Why a 2am Feed Shouldn't Count as Tomorrow

By the Krestrel team · Published 26 August 2026 · 6 min read

Ask any parent tracking a metabolic diet what breaks their numbers, and you will hear some version of the same story. The overnight feed. The 2am pump. The 3am bottle after a seizure. The medicine given at 11:58pm because that is when the alarm went off.

Every one of those is ordinary care. And in almost every tracking app, every one of them lands on the wrong day.

The midnight problem

Nutrient trackers were built for adults counting calories, and adults sleep through midnight. So the apps drew the line there: a day starts at 00:00 and ends at 23:59, and whatever you log inside that window is "today".

That assumption falls apart the moment a child is fed overnight. If your dietitian has set a limit of, say, 100 mg of lysine per kilogram per day, that limit describes a feeding cycle — the stretch of care that runs from one morning to the next. It does not describe the calendar. But a midnight reset splits one feeding cycle across two calendar days, and the damage runs in both directions:

• Last night looks under. The overnight feed you gave at 2am never got added to it, so the day reads as though your child ate less than they did.
• Today looks over. That same feed is sitting in today's total before anyone has had breakfast, so the remaining allowance you plan the day around is already wrong.
• The trend chart lies twice. One artificial dip, one artificial spike, on a chart you may be showing your metabolic team at the next appointment.

The usual workarounds are worse than the problem. Some parents log the overnight feed the next morning with a fudged timestamp, which corrupts the timing data that makes a feeding log useful in the first place. Some keep a paper sheet alongside the app. Most just learn to mentally subtract, every single day, forever.

Day start: move the boundary to where your day actually begins

Krestrel lets a care circle decide when a day begins. In Settings → Day start, pick any hour from midnight through 11pm. Choose 7am and Krestrel's day runs 7am to 7am. A feed at 2am is counted toward the day that started the previous morning — because that is the day it belongs to.

That single setting reaches every surface where a "day" is a unit:

• Today's nutrient totals — the lysine, phenylalanine or protein gauge you check before deciding what to serve next.
• The timeline and day calendar — the overnight feed appears at the bottom of last night, where you remember giving it, instead of orphaned at the top of a new screen.
• Daily care stats — feeds, diapers, sleep, medicines, pumping sessions.
• The analytics trend chart and reports — the multi-day intake chart buckets meals by your day boundary, so the chart you export for the clinic agrees with the gauge you looked at that morning.

One of the quieter details matters as much as the setting itself: the boundary is stored on the care circle, not on a phone. A grandparent doing the evening shift, a co-parent on a night feed, and a night nurse all see the same day, the same running total, and the same remaining allowance. There is no version of the day that only one caregiver's device believes in.

Your history is regrouped, never rewritten

Changing the day start does not touch a single stored record. Every meal, feed and dose keeps the exact timestamp it was logged with; the day boundary only decides how those timestamps are grouped into days. Set it, look at last week, and change it back — nothing is lost either way.

Two details we sweated so you do not have to:

• Local time, honestly. "7am" means 7am where the caregiver is standing. Totals are computed against real instants, so a circle spanning time zones — a parent travelling, a relative helping from abroad — still adds up.
• Daylight saving does not skip a day. The day stepper walks calendar days rather than subtracting 24 hours of milliseconds, which is exactly the bug that makes other trackers show a duplicated or missing day twice a year, right at the boundary hour.

Choosing your hour

There is no correct answer, only your household's. A few patterns we see:

• Midnight (the default). Fine if nobody is fed overnight, and it matches how a food diary on paper works.
• 6am–8am. The most common choice for families doing overnight tube or bottle feeds. Set it to the hour the household genuinely gets up.
• The hour of the first scheduled feed. If care runs on a fixed schedule — common with pump feeds and timed medication — anchoring the day to the first feed of the cycle makes every day directly comparable to the last.
• Match the clinic. If your metabolic team counts a day in a particular way for a food record or a 24-hour collection, match them. Then the numbers you bring to the appointment need no translation.

That last one is the real payoff. A daily nutrient total is only worth recording if someone can act on it, and the person acting on it is usually your dietitian. A record where every day includes the whole feeding cycle it was meant to include is a record you can hand over without a caveat.

Small setting, honest numbers

Day start is one horizontal row of hour chips in Settings. It takes about three seconds to change. But it is the difference between an app that fits the way you already care for your child and one that asks you to do arithmetic at 2am to correct its assumptions.

Krestrel is a record-keeping tool, not medical advice — it does not recommend diets, restrictions or amounts. What it can do is make sure that the day it shows you is the day you actually lived.

Frequently asked questions

Does a 2am feed count toward yesterday or today?

That is your choice. With a 7am day start, a 2am feed belongs to the day that began the previous morning. With the midnight default, it starts a new day.

Can each caregiver set their own day start?

No, and deliberately so. The setting belongs to the care circle so that everyone looking at today's total is looking at the same total. Only a circle primary can change it.

Will changing it break my past data?

No. Entries keep their original timestamps; only the grouping changes, and it is reversible.