If eating less helps you lose weight, then eating nothing at all must really shed the pounds, right? Fasting is often used for detoxification, political protest, and spiritual renewal — but what about fasting as a means to accelerate weight loss?
What Is Fasting?
Fasting is when you voluntarily go without food. Before agriculture created a reliable food supply, hunter/gatherers often had no option but to fast when there was no nourishment available. The body stores excess calories as saturated fat during times of feast, and taps into those energy stores to continue functioning during times of famine.
Why Fast?
Digestion takes a considerable amount of energy. The over-consumption of food creates a backlog of digested food waiting to be processed and eliminated. The body can only deal with so many toxins at once, so it stashes them in fatty tissue, to be filtered later on. The Standard American Diet (SAD) consists largely of processed food laden with artificial colorings, flavorings, and other chemicals such as pesticides. The digestive tract is under constant stress from exposure to environmental threats– viruses, bacteria, toxins and parasites. Fasting can give your body a break from the hard work of digestion so that your liver and immune system can heal, repair, and catch up. In fact, we all practice a mini-fast every night, which we break in the morning with our first meal. We call it breakfast because we break our fast.
What Happens During a Fast?
Your body has reserves of glycogen, the sugars that form the body’s basic energy supply. Those reserves are tapped during the first day. Once they’re depleted, the body uses fat for energy in a process called ketosis. It occurs on the second day of the fast for women, and on the third day for men. During ketosis, the liver converts stored fat and damaged tissue into ketones, which are then used for energy by the brain, heart, and muscles. At this point in the fast, hunger pangs vanish and are replaced by increased energy levels and mental alertness.
Will I Starve?
Starvation begins when the stored energy sources are depleted, and vital tissues such as organs are utilized to maintain life. The length of time a person can go without eating varies, depending on the individual.
What About Muscle Loss?
During a fast, some muscle loss will occur at first. That’s because the brain needs glucose – the sugars it gets from glycogen. At first, the body breaks down muscle tissue for a ready supply of glycogen. However, the brain would need a pound of muscle converted to sugar each day in order to function. So if the fast continues, the body shifts to ketosis, which allows muscle mass to be mostly preserved or decomposed at a very slow rate.
How Much Fat Can I Lose?
The weight loss at the beginning of a fast is an illusion, because it’s mostly water weight. Once the body enters ketosis, fat is utilized at the rate of about half a pound per day.
How Long Should I Fast?
Most fasts last for three days or less. Any longer should only be attempted under a doctor’s supervision. Alternative medical practitioners sometimes treat chronic conditions with a fast that lasts two to four weeks.
Is Fasting for Weight Loss Healthy?
There is disagreement as to whether fasting should be engaged in at all, and there are convincing arguments on both sides of the issue.
One supporter of the beneficial effects of fasting is Joel Fuhrman, MD, author of Fasting and Eating for Health. He and other proponents list these advantages:
- The American diet is low in nutrients, which renders the body unable to rid itself of toxins.
- Processed foods result in a build-up of AGE – advanced glycation end waste products in the cells – and lead to premature aging, diabetes, atherosclerosis, and the deterioration of organs. Fasting allows the body to remove AGE waste products.
- Fasting in short bursts can help dieters learn to say no to food.
- Fasting for four days per month can help treat chronic conditions that do not respond to other treatments.
- Scientific studies have shown that combining periodic fasting with eating a calorie-restricted diet increases lifespan.
Those who are against fasting list these reasons:
- Every time you go without eating, your body slows its metabolism by about 20%. Therefore, when you start eating again, the food you eat is even more fattening than before.
- It focuses you on weight loss, rather than health. The ultimate goal should be a healthy body with a lower percentage of body fat, which is achieved over the long term by adopting a healthy lifestyle.
- Your body needs protein and calcium. Without dietary protein, your body begins to eat itself, consuming muscle to meet its protein needs. Without dietary calcium, your body dissolves calcium from your bones, accelerating osteoporosis.
- Dehydration – The dramatic weight loss at the beginning of a fast is mostly due to loss of fluids.
- To lose weight, it’s important to build muscle mass, which boosts your resting metabolism. Loss of muscle mass during the first days of fasting is counter-productive to weight loss goals.
So with all these experts saying that fasting can actually cause you to gain weight, is there any reason to make fasting a part of your weight loss strategy? Yes, because the benefit may not be in the number of pounds shed, but in getting control of your appetite. And although your metabolism may slow, your insides will be cleaner and will therefore use food more efficiently, meaning you will need fewer calories to fuel your usual level of activity.
How to Fast Safely for Weight Loss
First of all, it’s important to have someone monitoring you. If you live alone, tell a friend what you’re doing and keep in touch. Never fast longer than three days without medical supervision, and never enter into a fast if you are taking medication or have serious health issues. Drink plenty of water while fasting to counter dehydration. You may feel bad during the first days of a fast, since toxins released from fatty tissue will be released into the bloodstream, so try to get as much rest as possible.
