Intermittent Fasting×Mindful Eating

Fasting and eating, finally in one app.

Track your fasts, log your meals, and see how they affect each other — all in one place.

Available on iOS and Android

Scroll to explore

Fasting apps track time. Food apps track calories. Atomic Fast connects both — so your meals inform your fast, and your fast informs your meals.

Every fast is a journey.Here's what happens inside your body.

Scroll to see what your body goes through — from digesting your last meal to burning fat to deep cellular repair.

0h 00m

Digesting

0–4 hours

Digesting

Your body is still processing your last meal. Insulin is elevated as nutrients are converted into energy.

4–8 hours

Blood Sugar Normalizing

Blood sugar is settling and insulin is dropping. Your body is starting to shift away from using food as its main fuel.

8–12 hours

Glycogen Depletion

Your stored energy reserves are running low. Your body is getting ready to switch to burning fat — the crossover point.

12–16 hours

Fat Burning

Lipolysis is now dominant. Your body is actively breaking down stored fat into ketones, and growth hormone spikes to preserve lean tissue.

16–24 hours

Deep Ketosis

Ketone levels are high, fueling your brain and body. You may notice sharper focus and steady energy as cellular repair kicks in.

24+ hours

Autophagy

Peak cellular recycling. Damaged proteins and organelles are being broken down and recycled. This is the deepest level of cellular rejuvenation.

0h 00m

Digesting

0–4 hours

Digesting

Your body is still processing your last meal. Insulin is elevated as nutrients are converted into energy.

4–8 hours

Blood Sugar Normalizing

Blood sugar is settling and insulin is dropping. Your body is starting to shift away from using food as its main fuel.

8–12 hours

Glycogen Depletion

Your stored energy reserves are running low. Your body is getting ready to switch to burning fat — the crossover point.

12–16 hours

Fat Burning

Lipolysis is now dominant. Your body is actively breaking down stored fat into ketones, and growth hormone spikes to preserve lean tissue.

16–24 hours

Deep Ketosis

Ketone levels are high, fueling your brain and body. You may notice sharper focus and steady energy as cellular repair kicks in.

24+ hours

Autophagy

Peak cellular recycling. Damaged proteins and organelles are being broken down and recycled. This is the deepest level of cellular rejuvenation.

AI-First Smart Meal Logging

Log a meal in under 10 seconds.

No searching. No scrolling. No guessing.

Atomic Fast expanded logging sheet showing 6 ways to log: Scan Food, Describe Meal, Water, Scan Label, Upload Photo, My Meals, Scan Barcode

Many ways to log

Six ways to log. All under 10 seconds.

Snap a photo, describe in words, scan a barcode or nutrition label, upload from gallery, or pick from saved meals — AI handles the rest.

SNAP IT

Point your camera. AI identifies everything.

Point your camera at any plate. AI identifies every item and breaks down the full nutrition — in seconds.

chicken rice salad

DESCRIBE IT

Type 'chicken rice and salad' — AI does the rest.

Just type what you ate in your own words. AI figures out the portions, nutrition, and everything else.

SCAN IT

Scan any package. Nutrition imported instantly.

Scan any barcode to pull nutrition from 2.5M+ products. Or snap the nutrition label and AI reads it for you.

“Spend your time eating, not logging.”

Fasting + Food

Fasting is half the equation.

No other app connects both sides. Your meals make your fasts smarter. Your fasts make your meals smarter.

Nutrition

Fasting

What you eat

Track what you eat — calories, macros, and more.

Weekly calorie rings, daily macro breakdown, water intake, nutrient tracking, and AI-powered metabolic insights on every meal you log.

Weekly calorie tracking

Macro breakdown: P · C · F

AI meal insights per food

How you fast

Your fast and your food — in one place.

22 hours deep in ketosis? The app knows. Log a meal right from the fasting view — it adjusts your timeline, goals, and recommendations automatically.

