Guided intermittent fasting

Less belly fat, more energy, no calorie counting

You pick the schedule and Ayuname walks you through every phase. Most people notice less bloating, fewer cravings, and no more afternoon crash.

16:8Best place to start
6 plansFrom 16:8 to 72h
$0Free, no ads
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Less belly fat, more energy, no calorie counting
Sound familiar?
I bloat after every meal and drag myself through the afternoon
Less belly fat, no counting
I've done a thousand diets and always end up back at square one
No more 5 p.m. crash
I snack between meals even when I'm not actually hungry
Fewer cravings, less snacking
What you will notice

What you get out of it

This is what changes in your day to day when you give your body well-guided hours without food.

Less belly fat, no counting

Your jeans fit better and you bloat less, just by changing when you eat.

Why:With insulin low for hours, your body taps into stored fat.

No more 5 p.m. crash

Steady energy all afternoon, without needing a coffee or something sweet to get through it.

Why:No blood sugar spike after eating means no sharp drop afterward.

Fewer cravings, less snacking

You stop thinking about food all day. You eat when it's time, and you eat calmer.

Why:Your hunger hormone adjusts to your new schedule within a few days.

Sleep through the night

No heavy late-night digestion, so you wake up less and feel more rested.

Why:An earlier dinner lets your body repair instead of digest while you sleep.

A clear head in the morning

Many people notice sharper focus during fasting hours: less fog, more clarity.

Why:After 12-14h your body makes ketones, a steady fuel for your brain.

Better bloodwork over time

Studies link fasting with better blood sugar, triglycerides, and blood pressure.

Why:Fewer hours eating improves how you handle sugar and fats.
SCIENCE · PHASE BY PHASE

What happens in your body, hour by hour

The app tells you the moment you enter each phase. No more waiting around to "see if it works."

4h
Digestion
Running on your last meal
0-4hDigestion

Running on your last meal

Business as usual. Your body is using what you just ate. Good time to start the timer.

4-8hSteady blood sugar

No spikes, no crash

Insulin drops. Calm energy, without the post-meal food coma.

8-12hFuel switch

You start tapping your reserves

Hunger may hit in waves. It passes in minutes with water or a black coffee.

12-14hFat burning

Your body uses fat for energy

Glycogen runs out. Many people notice less bloating and a clearer head.

14-16hLight ketosis

Steady energy and focus

Ketones show up. Hunger usually settles and focusing takes less effort.

16h+Early autophagy

Your body recycles and repairs

Goal hit. Break your fast with protein and veggies, and add a day to your streak.

Your progress

What to expect, week by week

Week 1

Your body adapts. Mid-morning hunger shows up and passes sooner each day.

Weeks 2-3

Less bloating, less snacking, and afternoons without the usual crash.

Month 1

Your clothes fit better and fasting is routine now, not an effort.

Month 3

Habit locked in. Good time to review your bloodwork with your doctor.

What the science saysAyuname: free intermittent fasting app, no ads

Intermittent fasting alternates periods without food and eating windows; the most studied daily form is time-restricted eating (e.g. 16:8). It may help you eat less without counting calories and improve some cardiometabolic markers, though in trials it does not outperform a calorie-restricted diet. It is not suitable during pregnancy, with eating disorders, or with medicated diabetes without medical supervision.

  • In the TREAT trial (116 adults, 12 weeks), 16:8 with no other changes did not produce more weight loss than three meals at set times. [3]
  • In 139 people with obesity over 12 months, eating between 8 a.m. and 4 p.m. plus a calorie-restricted diet did not beat the diet alone (-8.0 vs -6.3 kg). [4]
  • The most studied forms are alternate-day fasting, the 5:2 diet, and time-restricted eating. [2]
Frequently asked questions

Frequently asked questions

What is intermittent fasting?
It's alternating hours when you eat with hours when you don't. It doesn't tell you what to eat, only when. The most popular version is 16:8: 16 hours without food, night included, and an 8-hour window for your meals.
What can I have while fasting?
Water, black coffee, tea, and unsweetened herbal teas. A pinch of salt in your water helps if you feel a little weak. Milk, juice, and sweetened drinks break your fast.
Am I going to be hungry?
A little, the first few days. Hunger comes in waves and passes in minutes. Ayuname alerts you at each phase so you know what's going on. Within a week or two, most people notice hunger settles down.
Is the app really free?
Yes. Ayuname is free and ad-free on iOS and Android. It includes 16:8, 18:6, OMAD, 24h, 48h, and 72h plans, phase alerts, history, streaks, an AI coach, and photo meal logging.
Who shouldn't fast?
Fasting isn't recommended during pregnancy or breastfeeding, for anyone under 18, if you're underweight, or if you've had an eating disorder. If you take medication, especially for diabetes or blood pressure, talk to your doctor first.
Scientific sources (4)
  1. Effects of Intermittent Fasting on Health, Aging, and Disease. New England Journal of Medicine, 2019.
  2. Clinical application of intermittent fasting for weight loss: progress and future directions. Nature Reviews Endocrinology, 2022.
  3. Effects of Time-Restricted Eating on Weight Loss and Other Metabolic Parameters in Women and Men With Overweight and Obesity. JAMA Internal Medicine, 2020.
  4. Calorie Restriction with or without Time-Restricted Eating in Weight Loss. New England Journal of Medicine, 2022.
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Learn to fast well with our articles

Fasting guides

See all guides →
HealthIntermittent fasting side effects (and how to avoid them)
ProtocolsWater fasting: what it is, benefits, and the real risks
GuidesHow to start 16/8 intermittent fasting (beginner's guide)

Start today. Free.

Download the app and start your first guided fast.

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Your first crash-free afternoon starts today

Download the app and start your first guided fast.

Download on theApp Store Get it onGoogle Play

Educational information based on studies on intermittent fasting. Results vary from person to person. This is not medical advice.