Last update: June 11, 2024

8 minute read

What is Intermittent Fasting?

Discover intermittent fasting, a lifestyle choice revolutionizing health and wellness. Explore how this dietary practice, focusing on timing over content, can optimize your well-being.

Stephanie Wright

By Stephanie Wright, RN, BSN

Edited by Dr. Dimitar Marinov, MD, MBA, PhD

Learn more about our editorial standards

Have you ever felt overwhelmed by the variety of diets and eating plans, each promising to be the key to optimal health and your dream physique? Let's press the pause button on the confusion and dive into a lifestyle choice that's been making waves in the health and wellness community - intermittent fasting.

Key takeaways

  • Intermittent fasting is an eating pattern where you alternate between eating and fasting periods
  • It can lead to weight loss, improved metabolic health, and potentially enhance brain function
  • Some people might experience hunger, fatigue, or irritability during fasting periods

    What is intermittent fasting?

    What is intermittent fasting? Intermittent fasting is a dietary practice that cycles between periods of eating and fasting, focusing more on when to eat rather than what to eat. When followed correctly, research suggests that this eating pattern can offer many health benefits, including weight management.

    Why is intermittent fasting popular?

    Intermittent fasting is trending big time - not just among fitness junkies but also among health-conscious peeps who want to switch up their lifestyle game. What makes it so popular? It's not just a fly-by-night fad but a return to our roots.

    Taking a cue from our ancestors

    According to Mark Mattson, a well-respected Johns Hopkins neuroscientist who's been delving into the science of intermittent fasting for the past 25 years, your body is biologically wired to go periods without food. Our ancestors were hunters and gatherers who evolved to survive, and dare we say, thrive in times of food scarcity.

    The modern lifestyle shift

    Fast forward to the present, and your lifestyle has dramatically changed. The convenience of 24/7 entertainment and the internet, your love for late-night Netflix binges, and the availability of food around the clock have significantly shifted your eating patterns.

    Consequently, we're moving less, snacking more, and piling up those extra calories—a recipe for health problems. Integrating intermittent fasting into your modern lifestyle may just be the reset button we need to combat these health challenges. It's all about taking back control of your body's natural rhythm and beating the unhealthy odds stacked against you.

    How does intermittent fasting work?

    At its core, intermittent fasting is a game of timing—it's about when to eat, not what to eat. But you might be wondering, how does it work? Mark Mattson hypothesizes it's a process he calls metabolic switching.

    The hypothesis of metabolic switching

    After a certain number of hours without food, your body’s carbohydrate stores start to deplete and your body starts using fat instead. This switch from burning mostly sugar to burning mostly fat is what Mark Mattson calls 'metabolic switching'.

    In short, he claims that intermittent fasting helps your body become a fat-burning machine. In reality, your body burns both carbs and fats pretty much all the time and switches towards predominantly burning fat every time you haven’t eaten for a few hours. Moreover, even 8 hours of an overnight fast have been shown to be sufficient in increasing ketone levels which are an indicator of “shifting” towards burning fat.

    The American eating pattern

    Most Americans tend to graze throughout the day, from breakfast through to late-night snacks. Without a substantial break from eating, you're likely to overeat and consume too many calories.

    Intermittent fasting offers a tool to restrict energy intake without counting calories. Instead, you restrict the time window you have for eating food. To reiterate, intermittent fasting is a simple yet powerful shift in eating patterns that could help manage your weight and support your overall health.

    VitaRx Tip

    Remember, it's not about starving yourself, it's about eating in a way that aligns with your body's physiological needs.

    What intermittent fasting plans can I try?

    Deciding to embark on the intermittent fasting journey is just the first step. The next one is choosing an intermittent fasting plan that suits you.

    Remember, like your favorite pair of jeans, it has to be the right fit for you to stick with it. Let's dive into some of the plans you could consider.

    16/8 Method

    This popular approach involves daily fasting for 16 hours and restricting your eating window to 8 hours. For most people, this usually means skipping breakfast and eating from noon to 8 p.m.

    Just remember, though, that one study found this plan doesn't guarantee weight loss over time, so it's essential to maintain a balanced diet during your eating hours and not overeat. Consuming too many calories for the day or the week will prevent you from losing weight regardless of the IF method.

    The 5:2 Approach

    The 5:2 approach is another well-loved intermittent fasting plan. It involves eating regularly for five days of the week and limiting yourself to one 500-600 calorie meal for the other two days. It's like treating yourself to a mini-break from normal eating twice a week.

