9 Intermittent Fasting Dos And Don’ts

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Intermittent Fasting Dos and Don'ts

Intermittent fasting dos and don’ts – why do you need to know them?

Allowing your body to digest meals for extended periods can help you lose weight and provide numerous potential benefits rather than simply cutting calories. Intermittent fasting’s core idea is not to radically alter the foods you consume but rather when you should eat them.

Fasting has been a significant tradition in many religions and societies around the world for thousands of years. New types of fasting now give this traditional practice a modern twist. If you’ve been wanting to give intermittent fasting a try, it’s important to understand its limitations in detail and be aware of the dos and don’ts when it comes to fasting.

Intermittent Fasting: What Is It?

Most of you have probably heard about intermittent fasting (IF) in some form or another. It’s one of the biggest diet trends right now but for some, it could just be another fad diet. But why do people swear by it?

The fact is, the purpose of intermittent fasting is not to restrict calories and food all day long. Rather, this weight loss strategy is about skipping a few meals to encourage your body to burn extra or stored fat for energy.

The body essentially enters ketosis during fasting (burning fat instead of carbohydrates for energy). The process of burning fat to produce energy is what causes weight loss. In a nutshell, intermittent fasting generally entails programmatically switching between the eating and fasting phases.

Unlike other usual diets with numerous restrictions, you have control when you do intermittent fasting; which is a wonderful thing especially for beginners. By choosing your eating window, when you eat and what you eat (caloric intake), you get to establish the rules and when you apply them. That’s actually how easy intermittent fasting is.

Would You Benefit From An Intermittent Fasting Diet?

There is evidence1 that, when done correctly, intermittent fasting provides numerous health benefits. It can help people lose weight (promotes fat loss), achieve low blood sugar and cholesterol, prevent or control diabetes, and improve the health of your brain.

The human body burns fat for energy and sheds extra pounds if the fasting period is long enough. Further details of these and many other health benefits resulting from losing the additional fat are discussed below.

Health Benefits of Intermittent Fasting

1. Changes the way that cells, DNA, and hormones work.

Human Growth Hormone (hGH) levels rise and insulin levels fall when you fast. When your body is fasting, your cells start vital cellular repair procedures and changes in gene expression2.

Human Growth Hormone (hGH) Levels

Human Growth Hormone (hGH) helps to maintain normal body structure and metabolism, including keeping your blood sugar levels within a healthy range. The hGH levels in the blood could increase when you fast. Increased levels of this hormone promote muscular growth and fat loss, among many other advantages3.

Lower Insulin Levels

When your insulin is high, you’re more likely to store calories as fat, instead of burning them for energy.

When you fast, the insulin levels in the blood drastically decrease, which promotes fat burning4.

Cellular Repair

The body initiates crucial cellular repair activities, such as removing cells containing waste5.

2. Can aid in visceral fat reduction and weight loss.

You eat fewer calories while also modestly increasing your metabolism by engaging in intermittent fasting. Resulting in its highly powerful strategy for shedding pounds and visceral fat.

Increased concentrations of norepinephrine (noradrenaline), lower insulin levels, and higher hGH levels all promote the breakdown of body fat and make it easier to utilize it as fuel. Because of this, short-term fasting actually helps you burn more calories by raising your metabolic rate.

An analysis of the scientific literature from 2014 found that intermittent fasting can result in weight loss of 3-8% over the course of 3–24 weeks6.

More research is required to determine how fasting affects muscle loss. Taking everything into account, intermittent fasting has the potential to be a very effective weight loss strategy in losing visceral fat.

3. Can lower insulin resistance, which lowers your risk of developing type 2 diabetes.

In recent decades, type 2 diabetes has increased in occurrence as a diagnosis. It’s interesting that intermittent fasting has been demonstrated to significantly improve insulin resistance and cause a striking drop in blood sugar levels.

Anything that lowers insulin resistance ought to lower blood sugar levels and prevent type 2 diabetes, according to research7. Making it an ideal health and weight loss diet.

4. Can lower the body’s oxidative stress and inflammation.

One of the factors that contribute to aging and many chronic diseases is oxidative stress. Uncontrolled oxidative stress may accelerate the aging process and could contribute to the development of a number of conditions from inflammation.

When inflammation is too high, it can eventually start damaging healthy cells, tissues, and organs. According to studies, the body’s oxidative stress8 and inflammation9 can be decreased by intermittent fasting. This could protect against aging and the emergence of many diseases such as cardiovascular disease and arthritis.

5. May lengthen your life expectancy.

The capacity of intermittent fasting to increase longevity may be one of its most intriguing benefits.

According to a study10 on rats, those that were fasted lived longer than those who weren’t. A similar study also showed that intermittent fasting extends life expectancy in mice in a manner comparable to chronic calorie restriction11.

