Intermittent fasting means that you don’t eat for a period of time each day or week. Intermittent fasting has many benefits. Research shows that intermittent fasting is a way to manage your weight and prevent — or even reverse — some forms of the disease. Intermittent fasting (IF), one of the most talked-about diets right now, is a way of eating that designates periods of time for eating and for fasting.
The premise behind intermittent fasting is relatively simple. When our insulin levels go down far enough and for long enough, as they do during a fasting period, we’re able to burn off fat. Insulin levels drop when a person is not consuming food. During a period of fasting, decreasing insulin levels cause cells to release stored glucose as energy. Repeating this process regularly, as with intermittent fasting, leads to weight loss. In addition, this type of fasting often results in the consumption of fewer calories overall, which contributes to weight loss.
IF makes intuitive sense. The food we eat is broken down by enzymes in our gut and eventually ends up as molecules in our bloodstream. Carbohydrates, particularly sugars and refined grains (think white flour and rice), are quickly broken down into sugar, which our cells use for energy. If our cells don’t use it all, we store it in our fat cells as, well, fat. But sugar can only enter our cells with insulin, a hormone made in the pancreas. Insulin brings the sugar into the fat cells and keeps it there.
Between meals, as long as we don’t snack, our insulin levels will go down and our fat cells can then release their stored sugar, to be used as energy. We lose weight if we let our insulin levels go down. The entire idea of IF is to allow the insulin levels to go down far enough and for long enough that we burn off our fat.
Intermittent Fasting Benefits Fasting
Weight and body fat loss
Weight loss is the most common reason for people to try intermittent fasting (Source). By making you eat fewer meals, intermittent fasting can lead to an automatic reduction in calorie intake. In addition to lowering insulin and increasing growth hormone levels, it increases the release of the fat-burning hormone norepinephrine (noradrenaline).
By helping you eat fewer and burn more calories, intermittent fasting causes weight loss by changing both sides of the calorie equation.
Increased fat burning
As stated earlier, normally you’ll receive energy from the carbohydrates that you consume. This will prevent you from burning the fat you have stored in your body. Yet when you are fasting, you are forcing your body to use the fat you have stored for energy. This by itself will lead to instant and rapid fat loss, which means that you will not only look better, but actually be healthier too.
Lowered blood insulin and sugar levels
Insulin is a hormone in the body that regulates the function of cells. Insulin is made by the pancreas and is secreted when we eat food. It then binds to signal cells and allows our body to store the sugars as energy. The less insulin we need to store these sugars, the more sensitive we become to insulin, and the better insulin can do its work in the long term. When we eat 5 to 6 times a day, our insulin levels stay too high for a long period of time. This insulin won’t be used effectively, and this will eventually raise our resistance to it. When we are resistant to insulin, we can develop type 2 diabetes or prediabetes.
Improving type 2 diabetes
Diabetes is a disease that prevents us from storing all the sugars we consume, because the insulin that our pancreas produces won’t work properly. When this happens the sugars will not be stored as energy and will remain in our blood stream, leading to high blood sugar levels and hardening of the blood vessels. This can eventually cause kidney diseases, heart attacks, erectile dysfunction, loss of vision, strokes, nerve damage and much more critical health problems.
Animal studies have shown that IF improves insulin sensitivity and prevents obesity in mice. In humans, one recent case report published in BMJ found that IF successfully treated insulin resistance and lowered hemoglobin A1C (a measure of blood sugar control over several months) in participants with insulin-dependent type 2 diabetes. Another promising outcome: after following IF for several months, all of the participants in the study were able to discontinue their insulin medication entirely.
Improved mental clarity and concentration
Fasting has been shown to have anti-aging effects in the human brain. It can help improve neuroplasticity (the brain’s ability to form new neural connections) and fight inflammation, which correlates to better memory, not to mention improved capacity to learn and retain new information.
As your body gets used to intermittent fasting, your energy levels increase. Your body becomes more efficient at using energy and this helps improve mood, mental ability, and long-term performance. Apart from weight loss, the less-known benefit of intermittent fasting is said to be an increase in energy. Eating several times throughout the day means our metabolism goes through cycles of breaking down carbohydrates and turning them into blood sugar. Eventually, it is used for energy or stored in cells for later.
There have been a few animal and rodent studies that have shown IF may extend life span, possibly because fasting seems to build resistance to age-related diseases. A review published in Current Obesity Reports in June 2019 noted that while these findings are promising, it’s been hard to replicate them in human studies. Until that happens, it’s best to be skeptical about this potential benefit.
Animal studies have shown that both IF and general calorie restriction can reduce inflammation levels, though clinical trials are few and far between. The authors of a study publishedin Nutrition Research wanted to know if that link existed among humans, too. The study involved 50 participants who were fasting for Ramadan, the Muslim holiday, which involves fasting from sunrise to sunset, and eating overnight. The study showed that during the fasting period, pro-inflammatory markers were lower than usual, as was blood pressure, body weight, and body fat.
Keep in mind that intermittent fasting may have different effects on different people. Talk to your doctor if you start experiencing unusual anxiety, headaches, nausea, or other symptoms after you start intermittent fasting. The most common side effect of intermittent fasting is hunger. People with certain medical conditions should not fast without consulting with a doctor first.