The thought of fasting may invoke feelings of dread or moans and complaints, but the principle could deliver some potent health benefits. Intermittent fasting may be the key to helping you prevent and treat diabetes and lose weight.
What is Intermittent Fasting?
Intermittent fasting means choosing when to eat and when to abstain from food. It is deliberate and controlled. Cycling between eating and fasting helps to regulate the hormones that control glucose metabolism and fat storage. Intermittent fasting allows the body to draw energy from fat cells, which leads to weight loss.
Intermittent fasting is still somewhat controversial but can provide significant health benefits when used appropriately. It is not for every person or everybody.
How Does It Work?
To understand how periodic fasting works, you must appreciate the basics of digestion – energy consumption, storage, and some of the key hormones associated with regulating these processes.
Food is broken down into smaller pieces in the digestive system so the nutrients can be absorbed into the bloodstream, then distributed throughout the body. Carbohydrates (like bread, pasta, cauliflower, and carrots) are sugar molecules that are chemically combined into long chains. Proteins (for example, meats and nuts) are made up of amino acids, and fats are composed of individual fatty acids. All are essential to the body. Since carbohydrates are made of sugar molecules, they are broken down into smaller pieces of sugar, called glucose. Glucose provides the energy that all cells need to function correctly.
This glucose (or energy) must either be used or stored. Insulin is the hormone that tells the energy where to go. It is the driver that controls whether glucose is pulled into the cells for immediate use or whether it will be stored in long or short-term storage locations. Glucose is initially stored short-term as glycogen in the liver and muscle cells. This storage location has limited space but is easy to access, and glycogen can quickly be converted back to its usable form of glucose.
When short-term storage is full, there is long-term storage with virtually unlimited space, but it takes a little more work to retrieve. This energy is stored in the fat cells. When there is an abundance of glucose in the bloodstream, and glycogen storage is full, glucose is pushed into fat cells. When fat cells are stuffed to capacity, the body can make more fat cells to store the energy. It’s a fantastic survival technique, but not necessary in our current society.
Compare it to heading to the airport to catch a flight. You can either be dropped off at the doors and head into the terminal immediately or have to go park. If you have to park a vehicle, you can go to short-term or long-term parking. The long-term lot has more space but is a little harder to reach. It takes more time and effort to catch the shuttle and get back to the front doors of the airport terminal to get to your desired location ultimately.
When the body needs more energy, the short-term storage of glycogen will be used first. Glycogen stores can supply approximately 24 to 36 hours of energy. If the demand for glucose continues without new glucose coming in (as in the fasting state), the body will switch over to pulling from long-term energy storage in the fat cells. This is how intermittent fasting helps with weight loss. It forces the body into breaking down fat to use as energy. This is a more complex pathway, so the body only does it when it is required.
What Is Insulin Resistance?
Insulin resistance occurs when there are constantly elevated levels of glucose in the bloodstream. The body responds by secreting more insulin, but the cells don’t listen very well to what insulin (the driver) says. This often occurs when large amounts of carbohydrates are consumed (particularly simple carbohydrates), and there is a lack of physical activity. Muscle cells require a lot of energy, especially with exercise, so if there is less activity, there is a diminished need. Insulin resistance means there is more insulin in the system; hence there is a higher capacity to store incoming glucose. Since glycogen storage is limited, it often goes to long-term locations and is stored…as fat.
How do I do Intermittent Fasting?
SHORTER FASTS are often done most days of the week. This means limiting meals to an 8-hour window during a 24-hour time frame, for example, eating between 11:00 and 7:00 pm. The eating period could also be limited to 4 or 6-hours, depending on what works for you. It takes two to four weeks to adapt to this new way of eating, but most people report increased energy, focus, productivity, and they feel “leaner” after a month.
LONGER FASTS are done less frequently, generally two to three times per week, and involve just once a day eating. For example, eating dinner on one day and skipping all meals and snacks until dinner the next day. An alternate regimen includes regularly eating five days a week and mostly fasting two days per week. On the two fasting days, 500 calories per day may be consumed, either as one meal or spread throughout the day. A low-carb diet on the “normal” days will make fasting days easier to maintain. It is important not to binge during non-fasting times. Fasting more than 36-hour should be supervised by a medical professional.
Normal activities (including exercise) should continue, even on fasting days. If you participate in long/endurance-type workouts, however, you may benefit from eating before exercise. Fluids are still essential to maintain during fasting, but they are typically limited to water, coffee, or tea (without sugar or artificial sweeteners) to get the benefits of decreased insulin. If whole food categories are removed from your nutrition plan, remember to get the necessary vitamins and minerals from another source. The body tends to absorb these nutrients best from natural food sources, but a multivitamin or supplement may be required.
Weight control, appetite, and glucose metabolism are complex processes that involve multiple hormones and body systems. Insulin, however, is a significant player. Intermittent fasting may be the answer to helping you lose weight and improve overall health, especially if you exhibit signs of insulin resistance, pre-diabetes, or a condition called metabolic syndrome. Talk to your provider if you have questions.
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