Although this is yet to be determined in humans, these results on animals could suggest that intermittent fasting may lengthen life.

6. May have positive effects on the brain.

What and how we consume food affects our body and is essential to our brain. Your brain actually uses 20% of your body’s energy. This is why healthy diets are an important part of staying healthy.

Different metabolic processes that are known to be crucial for brain health are improved by intermittent fasting. There is also a promising study12 that fasting can prevent and treat many neurological disorders in animals. Although, due to a lack of research, much less evidence is available on humans.

However, there is a study indicating that fasting might aid in Alzheimer’s disease prevention. In a series of case studies, 90% of those who underwent a lifestyle intervention that included daily short-term fasts saw a significant improvement in their Alzheimer’s symptoms13.

7. Possibly preventing cancer.

Unchecked cell proliferation is a hallmark of cancer. It has been demonstrated14 that fasting has a number of positive metabolic benefits that may lower the risk of cancer. It could potentially play an important complementary role in medicine by promoting disease prevention, enhancing disease treatment, delaying the aging process, and stimulating stem cell-based regeneration.

8. Cellular healing mechanisms are triggered.

During intermittent fasting, starvation may activate autophagy where the cells in your body will enter the “waste removal” process.

Autophagy is essential for your cell to survive and function. It is your body’s normal process that deals with the destruction of cells in the body, reusing old and damaged cell parts. The breakdown products are then recycled for important cell functions and help destroy bacteria and viruses that cause infection and may prevent normal cells from becoming cancer cells15.

9. May promote cardiovascular health.

Several heart health indicators or “risk factors” are linked to either an elevated or lowered risk of developing heart disease.

Numerous heart disease risk variables, including blood pressure, cholesterol levels, triglycerides, and inflammatory markers, have been shown in studies to be improved by intermittent fasting. Furthermore, intermittent fasting has been associated with improved outcome after a cardiac event16.

However, more research is needed for the potential to improve cardiovascular outcomes and the approach may not be suitable for everyone. Additionally, intermittent fasting can be harmful if done incorrectly or excessively.

Different Fasting Periods

As you may already be aware, there are numerous types of intermittent fasting. Depending on your approach and how strictly you adhere to the rules, all of them might help you lose weight at varying rates. Popular methods for intermittent fasting and their eating periods include:

  • Overnight Fast. The easiest fast to follow since it slightly mimics how you normally eat. Limit to a 12-hour fast and a 12-hour eating period where your eating window is throughout the day such as 6 AM to 6 PM.
  • 16/8. One of the popular time-restricted fast. You only have an eight-hour window to feast and a 16-hour fast each day. For instance, eating only between 8 AM-4 PM.
  • 5:2 Diet. Where you continue eating normally for five days, but on the final two days of the week, you limit your calorie consumption to 500–600.
  • Alternate-day Fasting. This type of fasting is similar to 5:2 except you switch daily between a full feasting day and a 500-calorie restricted day.
  • Eat, Stop, Eat. This involves a 24-hour fast once or twice per week and eating for the remaining five days. You choose any day of the week or 2 nonconsecutive days per week where you abstain from eating for a full 24-hour period.
  • Whole Day Fast. You basically only eat one meal each day. The most common eating window for a whole day fast is dinner time.

The Dos and Don’ts Of Intermittent Fasting


1. Identify your fasting method.

Understanding how to intermittent fast is crucial if you want to keep your diet balanced and avoid taking unnecessary risks.

If you wish to undergo intermittent fasting, you must first determine how you will fit this eating pattern into your life, particularly concerning if you have activities such as attending social gatherings or having an active lifestyle.

Remember, there is no one approach to losing weight that works for everyone.

2. Consult your physician.

Make an appointment to see a health care professional to receive their advice before beginning any diet program or intermittent fasting.

3. Drink a lot of water.

You deplete a lot of glycogen when you’re doing intermittent fasting, which causes you to lose a lot of fluid as well. Glycogen is your body’s stored form of glucose (sugar) that is the main source of energy. So make sure to drink water and lots of it when fasting. It is advised to consume 8 to 12 glasses or 2-3 liters of water daily.

Aside from water, you can also drink these liquids while on fasting periods:

To maximize the weight loss effect of intermittent fasting, do avoid the following liquids while in the fasting phase:

While you keep yourself hydrated by drinking more water, it can also compensate for the water loss caused by the lack of meals consumed. It will also keep your hunger at bay, all the more helping you in your intermittent fasting journey.

4. Consume fiber- and fat-rich meals.

Filling up on nutrient-rich foods maintains a healthy weight and balances your diet. Balance your meals by including a variety of whole foods, such as:

Fruits: Include tomatoes, apples, bananas, berries, oranges, peaches, and pears.

Vegetables: Broccoli, brussels sprouts, cauliflower, cucumbers, leafy greens, etc.

