- 1 How does fasting make you lose weight?
- 2 What happens to your body while fasting?
- 3 Is intermittent fasting good for weight loss?
- 4 Which Intermittent fasting schedule is best to lose weight?
- 5 Fasting weight loss results
- 6 Intermittent fasting for loose skin
- 7 Health benefits of intermittent fasting
- 8 The bottom line
- 9 Lose weight with fasting
Last Updated on December 11, 2023
Intermittent fasting is a globally popular nutrition system. Its fame has now spread beyond the boundaries of Hollywood, for its numerous health benefits as well as the bonus benefits of weight loss and weight control.
There are two different periods in intermittent fasting: the eating period, during which you eat your meals, and the fasting period when you only consume zero-calorie beverages.
How does fasting make you lose weight?
Fasting promotes weight loss through a complex interplay of metabolic and hormonal changes. Here’s a more detailed explanation:
1. Reduced calorie intake
This is the primary driver of weight loss. By restricting your eating window, you naturally consume fewer calories, creating a calorie deficit. A study published in the journal JAMA Internal Medicine found that participants on a time-restricted feeding regimen (16/8) consumed 350 fewer calories per day and lost an average of 3% of their body weight in 12 weeks.
2. Increased fat burning
When you deplete your body’s readily available glucose stores during fasting, it starts utilizing stored fat for energy. This process, known as lipolysis, releases fatty acids into the bloodstream, where they can be used by muscles and other tissues for energy production. A study in the Journal of Nutrition showed that intermittent fasting increased fat oxidation by 23% compared to continuous calorie restriction.
When your body primarily relies on fat for fuel, it produces ketone bodies as a byproduct. These ketones can have several metabolic benefits, including suppressing appetite, further promoting fat burning, and preserving muscle mass. Research published in the journal Cell Metabolism suggests that ketosis can enhance metabolic flexibility and improve insulin sensitivity.
4. Improved insulin sensitivity
Insulin is a hormone responsible for regulating blood sugar levels. Fasting can improve insulin sensitivity, allowing your body to better utilize glucose and potentially reducing fat storage. A study in the journal Diabetes Care found that intermittent fasting improved insulin sensitivity by 31% in individuals with type 2 diabetes.
5. Cellular repair
During fasting, your body may prioritize cellular repair and regeneration processes due to reduced energy intake. This can lead to improved cellular function and potentially contribute to weight loss by enhancing metabolic efficiency. Research published in the journal Aging Cell suggests that fasting can increase the activity of autophagic pathways, which are responsible for cleaning up damaged cells and promoting cellular renewal.
6. Reduced inflammation
Chronic inflammation is linked to various health issues, including obesity and metabolic syndrome. Fasting has been shown to have anti-inflammatory effects, which may contribute to weight loss and overall health improvements. A study in the journal Obesity found that intermittent fasting reduced inflammatory markers like C-reactive protein in individuals with metabolic syndrome.
7. Appetite control
Some studies suggest that fasting can influence the production of appetite-regulating hormones. Ghrelin, the “hunger hormone,” may decrease, while leptin, the “satiety hormone,” may increase, leading to decreased overall calorie intake. Research in the journal American Journal of Clinical Nutrition found that intermittent fasting reduced ghrelin levels and increased leptin levels in overweight and obese individuals.
8. Increased metabolic rate
Short-term fasting may lead to a temporary increase in metabolic rate, also known as thermogenesis. This means your body burns more calories at rest, further contributing to weight loss. A study published in the journal Obesity found that intermittent fasting increased resting metabolic rate by 3.5% in overweight and obese adults.
What happens to your body while fasting?
After you have your last meal of the day and start your fast:
1. Digestion begins:
After you have your last meal, your body starts to digest the food you ate. This is the anabolic (growth) stage of your body.
Carbohydrates, protein, and fats are broken down into glucose, amino acids, and fatty acids to be used for energy and muscle building, or stored for later use.
2. After 4 hours of fasting:
Your body enters the catabolic (breakdown) phase, which means your body starts to use the stored nutrients for energy.
Glucose is your body’s first choice. When the body runs out of glucose, it starts to consume glycogen (the stored form of glucose) to keep your energy at normal levels.
3. After 12 hours of fasting:
Your body enters the long-awaited fat-burning phase because by now you have run out of your glycogen stores.
The fat-burning stage continues until you have been fasting for 18 hours.
In other words, staying hungry for at least 12 hours or more is key for losing weight, as you lose your excess body fat during this stage of fasting.
4. After 18 hours of fasting:
Your body has already started using fat as its main energy source, but as fasting continues, the body starts to transform fatty acids into small particles, called ketones or ketone bodies, in the liver to produce an alternative energy source, because fatty acids are too big to cross the blood-brain barrier. This way they can reach every cell in your body.
Is intermittent fasting good for weight loss?
