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DecisConnect meals · caffeine · nutrition

If you eat dinner late tonight, how well will you sleep?

Decis finds the days in your records when you ate dinner late and the days you did not, and shows how your sleep and heart rate differed that night.

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Decis for diet experimenters

In the sample records, the 11 late-dinner days looked like this.

The simplest way to judge something before you do it is to look at your own past days that were like it.

Actual product UI · de-identified sample records
Sleeping heart rate after dinner within 3 hours of falling asleep
+4bpm
Deep sleep on those same nights
−11m
Meal logs over 28 days behind this comparison
79 meals

These differences come from de-identified sample records, and they do not show a cause. Connect your records to see your own numbers.

01Timeline

Your meals and that night

See meals and caffeine on the same time axis as sleep and heart rate.

What you ate and when lines up with the day's heart rate, workouts, events, and that night's sleep. Open a meal to see its carbohydrate, protein, and fat breakdown, key nutrients, and your intake for the day up to that point.

  • Meal and caffeine times next to your sleep on one axis
  • Open a meal for its macros and the day's running total
  • Micronutrients shown against general reference values
Loading the actual Timeline view
02Ask

Ask your own records

Ask in plain words. Decis answers from your own records.

Ask something like “Did my sleep change after I cut back on coffee?” and Decis looks through your connected sleep, training, meals, calendar, and work records, then answers conclusion first, followed by evidence, interpretation, and next action. The dates it checked and the records it was missing are part of the answer, so when the evidence is thin, it says so.

  • Ask in plain words, get evidence from your own records
  • Conclusion, evidence, interpretation, then next action
  • Dates reviewed, missing records, and correlation limits stated
AskActual product UI · de-identified sample records
Ask Decis5 answers left this month5 leftAnalyzable daily records: Jan 1, 2025–Jul 17, 2026Analyzable daily records2025-01-01–2026-07-17
You

Over the last four weeks, how did my sleep differ between nights after a late dinner and nights after an early one?

Decis

Conclusion

Over the last four weeks, nights when your last meal fell within three hours of bedtime tended to show a higher sleeping heart rate and less deep sleep. The difference was larger on days when that meal was big.

Evidence

  • Your last meal fell within three hours of bedtime on 11 of the 28 days. Sleeping heart rate on those nights averaged 58bpm, 4bpm above the 54bpm on other nights.
  • Deep sleep on those 11 nights averaged 47 minutes, 11 minutes shorter than the 58 minutes on other nights.
  • Of those 11 days, sleeping heart rate averaged 60bpm on the six days when the last meal exceeded 800kcal, and 56bpm on the five days when it did not.
  • Total sleep was 6h 49m and 6h 57m for the two groups, an eight-minute difference.

Interpretation

In these records, the later and larger the last meal, the higher that night's heart rate tended to be. Late dinners often coincide with late events or alcohol, and there were no alcohol logs in this period, so that effect could not be separated. This is an association, not a judgment about your health.

Next action

For the next two weeks, consider finishing your last meal three hours before bed on five days a week. On days when a late meal is unavoidable, consider a smaller portion and compare that night's records.

Data coverage

Reviewed 28 days from June 20 through July 17, including 79 meal logs, sleep stages, and sleeping heart rate. Four days with two or fewer logged meals were left out because the last meal time may be inaccurate.

Interpreted from your records · correlation may not mean causation
03Today

Today's records

See today’s wellness patterns at a glance.

Compare HRV, sleeping heart rate, and sleep duration with your usual range, then follow sleep stages and the balance between long-term fitness and recent fatigue on the same screen.

  • HRV and sleeping heart rate against your recent range
  • Sleep stages and the latest 14-day sleep trend
  • Fitness, fatigue, form, and daily training load
Actual product UI · de-identified sample records
Condition

Your recovery readings are in your usual range, and you slept well.

