Project brief · September 2026

Chronie Bronie

A family-designed food-awareness and pattern-tracking tool for a young person living with Crohn’s disease and a small-intestinal stricture.

Project premise. Protein remains the primary positive goal, with sugar and a rolling estimate of recent food load presented as supporting guardrails. The application is designed for awareness and shared learning—not diagnosis, treatment, or symptom prediction.

Explore the demonstration Read the project brief

The visual identity is intentionally approachable; interpretation remains conservative.

01 · Abstract and rationale

A practical tool for making cumulative food load visible.

Chronie Bronie is a mobile-first, family-designed tracking application created around one practical problem: helping a young person with Crohn’s disease and a small-intestinal stricture recognize when the texture and cumulative burden of recently eaten foods may deserve attention, without moralizing food or claiming to predict obstruction.

The application combines a positive protein goal, sugar tracking, a pre-graded food library, a rolling Bronie Meter, and a brief nightly self check-in. Its central design decision is the separation of a food’s B0–B4 reference grade from a continuous, time-decaying daily load score. The grade supports quick logging; the meter reflects dose, timing, and accumulation.

Gluten is not treated as a direct cause of Crohn’s disease or as an inherently undesirable ingredient. The practical concern is mechanical: certain foods, textures, or combinations may be harder to move through a narrowed segment of small intestine, particularly when several higher-burden choices are eaten close together. Precision is not assumed at the outset. The objective is to identify plausible patterns and allow lived experience to refine the model.

Low interaction burden

Select a familiar food, adjust the serving, and record it.

Pre-graded library

The library reflects a manageable set of foods actually eaten.

Neutral framing

No “good food/bad food” language and no claim that a score predicts symptoms.

Transparency

The meter exposes its score and the foods contributing most.

Adaptability

Parent controls allow refinement while preserving mathematical constraints.

Clinical humility

Observations support discussion with clinicians; they do not replace care.

02 · Product overview

Three signals, one visible record.

The Today screen presents protein progress toward a daily goal, sugar against a configurable daily limit, and a rolling Bronie Meter that summarizes recent cumulative food load. The timeline preserves the underlying record so the meter does not become an unexplained verdict.

Core workflow

Choose a familiar food from the pre-graded library or predictive search.
Confirm time and serving amount, then add the food to the timeline.
Review protein and sugar totals and the rolling Bronie visual.
Open the meter explanation when additional detail is useful.
Complete the nightly check-in about stomach comfort, energy, and context.
Review weekly and monthly patterns rather than reacting to one meal or day.

03 · Food library and reference grades

The B grade belongs to a food.

Each familiar food receives a family-defined starting estimate of potential mechanical burden in the context of a known stricture. It is not a gluten scale, nutrition score, or medical risk classification.

Grade	Working interpretation	Typical characteristics	Illustrative examples
B0	Minimal expected burden	Smooth, soft, low-residue, or liquid	Milk, yogurt, eggs, smooth cheese
B1	Low burden	Generally soft or refined; modest texture	Soft tortillas, rice, tender ground foods
B2	Moderate burden	Breaded, dry, dense, or refined wheat-based	Crackers, nuggets, fries, plain burgers
B3	Higher burden	Dense dough, larger refined-wheat portions, or tougher texture	Pizza, sandwiches, pretzels, bagels
B4	Highest starting caution	Hard-to-chew, stringy, seeded, fibrous, dry, or personally difficult	Foods individualized from experience and clinician guidance

How a starting grade is assigned

Begin with published stricture and low-fibre guidance, including softness, moisture, peeling, deseeding, cooking, blending, and thorough chewing.
Evaluate the actual serving form rather than the ingredient list alone.
Treat wheat or gluten as one possible contributor to texture and density, not a universal trigger.
Keep protein and sugar separate; neither determines the B grade.
Review the estimate against personal experience and revise it deliberately.
Document uncertainty related to brand, preparation, serving size, hydration, disease activity, and individual tolerance.

04 · Rolling load model

The Bronie Meter belongs to a moment in time.

