their diet to improve serotonin levels to help them shift gears. Without enough carbs, they may struggle to transition between thoughts or actions. High protein diets tend to exacerbate the situation, keeping them stuck on thought patterns and behaviors. This doesn’t mean you need to load up on bread and pasta, but incorporating nutrient-dense carbs like squash, quinoa, or even a small serving of fruit can make a significant difference.
The Fiber Factor: Low-Carb Diets and Constipation
Low-carb diets often cut out fiber-rich foods like whole grains, legumes, and starchy vegetables. Since fiber is essential for gut motility, going low-carb can lead to a low-residue diet, slowing digestion and causing constipation. This can indirectly affect mental health, as the gut and brain are closely connected through the gut-brain axis. Less fiber can also mean fewer probiotics that help produce serotonin (70% of it is made in the gut), potentially worsening depression symptoms.
To counteract this, prioritize non-starchy vegetables like cauliflower, broccoli, and cabbage, nuts, seeds, and low-carb fruits like berries to keep fiber intake sufficient. Trust me, your gut (and mood) will thank you.
Low-Glycemic vs. Low-Carb: A Better Approach
Instead of focusing solely on cutting carbs, consider a low-glycemic approach. This means prioritizing foods that have a minimal impact on blood sugar levels, such as:
- Instead of white rice: Try cauliflower rice or quinoa.
- Instead of white potatoes: Opt for sweet potatoes or Jersey yams.
- Instead of soda: Reach for sparkling water with a splash of fruit or Zevia.
- Instead of chips: Snack on celery, nuts, seeds, or almond crackers.
Keeping your blood sugar balanced is one of the best things you can do for your mental health. When your blood sugar drops too low or too fast, it can take your brain offline, making it hard to think clearly and leaving you vulnerable to poor decisions, cravings, irritability, and even anger. Ever notice how a panic attack feels eerily similar to a blood sugar crash? Sweating, shaking, confusion, and anxiety—they’re all signs your body is in distress. Keeping your blood sugar steady throughout the day can help prevent these symptoms and keep your brain functioning at its best.
My client, “D” was exhausted, anxious, and struggling to think clearly. His energy levels were all over the place, and he often felt lightheaded and unfocused. One afternoon, he called me from home, curled up under a blanket, feeling completely drained and miserable.
We walked through what he’d eaten that day. Breakfast was a sugary lemonade iced tea. He bought egg bites for protein but forgot to eat them. Lunch? Nonexistent. By 4 p.m., his blood sugar had plummeted, leaving him anxious, weak, and foggy.
I told him to grab some nuts, fruit, and cheese. Within 20 minutes, he felt like himself again. “D”’s relief was palpable. “If I can feel like this all day, that would be great,” he said.
Over time, “D” started paying closer attention to what and when he ate. He noticed that when he kept his blood sugar steady, he felt calmer, clearer, and more in control. The anxiety that once felt overwhelming became something he could manage—and for the first time in a long while, he felt like himself again.
Minerals and Mental Health
Many of the essential minerals our bodies rely on for mood and mental well-being come from complex carbohydrates. Magnesium, chromium, and zinc play a key role in stabilizing blood sugar and supporting brain function. Magnesium helps with relaxation, chromium curbs sugar cravings, and zinc supports neurotransmitter activity. When we drastically reduce carbs, we risk cutting out some of these key nutrients. Including mineral-rich foods like leafy greens, nuts, seeds, and legumes—rather than completely avoiding carbs—can provide a more balanced approach to mental and physical health.
Eating Carbs Seasonally for Mental Health
Seasonal eating aligns with what our bodies naturally need. In the winter, root vegetables like sweet potatoes and parsnips provide complex carbohydrates that help stabilize blood sugar and support serotonin production. Lighter, cooling fruits like watermelon and berries are more appropriate in the summer. These seasonal shifts in diet can help maintain balance in energy and mood throughout the year.
One of my favorite seasonal treats? A hearty winter soup with cannellini beans and carrots—perfect for those colder months when we crave grounding foods that also support mental well-being.
Refined Sugar and Artificial Sweeteners: Mental Health Saboteurs
Refined sugar creates a rollercoaster of blood sugar highs and lows, which can wreak havoc on mood. It also feeds candida overgrowth and is linked to brain fog and emotional instability. But what about artificial sweeteners? Many people turn to these thinking they’re a “healthy” alternative, but they come with their own baggage.
Artificial sweeteners like Splenda, NutraSweet, and Equal have been associated with side effects like headaches, mood swings, and even long-term health risks such as increased risk for Alzheimer’s and metabolic syndrome. These sweeteners can disrupt the gut microbiome and contribute to insulin resistance—not exactly a recipe for mental wellness.
Instead, I recommend natural options like stevia or pure monk fruit extract. Just be cautious of blends containing sugar alcohols, as these can upset your gut.
The Bottom Line
Low-carb diets can be beneficial for some individuals, especially for weight loss or managing diabetes. However, when it comes to mental health, the focus should be on balance rather than extremes. Prioritize low-glycemic, fiber-rich carbs, and consider seasonal and whole-food options to support stable blood sugar and optimal brain function.
If you’re struggling with depression, anxiety, or mood swings, remember that food is medicine. Small, sustainable changes in your diet can lead to profound improvements in your mental well-being. And if you need personalized guidance, I’m here to help!