Guides
GNL Guides
All education and self-discovery guides on The Glucose Never Lies. Start with Foundations, then explore the areas most relevant to your life with type 1 diabetes.
Start here
Foundations
Foundations are the required starting point. These guides lock in safety, core principles, and baseline competence. Everything else on GNL assumes this knowledge is in place.
The essential building blocks: what type 1 diabetes actually is, insulin, CGM, carbohydrate, hypos, hypers, ketones, fast and slow movers, and measuring success. Twelve concept pages, anchored to the GNL evidence base, work through the sequence in order or jump to what you need most right now.
How to use the guides: Start with Foundations. After that, explore in any order: take what is useful now, and return as your needs change. Each guide describes average responses and mechanisms: use your CGM data and care team to interpret what you observe.
Self-discovery and experimentation
Observe. Learn. Adapt. Repeat.
Progress comes from observing real glucose patterns, making small and safe changes, and adapting based on what actually happens.
Why your 70% TIR target may not be the same as someone else’s. CGM zones, glycator biology, the mHGI calculator, and the personalised TIR target matrix. A five-part guide.
Explore →Sleep is metabolic, not a wellness layer. The mechanism (Donga 2010), the bidirectional loop, the dawn-phenomenon (Porcellati 2013), the OSA-in-T1D conversation (Banghoej 2017), and the regularity lever that costs no insulin and no hardware. A four-part flagship guide, hub plus four parts.
Explore →How to understand and work with glucose movement between meals: the mechanisms behind rising and falling trends.
Explore →How movement amplifies insulin sensitivity: and the mechanisms behind glucose changes during and after different activity types.
Explore →A framework for thriving with CGM: reading trends, understanding glucose context, and using data to guide self-discovery.
Explore →How the fat and protein content of meals affects glucose: and the mechanisms behind high-carb and high-fat meal responses.
Explore →The physiology of exercise with type 1 diabetes: hypo risk, insulin on board, glucose responses, and how they interact.
Explore →How the IOB setting works, why it matters for corrections, stacking, and exercise hypo risk: across different systems.
Explore →Why insulin resistance is more pronounced in type 1 and how it interacts with glucose patterns, body composition, and energy.
Explore →The mechanisms behind alcohol and drug interactions with glucose and insulin in type 1 diabetes: what tends to happen and why.
Explore →Life Stages and T1D
How the body changes through life with type 1 diabetes
From the first days after diagnosis in childhood, through puberty, the adolescent years, and on into menopause and older adulthood: the phases of a life with T1D each carry their own physiology, their own technology questions, and their own evidence gaps. These guides name the mechanism and the work the person is already doing.
Antibody screening identifies T1D years before clinical diagnosis. For children at Stage 2 (two antibodies plus dysglycaemic OGTT), teplizumab roughly doubles the time to clinical onset (Herold 2019 TN10, Sims 2021 extended follow-up). The evidence is real, the access is uneven, and the conversation is new. Sits within the wider Prevention and Cure cluster.
Explore the guide →The consolidated paediatric guide. Four age-band parts plus a hub: infants and preschoolers (under 6), school-age children (7 to 14), adolescents (15 to 17), and the transition to adult care (17 to 21). Carries the under-6 Dusk-Then-Drop pattern with per-system AID settings adjustments, the midday hypo trap, the school-day evidence (Pihoker 2023, Brown 2021), the adolescent quality-of-life cascade (Hilliard 2013) and DKA-on-AID safety signal (Karges 2024), and the eighteen-month transition plan to adult care. ISPAD 2024 routed; family voice throughout.
Explore the guide →Adults living with T1D, hub plus two parts: the twenties (algorithm strength and AIT trade-offs, stacking corrections, the six foundations in adult shape) and the working years from thirty to sixty-five (five life events with sensitivity direction arrows, settings-review triggers, and AID Optimiser §1 framing). Honest about what the evidence carries and what it does not.
Explore the guide →Older adults living with T1D, hub plus two parts: active older adults, and older adults needing more support. Floors discipline throughout (glucose floors, cognition floors, social floors), hypo unawareness mechanisms, deprescription conversations, and the evidence on AID in older age. ADA / EASD older-adult consensus routed; care-team partnership framed honestly.
Explore the guide →Female lifecycle, hub plus five parts: periods in young people, periods in adult life, planning a baby, pregnancy and after the birth, and menopause. Cycle-driven glucose patterns (Tatulashvili 2022 with the GNL Syno cohort triangulating), pre-conception care, the CONCEPTT signal, and the five UK hybrid closed-loop systems across each life phase. Family voice throughout, honest evidence-gap framing where the data is thin.