The meter is a separate continuous score. It allows low-grade foods to accumulate without implying that several B1 foods are automatically equivalent to one B4 food, and lets every food’s effect diminish over time.

baseᵢ = gradeImpact(Bᵢ) × servingsᵢ^0.75Bronie load = 0.70 × Σ recentᵢ + 0.30 × Σ dayᵢ

Tapping the visual meter exposes the continuous score, the recent and 24-hour components, and a ranked list of the foods contributing most. The primary meter does not display a B number, avoiding confusion between a time-sensitive score and an individual food grade.

Element	Current default	Purpose
Food-grade weights	B0=0; B1=1; B2=3; B3=7; B4=15	Makes higher grades disproportionately influential.
Serving adjustment	servings^0.75	Adds burden for more food while softening simple multiplication.
Recent component	0–2h: 100%; 2–4h: 70%; 4–6h: 40%; 6–8h: 15%	Responds to clustered intake and reaches zero after eight hours.
24-hour component	0–6h: 100%; 6–12h: 65%; 12–18h: 35%; 18–24h: 15%	Retains slower context from the remainder of the day.
Component blend	70% recent + 30% 24-hour	Prioritizes recent intake without discarding earlier context.
Display thresholds	<4; 4–7.9; 8–13.9; ≥14	Maps the score to Cruising, Heads up, Take it easy, and Bronie zone.

05 · Parent calibration tools

The Bronie Meter Lab.

A parent or administrator taps Settings → About Bronie Factor five times to open the implemented calibration screen. The controls modify the model while enforcing internal mathematical constraints.

Grade weights and load blend — Grade weights and component blend

Serving and recent decay — Serving response and recent decay

24-hour decay and thresholds — 24-hour decay and display thresholds

Control group	Adjustable values	Dependency behavior
Grade weights	B1–B4; B0 fixed at zero	Maintains B1 < B2 < B3 < B4. Moving one control nudges neighbors when required.
Blend	Recent and 24-hour percentages	Always totals 100%; raising one automatically lowers the other.
Time behavior	Four recent and four 24-hour decay bands	Later bands cannot exceed earlier bands; linked values move when needed.
Serving response	Exponent, initially 0.75	Bounded to preserve diminishing returns and avoid implausible amplification.
Meter bands	Four ordered display thresholds	Thresholds remain ordered and cannot cross.
Actions	Reset defaults; close; save and apply	Draft changes update the preview; saving persists the algorithm.

Recommended evaluation scenarios before saving

Five B1 foods compared with one B4 food.
The same foods clustered within two hours compared with distribution across a day.
One, two, and three servings of the same food.
A higher-load evening followed through the next morning’s decay.
A known comfortable day and a known difficult day used as anchors—not proof.

Calibration should remain conservative. A repeated family-observed pattern may justify reviewing a food grade or display threshold, but cannot establish a clinical obstruction threshold.

06 · Nightly self check-in

Exposure data paired with lived experience.

The nightly interaction asks three deliberately small questions: stomach comfort, energy level, and whether there is anything worth remembering. The supportive closing response appears only after submission.

Food logs describe exposure; they do not describe experience. The check-in provides a brief, repeatable outcome measure without requesting symptom detail every time food is recorded.

Input	Use in reports	Interpretive caution
Stomach comfort	Five-level ordinal daily outcome	A single rating may summarize several symptoms and contexts.
Energy	Three-level secondary outcome	May reflect sleep, school, activity, inflammation, medication, and mood.
Optional note	Context for preparation, illness, stress, travel, or unusual days	Free text is valuable but inconsistent and potentially sensitive.

07 · Reports and personal-pattern analysis

Weekly recall and monthly trend review.

Weekly history supports recall and makes meal timing understandable. The month view displays broader protein, sugar, Bronie, and check-in trends while preserving access to individual days.

The appropriate research question is not “Did food X cause a symptom?” It is “Do certain load patterns tend to occur before or alongside worse self-reported days for this individual?”

