11 Benefits And 7 Dangers Of Fasting For Weight Loss

Written by Anamika M
Last Updated on

Fasting is an age-old practice that is often carried out for religious reasons. But these days, when people have become more concerned about their weight, fasting is more often practiced to lose weight, than for religious reasons. During fasting, people eat little to no food. It is true that fasting results in weight loss but there are also some negative effects for the same.

Fasting for a day or two is not dangerous, but it can harm the people suffering from chronic diseases. It also harms children and pregnant women. There are also medical fasts that are supervised by physicians. These fasts are perfectly safe for everyone. The regime for fasting also varies, but the basic fast usually allows only fresh juice, any laxative concoction or water. There are also some fasting regimes that include the consumption of few solid foods that provide few or low calories.

What Is Fasting?

Fasting is defined as an act of abstinence from, or reduction in food, drink or both, for a specified period. A fast can be an absolute or intermittent fast. Absolute fast is complete abstinence from all food and liquid for a defined period, such as a single day or some days. Intermittent fasts are only partially restrictive as they limit consumption of particular foods or substances. Apart from being a spiritual activity, fasting offers several health benefits. In fact, it is an effective way of incorporating healthy changes in your lifestyle.

Types Of Fasts

Most of the fasting, especially in India, is of a religious nature. But it can also be practiced for other reasons such as cleansing and detoxifying the body, weight loss, treatment of a medical condition, etc. There are many forms of fasting. Proper care should be taken in case of any medical condition before beginning a fast.

a. Juice Fast

Juice fasting involves consumption of juices of fruits and vegetables during the fasting period. No solid foods are eaten during this period which can last for a day to 2 weeks. This type of fasting requires careful planning. One needs to get enough minerals and vitamins from a variety of fresh fruits and vegetables. This fast is meant for detoxification and weight loss.

b. Water Fast

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As the name suggests, water fast involves consumption of only water for the duration of the fast. Your body goes through several changes when it is deprived of water. This fast should be resorted to only after proper consultation with your physician. Medically supervised water fasts have proven to be beneficial in normalizing blood pressure.

c. Cleansing Fast

Cleansing fast is meant to cleanse the colon of accumulated food and toxins. It usually involves a liquid drink containing lemon juice, some form of simple sugar for calories and Cayenne pepper or any other spice. This liquid is taken 6 to 12 times daily, and the fast can last from 1 to 14 days. A more intense cleansing fast involves consumption of a laxative tea twice daily, once in the morning and evening. However, you should be aware of its negative effects before resorting to this fast.

d. Liquid Protein Fast

Liquid protein fast is meant to cause weight loss in obese patients. It involves liquid protein diet to enable people to lose weight between 10 to 100 lb. This kind of fasting requires proper medical supervision.

e. Diagnostic Fast

Certain medical tests and procedures require you to abstain from eating or drinking anything except water for 8 to 12 hours prior to testing. For instance, a diagnostic fast may require you to take the fasting glucose tolerance test. This is meant to measure blood glucose levels to diagnose diabetes or hypoglycemia.

f. Partial Fast

These fasts basically restrict a particular type of food such as rice, wheat, or meats. It includes solid food but restricts the amount of food to less than 1 to 3 complete meals.

g. Religious Fast

Most religions employ fasting as a means of spiritual purification and showing devotion to God. Different religions prescribe different forms of fasts. For instance, in the Catholic faith, Ash Wednesday, and Good Friday are obligatory fast days. In Hinduism, fasting is done on certain days such as “karva chauth”. Similarly, Islam employs fasting in the month of Ramadan from sunrise to sunset which involves abstinence from food, drink, sex and smoking during the 30-day fast.

How To Do It Right?

Though fasting provides several health benefits, it also associated with adverse effects like dehydration, electrolyte imbalance starvation, etc. Thus, fasting in the right manner is absolutely essential to minimize the negative effects and reap maximum benefits from your fast. The tips given below can greatly help in making your fast more effective.

  • Prepare Yourself Mentally And Physically

Fasting is much more than just abstaining from food and drink. Religious fasting is more of a spiritual and physical cleansing. Before resorting to spiritual fast, you need to be mentally ready to forgo the normal things that define your life. You can begin by thinking about the purpose of the fast and what you want to achieve. This will prepare you for the first day of the fast.