Explore the guide →Standalone deep-dive on cycle-driven glucose patterns: the follicular and luteal contrast, the late-luteal insulin-resistance window, how to read your own pattern across two to three cycles, and what the evidence carries on adjustment strategies. Sits inside the Female Guide for lifecycle context; called out separately here for anyone who needs the cycle pattern directly.
Explore the guide →Masters level / Reading the evidence
Once you can read the research, marketing and social nonsense cannot fool you.
A drug company representative arrives at clinic with a 78% time-in-range slide deck. A social media post claims a supplement reversed Type 2 in eight weeks. A clinic recommendation lands without a paper behind it. The guides above teach you the clinical content. This one teaches you the meta-skill: how to read any research study yourself, grade the evidence A to D, run the auditor’s ten-point checklist on anything you encounter, and live comfortably in the gap between what the trial showed and what the lived experience says.
Hub plus seven parts. The Goldacre lens on publication bias and the survivor’s lottery (Part 3). The Taleb lens on the population-versus-individual gap, the Black Swan, and skin in the game (Part 4). The clinic-floor reality of trial versus lived experience (Part 5). The ten-point TG Audit checklist you can run on any paper you encounter (Part 6). Built on Goldacre’s Bad Science / Bad Pharma / I Think You’ll Find, Taleb’s Antifragile / Skin in the Game / Black Swan, Greenhalgh’s How to Read a Paper 7e, the Cochrane Handbook v6.5, and twenty years of paediatric T1D clinic experience. The companion module to Grace’s Critical Appraisal mode in the app.
Who this is for: anyone living with T1D or T2D who wants to defend themselves against bad evidence; clinicians who want a written reference for the appraisal habits they already use; HCPs who want to teach evidence literacy without having to write the curriculum; journalists and family members who keep meeting confident claims without the data to support them.
Prevention, screening, and the research frontier
Where T1D research is heading next
The conversation has shifted. Antibody screening can identify T1D years before insulin is needed, teplizumab can delay Stage 3 in the right person, and the insulins on the horizon move the needle while a cure is still in trials. These guides map the frontier honestly: what is known, what is emerging, and what still has to be proved.
An honest map of prevention and cure efforts in 2026. The stages model, the antibody-positive years, and the trial pipelines that may change what ‘diagnosis’ means in the next decade.
Explore the guide →Antibody screening pathways (TrialNet, ELSA, Fr1da, TEDDY), what a Stage 1 or Stage 2 result means, and how the conversation with the family differs when there is time before insulin.
Explore the guide →The insulins coming next: ultra-rapid analogues, once-weekly basals, and the formulations that lift outcomes while a cure is still in trials. What changes day to day, and what to ask your team.
Explore the guide →Technology and Drugs
Technology and Drugs
Choosing and using the devices and adjunctive medications that move the needle: CGM, AID systems, skincare for technology users, and GLP-1 / GLP-1+GIP receptor agonists alongside insulin.
Choosing and using continuous glucose monitoring: accuracy, sensor selection, and getting the most from your device.
Explore the CGM Guide →Choosing and using the five UK-available hybrid closed-loop systems: Tandem Control-IQ, Tandem Mobi (CIQ+), MiniMed 780G, CamAPS FX, and Omnipod 5. How each algorithm works, the trade-off the system asks you to make, and what to explore with your care team. Flagship guide, hub plus four device pages.
Explore the AID Guide →Evidence-graded flagship guide on GLP-1 receptor agonists (semaglutide, liraglutide) and the dual GLP-1/GIP agonist tirzepatide alongside insulin in type 1 diabetes. ADJUNCT I/II, ADJUST-T1D (Shah 2025), the Park 2024 meta-anchor, the DTS consensus, safe starting protocols with insulin reduction bands, and the open paediatric and equity questions that remain. Off-label specialist-led territory throughout. Four parts.
Explore the Adjunctive Therapy Guide →Protecting skin while using CGM and pump devices: practical approaches to adhesion, reactions, and site care.
Explore the Skincare guide →Part of the CGM Series. Accuracy, simplicity, and what is next for the FreeStyle Libre platform: the sensor that brought CGM to the mainstream.
Listen to Episode 38 →The next generation of FreeStyle Libre: what the Libre 2 Plus and Libre 3 Plus bring to accuracy, connectivity, and AID integration.
Listen to Episode 39 →Not sure where to start?
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