【Change How Old You Look】Can 16-Hour Fasting Really Turn Back the Clock? How Reducing Inflammation Can Rejuvenate Your Skin and Body

“Lately, I feel like my skin has been losing its firmness…”

“Ever since I hit my 40s, it’s been harder to shake off fatigue…”

A lot of people actually feel this way.

But before you give up and decide “it’s just aging, nothing I can do,” there’s something I’d like you to hold on and consider.

In fact, recent research has been making it increasingly clear that “chronic inflammation” quietly smoldering inside your body is a major cause of skin aging, fatigue, and feeling unwell.

And 16-hour fasting (intermittent fasting) has the power to effectively calm this chronic inflammation and rejuvenate your body.

In this article, I’ll explain in simple terms how fasting resets inflammation and rejuvenates your skin and body, drawing on scientific evidence and my own experience.

I’ll be honest with you, from the perspective of someone who’s been fasting for 2 years and has read more than 30 books on the subject.

That Vague “Something’s Off” Feeling in Your 40s Was Caused by Chronic Inflammation

Once you hit your 40s, you start to feel “a bit off” in different parts of your body more and more often, even though you’re not actually sick.

You tire easily, your skin looks dull, your body feels heavy, you can’t stay focused…

What lies behind symptoms like these is “chronic inflammation.”

What Is Chronic Inflammation?

When you hear “inflammation,” you probably picture a wound turning red and swollen, or running a fever when you catch a cold.

That’s called “acute inflammation,” and it’s your body’s defense response for fighting off bacteria and viruses.

Acute inflammation is like fire trucks rushing in to put out a fire that’s broken out in your house all at once.

Chronic inflammation, on the other hand, is completely different.

It’s a state where inflammation keeps going inside your body bit by bit, slowly, at a level you can’t see.

To put it another way, it’s like a small fire smoldering behind the walls of your house, gradually damaging the beams and walls without you noticing.

Because it doesn’t cause a fever or swelling, its biggest defining feature is that it’s hard for you to notice.

Research has shown that when this chronic inflammation goes on for a long time, it becomes a cause of all kinds of problems, including skin aging, fatigue, weakened immunity, weight gain, and low mood.

Why People Today Are Prone to Inflammation

So why are people today so prone to chronic inflammation?

One of the big causes is “diet.”

When you eat a lot of processed foods, sugar, and refined carbohydrates, your blood sugar shoots up and your body releases a large amount of insulin.

When this cycle repeats, substances that promote inflammation in the body (inflammatory cytokines) tend to increase.

On top of that, lack of sleep, chronic stress, and lack of exercise are also major factors that make inflammation worse.

Modern lifestyles are full of things that trigger inflammation.

A lifestyle of putting something in your mouth from morning to night also robs your body of time to rest and keeps the embers of inflammation smoldering.

Actually, until I hit my 40s, I didn’t pay much attention to what I ate either.

I lived on convenience store food every day, ate dinner late, and couldn’t go without sweets, and looking back now, those eating habits were a fast track to chronic inflammation.

Back then, “feeling heavy from the moment I woke up” and “getting sleepy in the early afternoon” were normal for me, and I thought it was just aging.

How 16-Hour Fasting Resets Chronic Inflammation

So let’s look at how 16-hour fasting actually reduces chronic inflammation.

Fasting calms inflammation in the body through several different pathways.

Hungry Time Switches On Autophagy

During a fast, about 12 to 16 hours after your last meal, a phenomenon called “autophagy (self-eating)” takes place in your body.

Autophagy is a process in which cells break down and recycle old parts and abnormal proteins; in other words, it’s a “deep clean inside your cells.”

This deep clean removes the substances that trigger inflammation, which is thought to improve chronic inflammation.

It’s a mechanism that gained attention through the research of Professor Yoshinori Ohsumi, who won the Nobel Prize in Physiology or Medicine in 2016, and researchers around the world are still studying it today.

I explain how autophagy works in detail in the link between autophagy and 16-hour fasting.

Ketones Flip the Anti-Inflammatory Switch

As a fast continues, your liver produces substances called “ketones.”

Ketones are an energy source that takes the place of glucose, powering the cells of your brain and body.

And recent research has found that ketones have a direct effect in suppressing inflammation.

In particular, it’s been shown that a ketone called “beta-hydroxybutyrate (BHB)” suppresses the activity of NLRP3, a protein involved in inflammation.

NLRP3 is a protein that acts like a “fire alarm” for inflammation in the body.

Your body can’t rest if the alarm keeps ringing, so you could say the role of ketones is to calm it down.

Lower Insulin Helps Inflammation Settle Down

Since you’re not eating during a fast, your blood sugar stabilizes and insulin release is held in check.

Insulin is a necessary hormone, but it’s known that when it stays high all the time, it promotes inflammation.