  • Keep It Short

If you are aiming for weight loss, you don’t have to fast for days at a stretch to get metabolic or weight loss benefits. Skipping a meal every other day is enough to cause moderate weight loss. Fasting for as little as 20 hours at a time can improve insulin sensitivity and other metabolic functions. It is not advisable to fast for more than 36 hours.
Keep Yourself Hydrated

Certain fasts such as Ramadan and Yom Kippur require you to go without water throughout the fast. Though this does not cause any lasting harm, you are most likely to feel dehydrated towards the end of the fast. Thus, it is important to keep yourself hydrated after the fast. If you are not fasting for religious reasons, make it a point to drink plenty of water during your fast.

  • Have A Pre-Fast Meal

The pre-fast meal is extremely important as it provides the needed strength and energy throughout the fast to go without nourishment. Ramadan fast is started by eating before sunset. Though it is not advisable to gorge yourself before beginning your fast, you can definitely eat something to keep yourself energized in the course of fast.

  • Avoid Strenuous Exercise While Fasting

During a fast, you have to go without nourishment for hours. So it is important to conserve energy for your daily activities. Taking a brisk walk is fine, but you should avoid indulging in strenuous physical activity and intense workouts. This will enable you to preserve energy to strive yourself for the spiritual connection.

  • Avoid Operating Heavy Machinery

Most of us have to work while fasting. But as far as possible, operating heavy machines such as automobiles should be avoided while fasting as this can drain your energy and make you feel dehydrated. Proper sleep and rest are other pre requisites to successful fasting.

  • Begin With A Partial Fast

If you are a beginner at fasting, you can start off with a partial fast which restricts certain food items. You can drink water and consume fruits in the course of the fast. You can also try having an early dinner and refrain from food for a 16 hour period before having breakfast. This will prepare you for a complete fast which involves going without food and drink. To begin with, you can go on a moderate fast incorporating any of the following food items.

  • Raw food comprising of fruits, vegetables, seeds and nuts
  • A single food diet such as a fruit or rice gruel
  • Mineral rich bone or vegetable broths
  • Green smoothies
  • Fresh pressed vegetable or fruit juices
  • Salads
  • Khichdi
  • Maintain Proper Nutritional Intake
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Ensure to eat wholesome nutritious food when you are not fasting. Since fasting reduces your appetite, the nutritional quality of food becomes even more important. Avoid gorging on junk food after breaking your fast as this will adversely affect your health.

  • Avoid Overeating After The Fast

Do not indulge in overeating after ending your fast. In fact, it is advisable to eat more of solid foods and smaller portions of snacks.

  • Do Not Compromise Your Health

It should be kept in mind that fasting is not meant for everyone. It is not advisable for persons diagnosed with certain medical conditions like hepatitis as well as pregnant or nursing women. Moreover, if your weight starts dipping below the healthy weight range as a result of fasting, it is a clear indication of nutritional deficiencies.

Benefits Of Fasting

1. Promotes Detoxification

Fasting detoxifies your body. Processed foods contain a lot of additives which become toxins in the body. Some of them cause the production of advanced glycation end products (AGEs). Most of the toxins are stored in fats which are burnt during prolonged fasting. This results in the release of toxins. When you do not eat or drink during the day, your body starts eating into fat reserves to create energy. This helps in burning away harmful toxins present in fat deposits. The liver, kidneys and other organs of the body get involved in this detoxification.

2. Facilitates Weight Loss

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Weight loss is one of the greatest benefits of fasting. This is because when you fast, your body is forced to use the stored fats for getting energy. Lipolysis increases and insulin decreases during fasting.Eating less food slows down your metabolism to conserve energy. Fasting also increases the catecholamines. These catecholamines help in providing some energy while burning fat in our body during fasting. Professionally supervised fasts are best for controlling serious obesity as they offer both medical and psychological support during the process of fasting, ultimately leading you towards healthy eating habits.