To begin fasting, lighten your diet gradually over the course of several days. First eliminate heavy foods like dairy and meat. Then, cut down on grains, beans, and nuts. The day before a fast, only eat light foods, such as soup, salad, and fruit. Reverse the process as you leave the fast, gradually incorporating heavier foods into your diet.
In my next post, I’ll talk about what research studies show to be the safest, easiest, and most effective way to lose weight by fasting – the Intermittent Fast.
A biology researcher with a keen interest in the science of eating right for a heal, Matthew Papaconstantinou, PhD, writes articles about diets and weight loss programs that are featured in fitness related sites. His blog offers a Medifast coupon and a discount for Nutrisystem , two scientifically researched meal replacement diets.
Other Posts You'll Find Useful:
If eating less helps you lose weight, then eating nothing at all must really shed the pounds, right? Fasting is often used for detoxification, political protest, and spiritual renewal — but what about fasting as a means to accelerate weight loss?
What Is Fasting?
Fasting is when you voluntarily go without food. Before agriculture created a reliable food supply, hunter/gatherers often had no option but to fast when there was no nourishment available. The body stores excess calories as saturated fat during times of feast, and taps into those energy stores to continue functioning during times of famine.
Why Fast?
Digestion takes a considerable amount of energy. The over-consumption of food creates a backlog of digested food waiting to be processed and eliminated. The body can only deal with so many toxins at once, so it stashes them in fatty tissue, to be filtered later on. The Standard American Diet (SAD) consists largely of processed food laden with artificial colorings, flavorings, and other chemicals such as pesticides. The digestive tract is under constant stress from exposure to environmental threats– viruses, bacteria, toxins and parasites. Fasting can give your body a break from the hard work of digestion so that your liver and immune system can heal, repair, and catch up. In fact, we all practice a mini-fast every night, which we break in the morning with our first meal. We call it breakfast because we break our fast.
What Happens During a Fast?
Your body has reserves of glycogen, the sugars that form the body’s basic energy supply. Those reserves are tapped during the first day. Once they’re depleted, the body uses fat for energy in a process called ketosis. It occurs on the second day of the fast for women, and on the third day for men. During ketosis, the liver converts stored fat and damaged tissue into ketones, which are then used for energy by the brain, heart, and muscles. At this point in the fast, hunger pangs vanish and are replaced by increased energy levels and mental alertness.
Will I Starve?
Starvation begins when the stored energy sources are depleted, and vital tissues such as organs are utilized to maintain life. The length of time a person can go without eating varies, depending on the individual.
What About Muscle Loss?
During a fast, some muscle loss will occur at first. That’s because the brain needs glucose – the sugars it gets from glycogen. At first, the body breaks down muscle tissue for a ready supply of glycogen. However, the brain would need a pound of muscle converted to sugar each day in order to function. So if the fast continues, the body shifts to ketosis, which allows muscle mass to be mostly preserved or decomposed at a very slow rate.
How Much Fat Can I Lose?
The weight loss at the beginning of a fast is an illusion, because it’s mostly water weight. Once the body enters ketosis, fat is utilized at the rate of about half a pound per day.
How Long Should I Fast?
Most fasts last for three days or less. Any longer should only be attempted under a doctor’s supervision. Alternative medical practitioners sometimes treat chronic conditions with a fast that lasts two to four weeks.
Is Fasting for Weight Loss Healthy?
There is disagreement as to whether fasting should be engaged in at all, and there are convincing arguments on both sides of the issue.
One supporter of the beneficial effects of fasting is Joel Fuhrman, MD, author of Fasting and Eating for Health. He and other proponents list these advantages:
Those who are against fasting list these reasons:
So with all these experts saying that fasting can actually cause you to gain weight, is there any reason to make fasting a part of your weight loss strategy? Yes, because the benefit may not be in the number of pounds shed, but in getting control of your appetite. And although your metabolism may slow, your insides will be cleaner and will therefore use food more efficiently, meaning you will need fewer calories to fuel your usual level of activity.
How to Fast Safely for Weight Loss
First of all, it’s important to have someone monitoring you. If you live alone, tell a friend what you’re doing and keep in touch. Never fast longer than three days without medical supervision, and never enter into a fast if you are taking medication or have serious health issues. Drink plenty of water while fasting to counter dehydration. You may feel bad during the first days of a fast, since toxins released from fatty tissue will be released into the bloodstream, so try to get as much rest as possible.
To begin fasting, lighten your diet gradually over the course of several days. First eliminate heavy foods like dairy and meat. Then, cut down on grains, beans, and nuts. The day before a fast, only eat light foods, such as soup, salad, and fruit. Reverse the process as you leave the fast, gradually incorporating heavier foods into your diet.
In my next post, I’ll talk about what research studies show to be the safest, easiest, and most effective way to lose weight by fasting – the Intermittent Fast.
A biology researcher with a keen interest in the science of eating right for a heal, Matthew Papaconstantinou, PhD, writes articles about diets and weight loss programs that are featured in fitness related sites. His blog offers a Medifast coupon and a discount for Nutrisystem , two scientifically researched meal replacement diets.
Other Posts You'll Find Useful: