Intermittent-Fasting Results: What’s Possible in 30 Days?

Written and medically reviewed by Katya Meyers, RD

Many of us have attempted diets that promise rapid results, only to find that they aren’t sustainable or lead to a yo-yo effect. But with intermittent fasting, you get results by focusing on when — instead of what — you eat.

With IF (intermittent fasting), you eat during a preset eating window and fast for the remainder of the day. It’s a science-based strategy that aligns with the way humans used to eat. In prehistoric times, humans were nomadic hunters and gatherers who thrived on extended periods, often days, of fasting between meals.

The concept of permanent settlements and eating three meals a day came only with the emergence of agriculture. Moving into modern times, there’s no question that we’re much more sedentary than we used to be; we spend more time sitting and snacking than working or playing outdoors. 

Undoubtedly, the increase in calories and decrease in physical activity are leading contributors to the obesity and chronic-disease epidemic in our modern society — but there is hope. Following an intermittent-fasting plan for 30 days could help you lose weight, and sticking to it long-term could even reverse some of these adverse effects.

How Long Does It Take to See Intermittent-Fasting Results?

If you’re just getting started with intermittent fasting, you may be wondering how long it takes to see results. Many people begin to notice intermittent-fasting results, such as improved gut health, focus, and energy, in just a few days. 

If your goal is weight loss, you may begin to notice changes in your body in as little as ten days, with noticeable weight loss in the first month. But many factors come into play here, such as your physical health, lifestyle, and the duration of your fasting window.

The intermittent-fasting schedule you choose can impact the speed of your results. For example, you might eat during an 8-hour window each day and fast for the remaining 16, or you might eat during a 6-hour window and fast for 18. Other plans involve eating only once a day (OMAD) and alternate-day fasting.

Longer fasts typically produce faster weight-loss results. That’s because when you’re eating three meals a day (plus snacks) and not burning off excess calories through exercise, your body runs on those calories instead of burning through your fat stores. 

But after about 16 hours of fasting, the body uses up its sugar stores and begins to burn fat, a process called metabolic switching. Time-restricted eating triggers a cascade of positive effects in the body, including weight loss, increased energy, improved mental clarity, and more.

30-Day Intermittent Fasting Results for Weight Loss

Men and women often experience an average weight loss of 1–2 pounds per week with intermittent fasting. That means you could lose 4–8 pounds in 30 days. Furthermore, studies show that typical weight loss with intermittent fasting is 7–11 pounds over the course of ten weeks.

Of course, your intermittent-fasting weight-loss results will vary depending on your starting weight, the types of food you eat, and your activity level. For example, if you pair intermittent fasting with healthy eating and move your body regularly, you’ll experience faster weight loss.

That being said, it’s healthier to lose weight at a slow, steady rate. You’re also much more likely to stick with your plan and keep the weight long term if you don’t try to rush the process. In other words, don’t be tempted to restrict your calorie intake too much or overdo it with intense exercise.

What Are the Long-Term Results of Intermittent Fasting?

Losing weight quickly may be the primary motivator for many who try intermittent fasting, but don’t forget that sustainable results and overall health are more important than losing weight fast. Let’s explore the results you can expect from intermittent fasting over the long term.

#1) Healthy, Sustainable Weight Loss

Sure, quick results are nice, but sustainable weight loss is the ultimate goal for overall health and longevity, and intermittent fasting is an excellent strategy for long-term weight loss. Eating only during a set period naturally leads to consuming fewer calories. 

IF also results in increased metabolism, fat loss, and improved insulin sensitivity. Insulin levels decrease when we refrain from snacking in between meals. This process allows stored sugars in our fat cells to be released, which helps in losing weight.

#2) Improved Hormone, Cellular, and Gene Function

Intermittent fasting influences your hormone levels to make stored body fat accessible for energy, facilitating crucial cellular-repair processes. Here are some examples of the changes that occur in your body during a fast:

  • Insulin: Insulin levels in the blood drop significantly during a fast, which promotes fat burning.
  • Human Growth Hormone (HGH): The levels of HGH in your blood increase dramatically, further promoting fat burning. Higher levels of HGH also promote muscle gain and prevent muscle loss.
  • Cellular Repair and Regeneration: An important cellular-waste-removal process called autophagy is initiated. This process removes waste material from your cells and recycles it to build new cells. Increased autophagy could help protect against premature aging and diseases like cancer and Alzheimer’s.
  • Gene Expression: There are several beneficial changes in specific molecules and genes related to longevity.

#3) Reduced Inflammation and Oxidative Stress

Inflammation and oxidative stress are two key drivers of aging and chronic disease. Studies show that long-term intermittent fasting can result in less oxidative stress and inflammation throughout the body, helping in the fight against premature aging, heart disease, and more.

#4) Improved Brain Health

Studies show that intermittent fasting promotes the growth of new neurons in the brain, improving brain function and helping to protect it from damage.

Intermittent fasting also increases levels of a brain hormone called brain-derived neurotrophic Factor (BDNF). BDNF has antidepressant effects, helps repair brain damage, and is essential for learning and memory.

#5) May Extend Your Lifespan

Perhaps one of the most exciting long-term results of intermittent fasting is its potential to prolong your lifespan. Animal studies show intermittent fasting could extend lifespan similarly to continuous calorie restriction.

