The Spike & Crash
High-glycemic meals trigger rapid insulin release, causing a blood sugar crash that the brain interprets as a threat.
Steady Energy
Protein-forward meals and movement create a gentle rolling curve, providing consistent fuel and keeping the nervous system calm.
Can blood sugar affect anxiety?
Yes. Rapid blood sugar drops (especially after sharp spikes) can trigger a physiological stress response that mimics anxiety symptoms perfectly: internal agitation, shakiness, palpitations, and a sense of urgency. Mild to moderate hypoglycaemia is a well-studied trigger for autonomic and hormonal activation, which is why your "anxiety" might actually be a physiological alarm bell.
- Anxiety spikes mid-morning or mid-afternoon
- Feeling “wired but tired” (especially with high caffeine)
- Irritability or low mood when meals are delayed
- Waking 2–4am with a racing mind
- Skipping breakfast then feeling overwhelmed later
- Snacking all day yet feeling flat or anxious
- Energy drinks + sweet foods = emotional swings
- Late afternoon “meltdown window” after school
Can blood sugar affect depression?
Depression is multi-factorial, but metabolic stress can heavily contribute to fatigue, low drive, poor sleep, and reduced resilience. Nutritional psychiatry research—including landmark randomised trials—shows that dietary pattern improvements can significantly reduce depressive symptoms for some people, especially when their baseline diet quality is low.
Blood sugar and PTSD
Trauma-related conditions often involve hyperarousal, sleep disruption, and a heightened sensitivity to stress. Blood sugar swings amplify this by adding physiological “noise” to the system—especially if someone is already running a high sympathetic (fight-or-flight) tone. Stabilising meals, caffeine intake, and glucose variability can remove one major layer of stress signalling, paving the way for somatic regulation work.
Diet and ADHD: What the Dutch research shows
International research out of the Netherlands has explored the concept of a diet-sensitive subgroup in ADHD. A landmark trial (INCA) reported significant symptom improvements for some children on a strictly supervised elimination diet, with symptoms returning when foods were reintroduced. More recent work (TRACE) has examined how these diets compare to standard healthy eating guidelines over longer periods.
How we prepare before arrival (CGM + Mood Tracking)
At Goodsky, we often begin our preparation phase about a month before a guest arrives. Where appropriate, guests may wear a Continuous Glucose Monitor (CGM) for a short period. We do not use this as a treatment, but as an incredible feedback tool. Paired with simple mood tracking, CGM data often reveals patterns like:
- Glucose spikes immediately followed by irritability or anxiety
- Crashes perfectly aligning with daily “overwhelm windows”
- Late or high-sugar meals directly contributing to poor sleep quality
For teenagers in particular, seeing this objective data can dramatically reduce shame and blame. The narrative shifts from "I am broken" to "My body is reacting to fuel, and I have the power to influence it."
Do you need to go low carb or keto for mental health?
Not everyone. Many people see massive improvements simply by removing the obvious drivers of glucose volatility (skipped meals, “naked carbs” eaten without protein, high-sugar snacks, energy drinks) and focusing on whole foods. However, for individuals with marked glucose instability or metabolic dysfunction, a carbohydrate-restricted approach may be a highly useful tool for a period of time. Emerging metabolic psychiatry research from institutions like Stanford is exploring ketogenic interventions for serious mental illness, showing promising improvements in both metabolic markers and psychiatric symptoms.
| What it looks like | High Blood Sugar Instability | Steady Blood Sugar Stability |
|---|---|---|
| Daily Energy | Spikes, rapid crashes, severe afternoon slumps | Even, predictable energy without sudden "wipeouts" |
| Anxiety Levels | Surges closely following meals or extreme hunger | Fewer physiological surges; a steadier internal baseline |
| Sleep Quality | Waking up overnight (often 2-4am); restless sleep | More stable sleep continuity and deeper rest |
| Teen Behaviour | High volatility and reactivity during “crash windows” | Greater regulation and improved capacity for coping skills |
Practical strategies that flatten glucose swings
Eating vegetables first, followed by protein and fats, and finishing with starches/sugars can significantly reduce post-meal glucose peaks.
- Start with a salad, broccoli, cucumber, or carrots
- Move to protein (eggs, meat, fish, yoghurt) + healthy fats
- Save the starch/sugar for last (if included)
A short walk immediately after eating supports your muscles in taking up glucose, drastically reducing the subsequent “crash.”