Domain	Candidate daily features
Bronie exposure	Peak, average, and end-of-day score; hours above each band; number and size of spikes
Food pattern	B0–B4 counts; largest contributor; serving-adjusted load; meal spacing; late-evening load
Nutrition	Protein total and goal attainment; sugar total and limit status
Self report	Stomach comfort; energy; completion; optional contextual note
Timing links	Same-day, 6–12-hour, overnight, and next-day associations

A cautious correlation workflow

Plot raw time series first and preserve missing days.
Compare higher-load and lower-load days using medians and distributions, not averages alone.
Examine multiple lags rather than assuming which window a nightly rating reflects.
Stratify obvious contexts when possible, including illness, travel, medication changes, menstrual cycle, active flare, or unusually low hydration.
Require repeated patterns over several weeks before changing a grade or setting.
Present associations as hypotheses for clinical discussion, not causal or predictive findings.

08 · Research methodology

Pragmatic, participatory, and hypothesis-generating.

The project combines clinical guidance, structured food analysis, participatory design, explainable algorithm development, longitudinal single-person observation, and mobile usability evaluation.

Layer	Method	Contribution
Clinical framing	IBD organization and hospital dietetics guidance; treating-team review	Defines the mechanical stricture context and discourages unsupported restriction.
Food grading	Review of texture, fibre/residue, seeds/skins, density, moisture, chewability, portion, and preparation	Creates a transparent best-estimate B0–B4 starting grade.
Participatory refinement	Young person and parent revise foods based on experience and usability	Keeps the library relevant and supports agency.
Algorithm design	Nonlinear weights, serving softening, time decay, component blending, and sensitivity scenarios	Transforms discrete grades into a rolling, explainable load.
Longitudinal observation	Repeated meal logs, nightly check-ins, and weekly/monthly descriptive reports	Generates personal hypotheses about patterns and time lags.
Usability evaluation	Mobile-first review of readability, tap targets, overlays, search anchoring, and logging friction	Reduces burden and supports consistent use.

Source hierarchy and evidentiary limits

Clinical and dietary framing is anchored in reputable patient guidance from IBD organizations and hospital dietetics services. Product decisions are adapted to the individual context. Commercial nutrition values are changeable reference data and should be checked against current labels or restaurant information. Lived experience informs personalization but does not supersede medical advice.

Repeated observations may improve recall and reveal within-person patterns. They cannot demonstrate that a food caused pain, inflammation, or obstruction. There is no control group, exposures are self-selected, symptoms and logging may influence one another, and many confounders remain unmeasured. The work is best described as participatory design and hypothesis-generating n-of-1 observation.

09 · Safety, ethics, and limitations

Not an obstruction detector

Severe or escalating symptoms require the established clinical plan and urgent medical guidance as appropriate.

Not a validated scale

Food grades are individualized estimates and are not generalizable to all people with Crohn’s disease or strictures.

Awareness, not restriction

A higher score should not produce guilt, punishment, or automatic restriction.

Nutritional adequacy matters

Changes to fibre, texture, or food variety should be discussed with an IBD-focused dietitian or treating clinician.

Privacy and assent

The young person’s assent, privacy, and control over notes should be respected. Public demonstrations use synthetic data.

Versioning

Food grades and algorithm settings should be versioned so later interpretation reflects the model active at the time.

10 · Development priorities

Next steps.

Add fixed comparison scenarios to the Meter Lab and record algorithm version history.
Extend month reporting with additional trend views and individual-day drill-down.
Add de-identified report exports that omit free-text notes by default.
Define a prospective observation period before changing settings, followed by clinical review.
Measure logging completion, check-in completion, time to log, and explanation comprehension.
Continue revising the interface with the young user so it remains supportive and understandable.

Conclusion

Chronie Bronie converts a complicated family concern into a consistent daily record: familiar foods, protein progress, sugar context, cumulative load, and the experience of the person who lived the day. Its purpose is to make uncertainty visible, discussable, and refinable over time.

Open the two-month synthetic demonstration

Selected references