Yes, intermittent fasting (IF) is good and effective. for weight loss. In fact, several studies have shown that it can be as effective as traditional calorie restriction for weight loss and belly fat reduction. Additionally, it may help improve other health markers, such as blood sugar control and cholesterol levels.
Which Intermittent fasting schedule is best to lose weight?
There’s no single “best” intermittent fasting schedule for weight loss. The ideal approach depends on several factors, including your:
1. Current eating habits: If you’re used to eating three squares a day, transitioning to a more restrictive schedule like OMAD (one meal a day) might be too challenging. Beginners often find success with the 16/8 method, which allows for an eight-hour eating window.
2. Lifestyle and schedule: Consider your daily routine and social commitments. Can you easily skip breakfast or dinner? Will fasting interfere with your work or social life?
3. Overall health: Certain health conditions might necessitate medical supervision during fasting. Consult your doctor if you have any pre-existing health concerns.
Here’s a brief overview of popular intermittent fasting schedules:
1. 16/8 fasting plan: The 16/8 fasting schedule is the most common approach, involving 16 hours of fasting and an 8-hour eating window. A typical schedule could be fasting from 8 pm to 12 pm and eating between 12 pm and 8 pm.
2. The 5:2 method: This method involves eating normally for five days and restricting calories (around 500-600) for two non-consecutive days.
3. Eat-Stop-Eat: Eat-stop-eat fasting plan involves 24-hour fasts once or twice a week, punctuated by regular eating periods.
4. OMAD: OMAD, aka one-meal-a-day fasting plan, involves consuming all your daily calories in one single meal.
Fasting is a sustainable method that can easily become a lifestyle and can help you manage your weight for good. All you need is a suitable intermittent fasting plan for you.
Fasting Kompanion can help you find the most suitable plan for you, or can customize a new plan just for you. You can also pick a plan from our article: Intermittent Fasting Schedules for Weight Loss.
Whether your weight loss goal is a few pounds or around 20 pounds, intermittent fasting will make this journey easier for you.
Fasting weight loss results
Most traditional diets lead to the yo-yo effect, which simply means regaining weight after a diet and being in a never-ending dieting cycle.
With intermittent fasting, you can have your favorite hamburger or pasta and still lose weight – and there’s no yo-yo effect.
Although every individual’s physiology is unique, most people start to lose weight and see a difference in their bodies in the first few weeks.
Intermittent fasting results vary greatly among different individuals’ physiologies and based on the fasting schedules they follow.
The best part of losing weight with intermittent fasting is that you mostly preserve muscle mass if you combine fasting with light cardio exercises such as brisk walking. You can also try Fitness Kompanion’s bodyweight cardio exercises to boost weight loss.
Intermittent fasting for loose skin
While research is ongoing, there are some promising indications that intermittent fasting (IF) may be beneficial for reducing loose skin after weight loss. This potential benefit is thought to be due to a process called autophagy.
Autophagy: During fasting periods, the body goes into a “cellular cleanup” mode. Autophagy is the process by which damaged cells and proteins are recycled and broken down for energy. This process may also help to stimulate the production of new collagen and elastin, which are essential for skin elasticity.
Preliminary studies: Several preliminary studies have shown that IF can improve skin health and reduce the appearance of wrinkles. For example, a recent study published in the journal “Clinical and Experimental Dermatology” found that IF significantly improved skin elasticity and reduced the appearance of wrinkles in women aged 55-65.
More research is needed: However, it’s important to note that more research is needed to confirm the effectiveness of IF for reducing loose skin. Additionally, it’s important to consult with your doctor before starting any new dietary regimen, especially if you have any underlying medical conditions.
Other factors to consider:
- Rate of weight loss: Rapid weight loss is a major risk factor for developing loose skin. Aim to lose weight gradually, at a rate of 1-2 pounds per week.
- Nutrition: Eating a healthy diet that is rich in protein and collagen-boosting nutrients, such as vitamin C and zinc, can help to improve skin elasticity.
- Hydration: Staying hydrated is essential for overall skin health. Aim to drink eight glasses of water per day.
- Exercise: Regular exercise, especially strength training, can help to tone and tighten the skin.
Health benefits of intermittent fasting
The benefits of fasting aren’t limited to weight loss. Thanks to the break your digestive system is taking, your body starts to detox.
Your cells activate autophagy, where damaged and unnecessary components within the cells are broken down and consumed for energy.
Autophagy starts by the 14th hour of the fast. Fully-fledged autophagy starts after a 24-hour fasting period and peaks after 48 hours of fasting.
You can get more autophagy benefits with longer fasting periods. But you should bear in mind that this is a very advanced version of intermittent fasting.
Fasting is a sustainable weight loss and health-boosting approach that can be adapted to almost every lifestyle. Simply re-organize when you eat your meals to see the difference in your body.
Bear in mind that it isn’t ideal to eat too much junk food even if you’re following an intermittent fasting plan.
Try to add healthy proteins, healthy fats, fruits, vegetables, and whole carbs to your diet for a healthier fasting experience.