- Just 10 minutes is enough to make a difference
- Especially helpful after dinner and for teens who sit all day
Clinical trials suggest vinegar consumption before higher-carb meals can reduce postprandial glucose and insulin responses.
- Common method: 1 tbsp apple cider vinegar diluted in a tall glass of water
- An optional tool—not essential, and not suitable for everyone
This is one of the simplest, most effective ways to reduce morning volatility and prevent mid-morning anxiety crashes.
- Focus on eggs, Greek yoghurt, meat, or a savoury breakfast
- If you eat carbs, always pair them with protein and fibre
Parent tips: What you can do this week
- Start with breakfast stability: Make the first meal protein-forward; avoid sweet breakfasts as the default.
- Change the order, not the meal: Add a fibre “starter” before the main meal (serve veggies first while cooking the rest).
- Pair carbs every time: Avoid “naked carbs”—if they are having a snack, ensure it is paired with a protein or fat source.
- Use a short walk as a reset tool: A 10-minute family walk after dinner can improve sleep and reduce evening reactivity.
- Reduce energy drinks gently: Sudden caffeine withdrawal can backfire; aim for a steady, phased reduction.
- Consider a short CGM period: If your teen is open to it, pair a monitor with simple mood tracking to build objective insight rather than subjective arguments.
Frequently Asked Questions
Is blood sugar only relevant if someone has diabetes?
No. Glucose variability can profoundly affect energy, sleep, and mood even in people without diabetes—especially when meals are irregular, high in refined carbohydrates, or paired with high caffeine and chronic stress.
Does going low carb or keto “treat” mental illness?
While not a universal cure, emerging research is showing profound potential. For example, recent clinical trials from Stanford Medicine demonstrate that ketogenic interventions can significantly assist in managing serious mental illnesses, including bipolar disorder and schizophrenia, by improving both metabolic and psychiatric markers. For many individuals, carbohydrate reduction acts as a powerful stabilising tool. At Goodsky, we frame this metabolic stability as a foundational support layer used alongside psychotherapy and nervous system regulation.
Is the "food order" approach evidence-based?
Yes. Controlled studies show that eating vegetables/fibre and protein before carbohydrates can significantly reduce post-meal glucose peaks. It is a simple, low-restriction strategy that is often easier for families to implement than changing the whole diet overnight.
Is a CGM necessary for recovery?
No, it is simply a short-term insight tool. Many people achieve metabolic stability without one. However, CGM data can accelerate learning—especially for teens who benefit from seeing the direct, real-time link between their physiology and their mood.
Ready to explore this in a structured setting?
If you’re an adult feeling stuck—or a parent supporting a teen with anxiety, mood volatility, or dysregulation—a structured, supported environment can make these foundational changes much easier to implement and sustain.
References & Further Reading
The following research and community resources are provided for transparency and self-education.
- McCrimmon RJ. Hypoglycaemia as a model for stress-induced brain dysfunction and altered decision making. Trends in Endocrinology & Metabolism. 2022. View
- Marks V, Teale JD. Hypoglycaemia: factitious and reactive states, symptoms and mechanisms. J Clin Endocrinol Metab. 1994. View
- Jacka FN, et al. A randomised controlled trial of dietary improvement for adults with major depression (SMILES). BMC Medicine. 2017. View
- Pelsser LMJ, et al. Effects of a restricted elimination diet on behaviour of children with ADHD (INCA). The Lancet. 2011. View
- Stevenson J, et al. TRACE study protocol / design and follow-up framework. Eur Child Adolesc Psychiatry. 2023. View
- Sethi S, et al. Ketogenic dietary intervention on metabolic and psychiatric health in bipolar disorder and schizophrenia. Psychiatry Research. 2024. View
- Shukla AP, et al. Food order (carbohydrates last) reduces postprandial glucose and insulin excursions. BMJ Open Diabetes Research & Care. 2015. View
- Food & Mood Centre (Deakin University). Explore Center
- Stanford Medicine: Metabolic psychiatry coverage. Read Article
The content provided in this blog post is for educational and informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician, psychologist, or other qualified health provider with any questions you may have regarding a medical condition or mental health concern.