When fasting lowers your insulin level, the release of inflammatory cytokines also decreases, making it easier for inflammation throughout your body to improve.

With these three mechanisms working together, fasting functions as a “reset switch for inflammation in your body.”

Even if each effect on its own is small, picture the smoldering embers gradually getting smaller as you repeat 16 hours of hunger every day.

The Rejuvenating Effects on Your Skin and Body You Can Feel from Fasting

For those of you wondering, “So what changes actually happen when inflammation goes down?”, here’s a detailed look at the rejuvenating effects you can feel from fasting.

Your Skin’s Firmness and Clarity Come Back

What supports your skin’s firmness and elasticity is a protein called collagen.

You could think of collagen as something like the springs in a bed, pushing your skin up from the inside.

Chronic inflammation increases the enzymes that break down collagen in your skin, robbing it of firmness and elasticity.

When fasting calms inflammation, less collagen gets broken down, and your skin gradually becomes plumper.

Also, because your blood sugar stabilizes during a fast, a phenomenon called “glycation” becomes less likely to happen.

Glycation is an aging reaction in which excess sugar binds to proteins, turning your skin yellowish and increasing wrinkles.

When you cook a pancake, the surface turns golden brown, and that’s also a kind of glycation, where sugar and protein bind together.

When fasting lowers your blood sugar, glycation is also held back, which is said to lead to less dullness and clearer skin.

Chronic Fatigue Becomes Easier to Shake Off

When chronic inflammation continues, your body ends up in a state where it’s as if it’s always “ready for battle.”

Because of that, your energy keeps getting used up on dealing with inflammation, and you easily end up in a state where “I’m still tired even after resting.”

When fasting calms inflammation, less energy is wasted, and your body can focus on its natural recovery.

This is thought to be why so many people feel that “my body feels so much lighter when I wake up in the morning.”

What surprised me most after I started fasting was this change in “how light my body feels in the morning.”

Before fasting, I’d hit snooze over and over every morning before I finally got up, but about 1 to 2 months after I started fasting, I began waking up feeling refreshed first thing in the morning.

My skin started changing too, and I was really happy when my wife said, “Your complexion looks really good lately.”

Your Gut Environment Improves and Your Immunity Gets a Boost

Chronic inflammation disrupts your immune system, creating a state where your body keeps fighting things it doesn’t need to.

When fasting calms inflammation, your immune cells can go back to their proper job, and you may catch colds less often or find your allergy symptoms easing.

Also, since no food is going into your gut during a fast, your gut gets time to rest.

Your gut is like a factory that works nonstop, and it needs time now and then to stop the line for an inspection.

A healthier gut environment is said to lead to better immunity and further improvement in inflammation.

Body Changes That Support Rejuvenation, and Caring for Your Skin

Growth Hormone and Changes in Your Body Shape

Hungry time is also when growth hormone, which is involved in repairing the body, is released more easily.

Growth hormone is like your “body’s maintenance crew,” a hormone that helps repair your skin, muscles, and bones.

I explain this in detail in how hunger triggers the release of growth hormone, so be sure to read that too.

What’s more, because your eating time is limited, your daily calorie intake tends to drop, so you can also expect your belly to get trimmer.

When your body shape improves, your posture and movements feel lighter too, which also helps you look more youthful.

Reduce Visceral Fat to Shrink a Source of Inflammation

The visceral fat that builds up around your belly isn’t just stored energy.

It’s said that when too much visceral fat builds up, it tends to release substances that promote inflammation.

In other words, visceral fat can also become a “source” that generates the sparks of inflammation.

When 16-hour fasting increases the time you spend using fat for energy, it helps shrink this source little by little.

For the changes you’re likely to feel in about 2 weeks, also take a look at the changes after 2 weeks of 16-hour fasting.

Changes in Your Skin Come After “Changes on the Inside”

Your skin is like a mirror that reflects what’s going on inside your body.

Inner changes like calmer inflammation, more stable blood sugar, and better sleep quality build up and gradually show up in your skin.

If you’re starting fasting for your skin, taking photos to keep a record will make it easier to notice even small changes.

Combine It with Care from the Outside

16-hour fasting is a way to improve your skin from the inside, but care from the outside is just as important.

Diet and Lifestyle Tips to Maximize the Rejuvenating Effects of Fasting

To get the most out of fasting, how you spend the time outside your fast matters too.

Even if you go to the trouble of resetting the inflammation in your body, if you keep eating things that trigger inflammation during your eating time, the benefits get cut in half.

Don’t Increase Inflammation with Your First Meal After a Fast

Your first meal after a fast ends (your “break-fast”) is especially important.

If you jump straight into a meal that’s heavy to digest or that spikes your blood sugar, inflammation is more likely to flare up again.

