The method, in the open
How Kinra learns your metabolism.
Kinra's plan is a deterministic engine, not a black box. It starts with a standard formula, learns from your weigh-ins and your logged meals, and updates gently — with guardrails. Here's the whole method, in plain language and with the math, cited to the research it's built on.
This is general wellness support for healthy adults — not medical advice, diagnosis, or treatment. Calorie and macro targets are coaching estimates. Talk to a qualified clinician about medical questions, pregnancy, or disordered eating.
The plain-language version
Six steps, no jargon required.
- 01
A first estimate. Onboarding uses the Mifflin-St Jeor resting-energy equation times an activity factor. It's only a starting point — a prior, not a verdict.
- 02
Trend weight. Your daily weigh-ins are smoothed into a trend so day-to-day noise doesn't move your plan.
- 03
Learned expenditure. As logs and weigh-ins build up, Kinra estimates what you actually burn from the energy balance between what you ate and how your trend moved.
- 04
Confidence. The learned estimate earns more weight when you have enough complete days, dense weigh-ins, and low variance.
- 05
Gentle holds. If the learned number looks implausibly high next to the formula, Kinra holds — and tells you your logging looks lighter than usual, without blame.
- 06
Weekly target changes. Kinra compares planned and observed pace, ignores small differences, halves the correction, and caps it. Small adjustment, not a reset.
The ideas that make it work
Trend weight, not the scale
Daily weight is noisy — water, sodium, a big dinner. Kinra smooths your check-ins into a trend with a time-aware 10-day constant, so a gap between weigh-ins doesn't distort it and one heavy morning doesn't scare you.
Observed expenditure
Once you've logged enough, Kinra estimates what you actually burn from your intake and your weight trend — not a fixed formula. Log ~2,000 kcal while your trend falls about 0.5 kg/week and your observed burn is roughly 2,550 kcal/day.
Confidence, always
The engine reports high, medium, or low confidence based on how many complete days and weigh-ins it has. When the data is thin or noisy, it says so and holds your target instead of guessing.
Gentle weekly updates
Kinra compares your planned pace to your observed pace, damps the correction by half, caps it at 150 kcal/day, and rounds to 10 — so your plan nudges, it never lurches.
Safety guardrails
Targets stay above 1,200 kcal/day for female profiles and 1,500 for male profiles, no more than 25% below your estimated burn in a deficit. After a long deficit or a stall, Kinra suggests a maintenance break rather than cutting lower.
Honest about the limits
Kinra doesn't claim lab-precise TDEE, doesn't predict long-term loss from a fixed rule, and doesn't infer body-fat or medical conditions. It flags when your logs and your trend disagree — gently, never as an accusation.
The math, for the curious
You never need to see this to use Kinra. But if you want to audit it, here it is — the same engine, no hidden magic.
Resting-energy prior
Mifflin-St Jeor, times an activity factor. A sensible start, not ground truth.
REE = 10·kg + 6.25·cm − 5·age + sex sex = +5 (male) / −161 (otherwise) prior_TDEE = REE × activity_factor
Trend weight
A time-aware exponential smoothing with a 10-day constant.
alpha = 1 − exp(−days_since_last / 10) trend = prev_trend + alpha·(weight − prev_trend)
Observed expenditure
Energy balance over 14–28 day windows (7,700 kcal/kg as a short-window approximation).
tissue_energy = Δtrend_kg × 7700 / days observed_TDEE = avg_logged_kcal − tissue_energy
Weekly adjustment
Damped by half, capped at 150 kcal/day, rounded to 10. A deadband holds tiny differences.
rate_error = desired_rate − observed_rate (kg/wk) delta = round10(rate_error × 7700 / 7 × 0.5) delta = clamp(delta, −150, +150)
Selected references
The engine is built on published, peer-reviewed work. A fuller list ships with the app.
- Mifflin MD, St Jeor ST, et al. A new predictive equation for resting energy expenditure. Am J Clin Nutr. 1990.
- Hall KD, et al. Quantification of the effect of energy imbalance on bodyweight. Lancet. 2011.
- NIDDK. Research Behind the Body Weight Planner.
- Hall KD. What is the required energy deficit per unit weight loss? Int J Obes. 2008.
- Morton RW, et al. Protein supplementation and resistance-training gains: a meta-analysis. Br J Sports Med. 2018.
- Rosenbaum M, Leibel RL. Adaptive thermogenesis in humans. Int J Obes. 2010.
A coach that shows its work.
Kinra publishes its method because trust should be earned, not claimed. Be first when it opens.