Studies & Research

Last Updated: 13th of November, 2025

Why fasting, consistency, and small choices can change the way your body — and mind — feel.

The short version

When you give your body regular breaks from eating, it gets a chance to do what it was designed to do: repair, rebalance, and renew.
This is the foundation of intermittent fasting — and why so many people feel clearer, lighter, and more in control after a few weeks.

But fasting isn’t magic. It’s science. Here’s what’s happening under the hood.

1. Your metabolism switches fuel

When you’re not eating, your body gradually shifts from burning glucose (sugar) to burning fat.
This metabolic flexibility allows your body to tap into stored energy — the fat that’s been waiting to be used.

As insulin levels drop, fat cells release energy more easily.
The result? More stable energy, fewer crashes, and a natural sense of appetite control.
(Sources: NIH, Harvard Health Publishing)

2. Your cells start a cleanup process

After a few hours of fasting, your body activates autophagy — literally meaning “self-eating.”
It’s how your cells recycle old or damaged components and make room for new ones.
Think of it as your body’s built-in detox system — one that operates on biology, not juice cleanses.
(Source: NIH)

3. Your hormones rebalance

Fasting gently increases growth hormone (GH) and norepinephrine, helping preserve lean muscle and slightly increase calorie burn.
Meanwhile, insulin decreases, improving blood sugar control and making it easier for your body to access stored fat.

That’s why people often describe fasting as feeling “lighter” — not just in weight, but in energy.

4. Your brain gets a boost

During fasting, the brain produces more BDNF (Brain-Derived Neurotrophic Factor) — a molecule that supports learning, mood, and memory.
In simple terms: your brain becomes more resilient to stress.
It’s one reason why many users report sharper focus and calmer moods during their fasting windows.
(Source: NIH)

5. Your habits begin to align

Science doesn’t stop at biology — it’s also about behavior.
At WeightBuddy, we’re inspired by research from Stanford’s Behavior Design Lab, which shows that lasting change comes from tiny, consistent wins.

Each time you track a fast, get a reminder, or celebrate progress with Buddy, you’re reinforcing a loop of self-trust — the real key to sustainable health.
(Source: NIH, BJ Fogg, Tiny Habits, 2020)

6. Why “kind fasting” matters

Strict, all-or-nothing approaches usually fail because they ignore stress, sleep, and emotion.
That’s why WeightBuddy encourages flexibility — adjusting fasting windows around real life, not the other way around.
Science shows that self-compassion improves adherence and long-term success far more than rigid rules ever could.
(Source: NIH)

The bottom line

Fasting works because it respects your biology.
Consistency works because it respects your psychology.
WeightBuddy helps you connect both — one small, kind choice at a time.

More links to studies:
‍
National Libray of Medicine - Intermittent Fasting and weight loss‍‍
National Library of Medicine - Intermittent fasting and protein pacing are superior
BBC - The benefits of intermittent fasting the right way