    Just remember, these plans aren't set in stone. Feel free to tweak them until you find the right fit for you. Intermittent fasting is about tailoring your eating schedule to your lifestyle, not the other way around.

    What are the health benefits of intermittent fasting?

    You've probably heard a lot about intermittent fasting benefits by now. From boosting mental performance to enhancing heart health, it seems like the wonders of this eating plan never end. Let's unpack these benefits.

    • Boosted working memory
    • Improved blood pressure and resting heart rates
    • Enhanced physical performance
    • Obesity support and weight loss
    • Improved blood glucose, insulin, and leptin levels
    • Enhanced tissue health

    As amazing as these benefits sound, it's crucial to remember that everyone's body responds differently to intermittent fasting. Always check in with your healthcare provider before starting a new eating plan.

    Dos and don'ts of intermittent fasting


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      Do consult a healthcare professional before starting.

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      Do listen to your body and adjust your fasting plan accordingly.

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      Do maintain a balanced diet during your eating periods.

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      Do stay hydrated during fasting periods.


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      Don't force yourself to stick to a plan that doesn't suit your lifestyle.

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      Don't overeat during non-fasting periods.

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      Don't ignore any unusual symptoms like headaches, nausea, or anxiety.

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      Don't engage in intermittent fasting if you're under 18, pregnant or breastfeeding, have a history of eating disorders, or have type 1 diabetes.

    How can I make intermittent fasting work for me?

    Intermittent fasting isn't a one-size-fits-all solution. It’s about finding a plan that fits your lifestyle, supports your health goals, and, most importantly, feels sustainable.

    It's about being the tailor of your own well-being. Let's chat about how you can make intermittent fasting work for you.

    1. Make small adjustments

    Firstly, it's crucial to understand that Rome wasn't built in a day, and neither will your fasting routine. Start by making small changes, like extending the time between your dinner and breakfast.

    Remember, small steps can lead to big changes. It's a lot like watching an episode of "Breaking Bad." You start with one, and before you know it, you've binged the whole series.

    2. Be flexible

    Flexibility is key in intermittent fasting. If you're not feeling great during a fasting period or if a social event falls into your fasting window, it's okay to adjust.

    You're not breaking any "rules." After all, the main goal of intermittent fasting is to make your life healthier, not harder.

    3. Listen to your body

    Finally, it's essential to listen to your body and adjust accordingly. If you're feeling dizzy, fatigued, or unwell during a fast, take it as a signal that you might need to rethink your approach.

    Your body is your best guide, and it can tell you a lot about what works and what doesn't if you listen to it. Remember, intermittent fasting can be a great tool for health and wellness, but it's not for everyone. Always consult a healthcare provider before making significant changes to your diet.

    VitaRx Tip

    Remember, the success of intermittent fasting isn't measured by how long you can go without eating but by how well you can maintain a balance between your fasting and eating periods.

    Advantages and disadvantages of intermittent fasting

    Intermittent fasting is a popular health trend, but as with any dietary regimen, it comes with its own set of pros and cons. It's important to weigh these before deciding if this eating pattern is right for you.

    Frequently asked questions (FAQ)

    Here are some commonly asked questions that we haven't touched upon yet. These should provide you with more insight and deepen your understanding of intermittent fasting.

    Final thoughts

    As we bring this feast of knowledge to an end, let's take a moment to digest all we've learned about intermittent fasting. And remember, there's no one-size-fits-all when it comes to fasting—it's really all about what works best for your lifestyle and body. Just like a diet, if you cheat on it, it's probably not your mate (I'm looking at you, chocolate cake!)

    Sources and references


    Stephanie Wright avatar

    Stephanie brings over 13 years of diverse nursing experience to the table, having honed her expertise in critical care, mental health, and utilization management. Her journey as a registered nurse across these various healthcare sectors underscores her adaptability and deep commitment to patient care.

    Fact checker

    Dr. Dimitar Marinov avatar

    Dr. Marinov has years of experience in scientific research and preventive and clinical medicine. His publications in peer-reviewed journals are on nutritional status, physical activity, and musculoskeletal disorders among adolescents.

    At VitaRx, we're not just passionate about our work — we take immense pride in it. Our dedicated team of writers diligently follows strict editorial standards, ensuring that every piece of content we publish is accurate, current, and highly valuable. We don't just strive for quality; we aim for excellence.

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