Whole grains: Barley, buckwheat, quinoa, rice, oats, and others.

Healthy Fats: Include avocados and olive oil.

Lean Protein: Eggs, fish, beans, meat, poultry, nuts, and seeds.

5. Listen to your body.

Our bodies will all react differently to intermittent fasting, so there is no way of really telling how you will respond until you have started fasting. Pay attention to the changes in your body, energy levels, or other possible negative symptoms that may arise when you start fasting. If you start feeling weak, dizzy or otherwise feel like you can’t go about your regular daily routines, immediately stop the fast. 

When you initially begin fasting, you could feel weary or sluggish because your body uses less energy than it is accustomed to. If this feeling persists, you may want to break your fast and make adjustments a long the way. Better yet consult your health care professional again for assistance.


1. If you have a health or medical condition, don’t fast.

Your body needs all the energy it can get if you are pregnant, have a chronic condition, or are taking medicine. Since fasting deprives the body of energy, starting a fasting routine is not advised. Although intermittent fasting is fundamentally a means to lose weight and keep it off, other weight loss techniques can be better suited to your individual requirements. To learn more about the weight loss strategies that might work best for you, speak with your doctor.

Who should NOT TRY intermittent fasting?

It is not advisable to do intermittent fasting if you suffer from any of the following conditions:

  • Type 1 Diabetes
  • Eating disorders
  • Underweight (BMI 18)
  • Taking insulin for Type II Diabetes
  • Any hypoglycemia circumstances.

2. Engaging in energy-intensive activities when fasting.

You must balance fasting, nutrition, and exercise if you want to lose any weight or at least keep the weight off that you have already lost. However, it is not advised to exercise or perform other vigorous activities when fasting.

Doing light to moderate activity is preferable to vigorous exercise. Overdoing it can harm your body and can take a toll on your mental health, making it more challenging to stick to your fasting schedule. At the same time, avoid using your fast as an excuse to do nothing but idle around.

What exercises can you do while on intermittent fasting?

Suppose you exercise while in a fasting stage; it’s possible that your body will start utilizing your muscle cells as fuel. This is because carbs are the primary fuel source for high-intensity activities. Therefore, performing such activities while fasting or towards the conclusion of your fast is not ideal and may reduce the positive effects of your workout. If you’re new to intermittent fasting, you’re more likely to feel less motivated to work out hard. Here are some suggested low-intensity exercises you can do to prevent that:

  • Walking/Jogging: Walking is the most basic exercise that is recommended for everyone to perform during a fast. You may add in a light jog if you’re up to it. Simply moving around, you can accomplish as much as you can because walking or jogging is not only simple but it can also be stress-free. It keeps your mind occupied when all you can think about is food and fasting starts to seem like a lot of work. Walking while fasting is not any more demanding than walking on days when you are eating.
  • Yoga: As both yoga and fasting are cleansing rituals, they enhance each other’s positive effects. You may also experience deeper levels of meditation which helps keep your mind busy as you fast. It is advised to practice yoga later in the day, an hour before breaking the fast.
  • Cycling: Cycling is a low-impact form of exercise that while fasting, will still increase your fat loss process. It can be an easy enough exercise that provides options for those who want to work out without stressing their body.

3. Eating plenty of unnatural and processed foods.

Natural lipids, fiber, and protein are taken out of food during processing. Additionally, it contains additives like sugar, which could encourage you to consume more and more, leading to a diet that is not healthy. If you’re doing intermittent fasting, as tempting as they are, you will want to avoid the sugary, empty calories that come from processed foods and drinks.

In order to maintain a balanced diet when practicing intermittent fasting, it is advised to prepare meals that are rich in nutrients. At the same time, the best way to avoid the impulse to eat unhealthy food is to replace these with healthier alternatives and make this your daily habit.

4. Overeating or bingeing on food.

An unhealthy practice of intermittent fasting could lead to binge eating. Bingeing is the biggest side effect you must overcome when breaking your fast. You will consume more calories as a result of bingeing, which will reduce the advantages of fasting altogether. Even when you finish your fast, always keep a healthy, balanced meal and practice self-discipline.

Recap Of The Intermittent Fasting Dos And Don’ts

Intermittent fasting is an incredible diet option for both beginners and fitness enthusiasts. But beyond simply not eating, there are other aspects that you should take into consideration.

In following weight loss diets, there is always a risk of poor nutrition or poor diet practices; and like all diets, intermittent fasting will not be for everyone. Always keep in mind the intermittent fasting dos and don’ts for you to be guided properly and to maximize the positive effects of fasting.

Remember to have the right fasting method that suits your condition. Observe balanced meals to receive proper nutrition and stay hydrated especially when you’re active. Most importantly, follow the advice of a health professional and never forget to listen to your body.


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