Today's conditionRoom to pushAll signals are within your usual range
Fitbit HRV · RMSSD (sleep)
Apple Health HRV · SDNN
HighAvgLowVery low
Sleep HRV
59msUsual 53–59

Based on Fitbit HRV · RMSSD (sleep)

Sleep HR
49bpmUsual 48.5–51.5

The morning recovery signal — resting HR arrives a day later

Resting HR
53bpmUsual 52.5–55.5

Your latest all-day resting heart-rate reading

This observation compares HRV and sleeping heart rate with your usual range over the last 60 days, and sleep with your personal sleep need. It does not determine safety or a medical condition.

04Calendar

Your schedule and the next day

Find which events leave you slow to recover the next day.

For every recurring event, like the weekly operations review, Decis gathers next-day HRV, sleeping heart rate, and sleep and shows how often it went that way, such as 6 of 8 times. You also see which weekdays and hours your meetings cluster in. A pattern is shown as a pattern, never as a cause.

  • How your body was after each recurring event, with the observation count
  • Next-day HRV, sleeping heart rate, and sleep duration
  • Meeting density by weekday and hour
Actual product UI · de-identified sample records
Last 3 months energy vampire · recurring event

Weekly operations review

On 6 of 8 occasions, next-day recovery moved in the same direction.

Apr 1, 2026–Jun 30, 2026
Repeated6 of 8 timesConsistently repeated
HRV-8 ms
Sleeping heart rate+4 bpm
Sleep duration-32 min
Basic stats

Your Last 3 months schedule in numbers

Covers Apr 1, 2026–Jun 30, 2026. Meeting figures include events classified as meetings; location figures include all events.

Meetings46 times
Meeting time49 hr 40 min
People met18 people
Days with meetings31 days
In person 13Video 27Phone 2Other 4
Busy meeting times
9:0012:0015:0018:00
Mon
Tue
Wed
Thu
Fri
Sat
Sun
Your busiest day was May 12, 2026: 5 meetings totaling 5 hr 10 min.

Questions diet experimenters ask

Compare your records after a change in how you eat.

Selecting a question fills the Ask composer first. Micronutrient values are shown against general reference values; Decis does not judge personal deficiencies or prescribe intake.

Answers that cannot reach a conclusion because records or sample size are insufficient do not use your question allowance.

Connections and privacy

Read only what you allow. Leave the originals untouched.

Connect Apple Health through the iOS app, Google Health by approving access with your Google account, and Google Calendar for read-only schedule context.

  • Apple HealthSync sleep, heart rate, HRV, activity, training, and nutrition through the iOS app
  • Google HealthSleep, heart rate, HRV, activity, and nutrition from supported devices
  • Google CalendarRead-only schedule context for Calendar insights and Ask
D
DecisToday’s wellness patterns from your connected records
Read only

Review requested permissions before connecting. Decis does not change records in connected services, and you can manage source-specific synced data and your Decis account data in Settings.

  • Minimal, read-only access

    Decis requests only the permissions needed for the feature and does not change originals in connected services.

  • Protected in transit and at rest

    Data in transit, stored data, and external-service connection credentials are encrypted.

  • Manage connections and deletion

    Remove a connected source or request permanent deletion of your Decis account in Settings. Applicable retention rules are described in the privacy policy.

See how Decis handles data

In the AI you already use

The Claude or ChatGPT you already use reads your records and answers.

Paste one address and you are done. Your AI queries more than 80 datasets, from sleep and recovery to meals, calendar, and agent work, and answers from your own numbers for that day. Read-only, and you can disconnect it on the Agents page at any time.

Claude · Decis connected

Can I run intervals tonight? I was reviewing code late last night.

Read from Decis · today’s brief, 14 days of sleep and HRV, yesterday’s agent sessions

Your records point to easing off one notch today.

  • 5h 48m of sleep last night against a 14-day average of 6h 52m
  • Morning HRV 43ms, 16% below your 51ms baseline
  • Yesterday’s Claude Code session ended at 23:40, and on all 5 near-midnight work days in the last 4 weeks, next-day HRV sat below baseline

Swap the intervals for 40 minutes easy and check tomorrow’s HRV.