It’s best to start with foods that are easy to digest and have anti-inflammatory effects.

As for the order you eat in, aiming for vegetables and mushrooms first, then protein, then rice or bread, makes it easier to prevent blood sugar spikes.

Cut Back on Foods That Easily Spark Inflammation

Sweet breads, packaged snacks, soft drinks, fried foods, and processed meats are convenient and tasty, but they make your blood sugar spike or contain a lot of oxidized oil.

These are like pouring oil on the smoldering embers of inflammation.

You don’t need to give them up completely, but just changing them from “every day” to “an occasional treat” greatly reduces the burden on your body.

Protein is the building block of collagen in your skin, your muscles, and your hair, so also make a point of including eggs, fish, meat, or soy foods at every meal.

Better Sleep Quality Doubles the Rejuvenating Effects of Fasting

Fasting and sleep are both deeply involved in repairing and regenerating your body.

During deep sleep, growth hormone is released and your skin and muscles get repaired.

If you sleep while the inflammation in your body has been calmed by fasting, this repair effect is likely to be even stronger.

16-hour fasting where you finish dinner early (by 7 or 8 p.m.) naturally secures fasting time while you sleep, so it also helps improve your sleep quality.

Cutting back on your phone and computer before bed and sleeping in a dark room are also important ways to get deep sleep.

Boost the Anti-Inflammatory Effects of Fasting Further with Light Exercise

Intense exercise can actually trigger inflammation, but light aerobic exercise has anti-inflammatory effects.

Light walking, stretching, or yoga while fasting is effective for reducing inflammation even more and speeding up rejuvenation.

There are also research findings showing that just walking 20 to 30 minutes a day has a big effect on improving chronic inflammation.

Even if you’re “not into exercise,” just a short stroll around the neighborhood is plenty.

Things to Watch Out for When Aiming to Rejuvenate with 16-Hour Fasting

Overdoing It Can Backfire

Rushing to get younger by repeatedly fasting for 24 hours or more, or severely restricting what you eat during your eating window, isn’t recommended.

When you don’t get enough nutrients, your skin can get dry, your hair can get brittle, and you can lose muscle, which may actually make you look older.

If you get dizziness, severe fatigue, or shaky hands, don’t push yourself; have some food and fluids.

Watch Out for Not Getting Enough Fluids and Nutrients

While fasting, you get less water from food, so it’s easy to become dehydrated without realizing it.

Not getting enough fluids can also cause dry skin, headaches, and constipation.

Make a point of drinking water or tea a little at a time, often, before you get thirsty.

Also, because your eating window is shorter, it’s easier to fall short on vitamins, minerals, and protein.

Combine vegetables, fruit, fish, soy foods, and more to make sure your skin gets the building blocks it needs.

Don’t Let Stress Build Up

Letting stress pile up in the name of getting younger would defeat the whole purpose.

Chronic stress is also a factor that makes inflammation worse, so it’s important to keep going with some breathing room, for example by shortening your fast on tough days.

Having your own ways to relax, like deep breathing, a warm (not hot) bath, or time for your hobbies, also makes fasting easier to stick with.

People Who Should Talk to a Doctor Before Starting

If any of the following apply to you, don’t start on your own; talk to your doctor first.

Especially if you take medication to lower your blood sugar, skipping meals could make your blood sugar drop dangerously low.

If you have any concerns about your health, talk with your doctor and start with a fasting time that feels comfortable.

If you keep notes on how you feel while fasting and share them with your doctor at your appointment, the consultation will go more smoothly.

Not pushing yourself and listening to your body as you go is the surest shortcut to getting younger.

Frequently Asked Questions About Rejuvenation with 16-Hour Fasting

Start 16-Hour Fasting Today and Get Back the Youthfulness of Your Skin and Body

Many of you may be thinking, “I’d like to try it, but I’m worried I won’t be able to keep it up…”

But there’s no need to overthink 16-hour fasting.

For example, if you finish eating at 9 p.m., the time you’re asleep until the next morning counts toward your fast,
so the only time you actually have to consciously set aside as “non-eating time” is a few hours in the morning.

3 Steps So Even Beginners Can Start Comfortably

At every stage, aim for balanced meals centered on vegetables and protein during your eating time.

Support to Make Fasting Easier to Stick With

If you’re thinking, “The hunger is so hard that I can’t keep it up…”, one option is to make smart use of supplements.

Actually, one of the big reasons I was able to stick with fasting for 3 months was discovering a supplement called Unicity’s Unimate and Balance.

It made hunger during my fasts a lot easier, and I was able to stay focused at work too.

Honestly, it’s not cheap, but I think it was worth more than the price.

If you’re thinking, “I want to start fasting, but I’m worried about the hunger,” be sure to check it out.

I’ve summarized the basics of 16-hour fasting in the complete guide to intermittent fasting.

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