It may also delay the development of conditions like fatty-liver disease and certain cancers. Although research in this area is ongoing, given IF’s proven benefits for metabolism and overall health, it makes sense that it could help you live a longer, healthier life

Maximizing Your Intermittent-Fasting Results in the First Month and Beyond

Intermittent fasting produces impressive results on its own. Still, there are some things you can do to maximize your results even more.


If your overall health is good and your doctor has given you the OK to exercise, getting your body moving while intermittent fasting is a great way to maximize your results. It can help you progress through the metabolic stages more quickly, meaning you’ll burn more fat and achieve your goals more quickly while maintaining and building muscle.


It stands to reason that limiting your food intake also means reducing your intake of certain nutrients. You should feel free to take any vitamins that you normally take, but remember that some vitamins can make you feel nauseous on an empty stomach, so it’s best to take them during your eating window.

Replenishing your electrolytes during a fast can also help your body function optimally. Sodium prevents headaches and muscle spasms, while potassium supports heart function and optimal energy levels. Magnesium can also improve sleep and regulate muscle and nerve function.

You may also want to consider adding an L-tyrosine supplement to your daily routine. The brain uses tyrosine to make three important neurotransmitters: dopamine, norepinephrine, and adrenaline. Supplementing with L-tyrosine may improve your mental performance and help you regulate your moods while fasting. 

Meal Prep and Planning

To get the best results with intermittent fasting, you should eat a clean, healthy diet. Meal prepping and planning can help ensure you always have healthy foods on hand. It can also help you resist binge eating and junk food during your eating window. Creating a meal plan is an excellent way to monitor calorie intake so that you’re neither undereating nor overeating.

Will I See IF Results without Exercise?

You can still see intermittent-fasting results without exercise as long as you incorporate clean eating and an overall healthy lifestyle that includes getting enough sleep. That being said, you’ll see faster results and feel better if you try to incorporate some exercise or movement into your daily routine. Exercise is essential for mental and physical health, not just for weight loss. 

Reasons You May Not Be Seeing IF Results After 30 Days

There can be many reasons why you’re not losing weight on intermittent fasting. Here are some things to consider if you’re not seeing results after 30 days. 

You’re Not Consuming Enough Calories

It may seem counterproductive, but it’s essential to ensure you’re consuming enough calories during your eating window. If you’re not consuming enough calories, you’ll be more likely to snack between meals or binge during your next eating window.

More importantly, not consuming the calories your body needs could cause it to store more fat for the long term. When your body notices that you’re not getting enough food, it conserves energy and stores whatever it can as fat to ensure you have a reliable energy source when food isn’t available.

You’re Not Eating Enough Protein

Beginners who are new to intermittent fasting may notice that their meals aren’t carrying them from their fasting window to their eating window. This can make it challenging to stick to your schedule and may result in breaking your fast too early.

Including more lean protein in your meals can be a great solution, because protein can help you feel fuller for longer. And if you’re exercising regularly, protein is also essential for building muscle while you lose weight. 

You’re Eating the Wrong Types of Food

Many diets list foods you can and can’t eat, but that’s not how intermittent fasting works. Technically, you can eat whatever you want within your eating window, but that mindset can make it easy to slip into unhealthy eating habits.

Making unhealthy food choices will slow your intermittent-fasting results, as will binging on too many calories without burning them off through exercise. Sugary foods in particular can elevate your blood-sugar levels, reduce insulin sensitivity, and slow your progress. 

Eating a clean, minimally-processed diet will help you get the best results possible in the shortest amount of time. Avoid processed and sugary foods and keep your blood sugar in a normal range.

Your Fasting Period Is Too Short

To get the best results with intermittent fasting, your eating window should be significantly shorter than your fasting period. If the difference is only an hour or two, your weight loss will be negligible, and your progress will be slow.

While a 12:12 or 14:10 intermittent-fasting schedule can be a great place to start for beginners, working your way up to a 16:8 or 18:6 schedule will help you see more dramatic results in less time.

You’re Not Hydrating Enough

While intermittent fasting does restrict your meal times, it places no restrictions on drinking water and other calorie-free beverages, like unsweetened tea and black coffee, throughout the day. 

Drinking enough fluids can help you feel fuller and resist the urge to snack and overeat. Staying hydrated can also help you avoid headaches and fatigue while you fast.

You’re Breaking Your Fast Prematurely

Most of us are used to snacking between meals, so not consuming any food during your fasting period can be difficult when you’re first starting out. If this is a constant issue for you, your chosen fasting period may be too long for you right now. Consider reducing your fasting period by an hour or two and gradually increasing it as time passes. 

This will give your body time to adjust and help you avoid breaking your fast too soon. The best IF protocol for weight loss is one you can stick with, so be prepared to make gradual changes as you find the right regimen for you.

Conclusion: Fasting Can Give You Results in 30 Days

From shedding excess weight to boosting brain health and increasing longevity, intermittent fasting has proven its potential to revolutionize the way we approach our health goals. However, it’s essential to remember that intermittent fasting is not a one-size-fits-all solution, so listen to your body and tailor your approach to suit your individual needs. For accelerated results, combine intermittent fasting with healthy eating, regular exercise, and positive lifestyle habits.

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Katya Meyers, RD
Posted in Health & Science

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