De-identified sample records · days with the same conditions compared, no cause claimed.
  1. 01
    Paste one addresshttps://www.decis.me/mcp

    Works in Claude, ChatGPT, Cursor, or any app that supports MCP.

  2. 02
    Approve once in your browser

    You see what will be read before allowing it. There is no edit or delete permission to grant.

  3. 03
    Ask in plain words

    “Why is my sleep off this week?” “Should I cut today’s workout?” “How was the day after yesterday’s coding session?”

In the terminal and coding agents, use the CLI
brew install tab0inc/tap/decis-cli
decis data list --domain sleep
decis work connect pi

Connect Claude Code, Codex, and Pi work logs and read the same 80+ datasets straight from the terminal.

  • Claude
  • ChatGPT
  • Claude Code
  • Cursor
  • Decis CLI
  • Any MCP client

  • Read-only by design

    Connected AI apps can read your data but can never modify or delete it.

  • You consent, and you can revoke

    Each app is approved in your browser, and revoking it on the Agents page removes its access immediately.

  • 80+ datasets on a stable contract

    Sleep, nutrition, training, recovery, and schedule data served through a discoverable catalog and an OpenAPI contract.

How to connect and disconnect

Frequently asked questions

What to know before you begin.

The essentials about these product views, connections, answers, privacy, and health and wellness information.

Are these the actual product screens?

Yes. The UI components and visualizations used in Today, Timeline, Calendar, and Ask are rendered here from the same product code. The dates, values, and event names shown are public de-identified examples, not a user’s records.

Which records can I connect?

You can connect sleep, heart rate, HRV, activity, training, and nutrition records from Apple Health through the iOS app or from Google Health, and connect Google Calendar for read-only schedule context.

What happens when there is not enough evidence?

If records or sample size are insufficient for a conclusion, Decis explains what is missing and which records would help. That answer does not use your question allowance.

How is health data protected?

Decis uses read-only access within the scope you approve and encrypts data in transit, stored data, and connection credentials. You can manage connected sources and account data in Settings.

Can Decis give medical advice?

Decis organizes everyday wellness records and presents observed patterns. It does not provide medical diagnosis or treatment. Confirm important health and safety decisions with a qualified medical professional.

Where Decis is heading

How far can your records take you?

Today Decis compares your past records to help with today's choice. The more records you have, the closer they come to a model of you, and the goal is to use that model to judge a change before you make it.

  1. 01Now

    Gather

    Sleep, training, meals, calendar, and AI work records on one timeline.

  2. 02Now

    Compare

    How days like that differed from days that were not, with the sample size and limits shown.

  3. 03Now

    Look ahead

    Find the past days that looked like today and check in Ask how the day after went.

  4. 04Now

    Try it and check

    After changing a habit, compare before and after to see whether it worked for you.

  5. 05Next

    Judge it before you change it

    Run the options through a model built from your own records and compare the outcomes first. This is what people call a digital twin, and it is the next step Decis is working toward.

Getting started

It starts with your meal logs.

If Apple Health already holds your nutrition records, connect them as they are. If not, start logging in the Decis iOS app.

  1. Install the iOS app and connect

    After signing up, follow the connection screen to install the Decis iOS app and sign in with the same account. Your Apple Health nutrition, sleep, and heart-rate records connect.

  2. Log meals and caffeine

    Log a meal in the app and its nutrients are analyzed and placed on your timeline. Decis also reads nutrition records other apps saved to Apple Health.

  3. Ask about a change

    Ask about the records before and after a habit you changed, such as late dinners, a caffeine cutoff, or your fasting window.

Start free

Check your meal logs together with that night's sleep.

No credit card required. The Free plan includes 25 questions each month.

Connect your meal records freeView pricing
Answers that cannot reach a conclusion because evidence is insufficient do not use your allowance.