Intermittent Fasting for Beginners

Wondering what intermittent fasting is all about? Check out our guide, covering what it is, the different types of intermittent fasting, benefits, risks and if it's right for you.

Did you know being in a fasted state can result in significant health benefits such as improved blood sugar levels and insulin sensitivity?

Intermittent fasting is increasingly becoming the go-to for people who want to lose weight but also reap the other range of health benefits. The interesting thing about intermittent fasting is that it’s not a typical diet (which often puts your body in a state of deprivation). Intermittent fasting, rather, is a lifestyle change.

In this beginner’s guide to intermittent fasting, we’ll explain everything you need to know about the different types of fasting methods, how fasting works, and the potential benefits and downsides of this way of eating.

What is Intermittent Fasting?

Intermittent fasting, or eating only during certain hours, is not a new idea. It has been around for ages, often for health or religious reasons like during Lent or Ramadan.

Nowadays, it’s become a popular way to lose weight and improve health. It’s not just about shedding kilos; it also offers other health perks like:

  • More energy
  • Better cholesterol levels
  • Can help with Type 2 diabetes

One of the main reasons people like intermittent fasting is its simplicity. You’re already doing a form of it when you sleep, as you stop eating from dinner to breakfast. The term “breakfast” actually means breaking your overnight fast.

With intermittent fasting, you don’t have to change what you eat, just when you eat. It’s all about setting specific times when you eat and when you fast.

The Different Types of Intermittent Fasting

There are different types of intermittent fasting, each with its own set of rules regarding when you can eat and for how long you should fast.

These methods vary in their time frames, fasting windows, and levels of calorie restriction but all share the basic concept of alternating between periods of normal eating and times when you eat very little or nothing at all.

Here, we look at some common intermittent fasting methods:

16:8 Intermittent Fasting

This involves eating within an 8-hour window and fasting for 16 hours, typically done daily. For example, you might eat between 10 am and 6 pm. This method is popular because of its simplicity and alignment with normal sleep cycles, allowing for two to three meals within the eating window.

20:4 Intermittent Fasting (Warrior Diet)

Similar to the 16:8 but with a shorter eating window of 4 hours and a longer fasting time of 20 hours. People often choose to eat in the late afternoon or early evening, fitting in one large meal or a few small ones within this time.

5:2 Intermittent Fasting

In this method, you eat normally for five days of the week and restrict calories significantly for the other two days, typically to 500-600 calories. Originally popularized by Michael Mosley, this approach has evolved to allow up to 800 calories on fasting days alongside a Mediterranean diet on regular eating days for better results and nutrition.

Alternate-Day Modified Fast

There are variations in this approach, including fasting every other day or using a modified version where you restrict calories on fasting days rather than avoiding food altogether. This could mean fasting for 36 hours with a 12-hour eating window or having 24 hours of eating followed by 24 hours of fasting.

It’s important to understand there are risks involved in fasting beyond 24 hours, particularly for those who have high training demands or chronic health issues. We recommend you speak to your general practitioner, dietitian or nutritionist before embarking on any fast for a significant amount of time.

Extended Fasts & Absolute Fasts

  • Extended Fasts: These are fasts that last over 48 hours. They are less common and can be challenging and risky, especially without medical supervision. It’s crucial to consult healthcare professionals before starting an extended fast.
  • Absolute Fasts: These involve avoiding all food and drink, including water, usually for religious reasons rather than weight loss or health. It’s critical to get medical advice before undertaking an absolute fast.

How Does Intermittent Fasting Work?

Intermittent fasting involves not eating for specific periods, which helps your body rest and use stored energy, often leading to a shift from relying on sugar for energy to burning fat more efficiently.

Here’s how it works:

Normally, when you eat, your body breaks down the food into energy, using what it needs immediately and storing the rest in your liver, muscles, or as body fat.

The hormone insulin helps in this process, converting carbohydrates into glucose and storing them as glycogen or, when in excess, as fat. Constant eating keeps insulin levels high, which can lead to insulin resistance and increase the risk of Type 2 Diabetes.

Fasting impacts insulin positively, making it more effective at signaling your body to use stored energy since no food energy is coming in. It also reduces leptin, the hunger hormone, leading to an increased metabolism.

As you fast, your body first uses energy from glycogen stores and then starts burning fat. This process not only helps with weight loss but also improves blood sugar levels and hormone balance.

What to Eat During Intermittent Fasting

When you’re doing intermittent fasting, it’s not just about when you eat, but what you eat that counts too. During your eating windows, go for balanced meals packed with nutrients. Focus on whole foods like:

  • fruits
  • veggies
  • lean proteins (think chicken or fish)
  • whole grains (like brown rice or whole wheat bread)
  • healthy fats (such as avocados and nuts).

This combo helps keep you full and energised. Also, drink plenty of water to stay hydrated. Try to avoid junk food and sugary snacks; they might taste good but won’t help your energy levels or overall health. Remember, the goal is to fuel your body with good stuff that keeps it running smoothly!

The Health Benefits of Intermittent Fasting

The most clear-cut benefit from this practice is weight loss.

The actual impact of intermittent fasting on weight can differ widely among individuals, influenced by the specific fasting method used.

Beyond weight loss, there’s increasing research that suggests several other health advantages of intermittent fasting, including:

  • Increased fat-burning ability
  • Lowered insulin and leptin levels
  • Improved blood sugar control
  • Increased growth hormone
  • Management or reversal of type 2 diabetes
  • Improved LDL and HDL cholesterol levels
  • Increased energy
  • Increase focus and cognition
  • Increased longevity
  • Enhanced digestive function
  • Reduced inflammatory markers

The Downsides to Intermittent Fasting

Intermittent fasting may have plenty of health benefits, but there are some possible side effects that can be experienced by fasting for long periods of time. Some of the most common, yet short-term, pitfalls of intermittent fasting include:

  • Hunger
  • Constipation or diarrhea
  • Headaches
  • Light-headed / Dizziness
  • Fatigue
  • Heartburn
  • Muscle cramps

Severe side effects from intermittent fasting, particularly shorter or alternating fasts, are rare. These may include dehydration, refeeding syndrome or excessive weakness. If these symptoms do occur, it’s important to break the fast resume your normal food intake and consult your doctor if they persist.

Who SHOULD NOT Intermittent Fast

Intermittent fasting can be helpful for many, however, some people shouldn’t adopt this approach or any other diet for that matter.

Avoid intermittent fasting if you are:

  • Underweight – below <18.5 BMI
  • Have an eating disorder such as bulimia or anorexia
  • Pregnant
  • Breastfeeding
  • Under 18 years old

Intermittent fasting should be done under the guidance of your health practitioner if you:

  • Have Type 1 or Type 2 Diabetes
  • Are anemic
  • Are on a prescription medication
  • Have high uric acid levels or gout
  • Have a serious chronic medical condition including liver disease, kidney disease or heart disease

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