Atomic Fast today view showing fasting timer at 22h 13m in ketosis with meal logging sheet

22h 08m — deep in ketosis

Metabolic phase education

Adaptive daily fasting goals

See what each meal does to your fast.

How long until you’re back to burning fat? When will digestion finish? Atomic Fast shows you.

Fat Burning Delay

~7h

Digestion Complete

5:11 PM

Glycemic Load

Low

Fat Burning Delay

~7h

Digestion Complete

5:11 PM

Glycemic Load

Low

“Log a meal during a fast — your timeline, goals, and recommendations update automatically.”

Smart Insights

“Is this working?”

Atomic Fast finds patterns across your meals, fasts, sleep, and activity — then tells you what’s actually making a difference.

Atomic Insights· Last 14 Days

Fasting Day Calories

You consume 256 more calories on fasting days — your body is overcompensating. Splitting your eating window into 2 meals instead of 1 large one could help.

FAST DAYS2214

NON-FAST1958

Sleep & Fasting Harmony

Your sleep quality holds steady at 95% on fasting days. 16:8 isn't disrupting your recovery — you're in a sustainable rhythm.

95%

QUALITY

Stable

7.5h

AVG SLEEP

Higher Meal Impact

Your time to fat burn jumped from 4.9h to 6.1h this week. Heavier carbs at dinner are delaying ketosis — try shifting carbs to your first meal.

4.9h

LAST WEEK

+1.2h

6.1h

THIS WEEK

Late Eating & Heart Rate

Your resting heart rate spikes 8 bpm higher on nights you eat after 9 PM. Late meals are keeping your metabolism elevated when it should be winding down.

EAT BY 7PM

+8 bpm

EAT AFTER 9PM

Fewer Meals, Same Satisfaction

You eat 1.3 fewer meals on fasting days but maintain similar calorie intake. Your meals are more nutrient-dense — quality over quantity.

Fewer, fuller meals can be more satisfying

Window Discipline

You hit your eating window 4 out of 8 days — but on the days you did, your avg fast was 17.2h. Consistency is the missing piece.

Try timing meals with your fast

Calorie Variation

Your intake swings ±818 cal day-to-day (avg 2086). This kind of variance can stall progress — even when your average is on target.

Try keeping daily calories consistent

Your body has the answers.

Your health data from Apple Health — sleep, heart rate, activity, and more — becomes fasting intelligence.

Health & Readiness screen showing Recovery score of 75/Good with 8 health signals analyzed from HealthKit

Recovery & Readiness

Strong HRV, calm heart rate — 8 of 10 signals analyzed

Heart Rate Variability

40ms

Above Baseline

Resting Heart Rate

64 bpm

Very Calm

Sleep Duration

7h 42m

Optimal

Activity Load

45 min

Active

Daylight Exposure

32 min

Moderate

Respiratory Rate

12.7 br/min

Calm Breathing

Correlations you can't see yourself.

Your health data becomes fasting intelligence.

“Ending eating by 7 PM drops your sleeping heart rate by 4 bpm”

“On high-recovery days you're 30% more likely to hit your fasting goal”

“30+ minutes of daylight correlates with hitting your targets”

7 engines that learn from your data

Fasting Patterns

Meal Impact

Break-Fast Score

Readiness

Health Patterns

Fasting × Nutrition

Nutrition Trends

Smart Nudges

Phase milestones

"Fat burning activated" — right when it happens

Smart hydration

Electrolyte tips that adapt to your fast

Diet-aware timing

Nudges based on what you ate, not just the clock

“Your data, analyzed on your device. No cloud dependency. No generic advice.”

Privacy

Your data stays on your device.

Atomic Fast analyzes everything locally. No cloud processing for your personal data. Backups go where you choose — iCloud or Google Drive, encrypted and under your control.

On-device analysis

Your data is processed locally

Cloud Backup & Sync

iCloud and Google Drive — encrypted, your choice

Personal, not generic

Insights built from your patterns

Start understanding your fasting and eating

Download free on iOS and Android.

Download on theApp Store

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