3. Decreases Appetite

Fasting is a better option than certain fad diets where you end up gaining back all the weight you lost. This is because the reduction in the food consumed throughout fasting causes your stomach to shrink gradually. This requires you to eat lesser food to feel full. Fasting is, hence, a great option to get into the habit of healthy eating. When your fast is over, your appetite is less than before, and you are less likely to indulge in overeating.

4. Rests your Digestive System

Fasting gives rest to your digestive organs though the normal functions such as the production of digestive secretions continue at reduced rates. This helps in maintaining the balance of fluids in the body. Breakdown of food takes place at a steady rate. Energy is also released in a gradual pattern. The production of acids in the stomach, however, continues uninterrupted during fasting. However, patients with peptic ulcer should take medical advice before resorting to fasting.

5. Normalizes Blood Pressure

Normalizes Blood Pressure
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Fasting is an effective non-drug method of reducing blood pressure. Hence, it reduces the risk of atherosclerosis, clogging of arteries by fat particles. Fasting causes the body to use up the glucose and later fat stores for producing energy. During fasting, metabolic rate as well as fear hormones like adrenaline and noradrenaline are reduced. This keeps your metabolism steady and within limits, resulting in the reduction of blood pressure.

6. Lowers Cholesterol

One of the positive effects of fasting is the reduction of cholesterol in the blood. This results in improvement of cardiovascular health and lower risk of heart disease, heart attack or stroke. This lower cholesterol level can be maintained by following a healthy diet after the fast is over.

7. Reduction In Blood Sugar

As stated earlier, fasting causes the breakdown of glucose to provide energy to the body. This reduces the production of insulin and rests the pancreas. Glucagon is produced to cause the breakdown of glucose, thus resulting in the reduction of blood sugar.

8. Resolves Inflammatory Response

Research has shown that fasting can resolve inflammatory diseases and allergies. Inflammatory diseases include rheumatoid arthritis, arthritis and skin diseases like psoriasis. Fasting is believed to promote healing of inflammatory bowel diseases such as ulcerative colitis.

9. Improves Immunity

Following a balanced diet in between fasts can boost immunity, eliminate toxins and reduce fat storage. Breaking your fast with fruits causes an increase in the body’s store of essential vitamins and minerals. Vitamins A and E are good antioxidants which help to boost immunity.

10. Helps To Overcome Addictions

Fasting is of great help in reducing the cravings for nicotine, alcohol, caffeine and processed foods. Fasting can help the addicts to overcome their addictions. It promotes a desire for natural foods such as fruits and water. In this way, it promotes healthy lifestyle.

11. Mental And Emotional Benefits

Fasting improves mental clarity and focus, thus providing you with greater freedom, flexibility and energy for the day to day activities of life.

Dangers Of Fasting For Weight Loss

  1. Fasting, no doubt reduces the calorie intake. Though this is good for weight loss, it can also cause some health problems like muscle loss.
  1. During a fast, your body goes into a conservation mode which means, calories are burned more slowly and steadily.
  1. Usually, the initial weight that is lost is ‘water weight’ or primarily fluid. This means no fat is lost. So at times, this weight loss trick is temporary and any lost weight usually returns on going back to your regular diet.
  1. The weight regained is usually fat because the slower metabolism makes it easier to gain the lost weight.
  1. Some other side effects of fasting include headaches, muscle aches, dizziness, fatigue, low blood sugar, diarrhea and weakness.
  1. Fasting for a long term may lead to anemia, irregular heartbeat, a weakened immune system and liver or kidney problems.
  1. Fasting to lose weight can also result in mineral and vitamin deficiencies, and when your body becomes deficient in
  1. various important vitamin and minerals, it tends to fall sick and may encounter other health problems and diseases.

Prolonged fasting is strictly not advised. Fasting for a period of two days is safe. It is advised that you intake adequate quantities of water, juices, and fruits so that the body doesn’t fall deficient of any mineral or vitamin. If you are planning for fasting in order to lose weight, then it is advised that you consult a physician. This will lower the risk of getting effected by the harmful impacts of fasting for weight loss.

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Anamika M
hey hi, Anamika here. An indenpendent and nature lover. Writing is my hobby and my first love.It is a big stress buster. I love dining out and exploring new places as it gives me a kind of adrenalin rush. I find solace in spirituality
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