When you hear the term ‘fasting’ you may think of fad diets and feeling very ‘hangry’. But recently fasting has gained a lot of merit as research suggests that intermittent fasting may help improve weight loss, reduce inflammation, improve brain health and reduce the risk factors for heart disease and cancer.
“He who eats until he is sick must fast until he is well.”
What is intermittent fasting?
Intermittent fasting is not a diet, but rather a dietary pattern of eating. It involves only eating during a certain window of time each day, and choosing not to eat for the remainder of the day – allowing the digestive tract to rest. There are many different ways to intermittent fast, but the most popular are:
- Regularly eat during a specific time period. For example, only eating from noon-8 PM, essentially skipping breakfast. Some people only eat in a 6-hour window, or even a 4-hour window.
- Skip two meals one day, taking a full 24-hours off from eating. For example, eating on a normal schedule (finishing dinner at 8PM) and then not eating again until 8PM the following day.
- Restricting calories to 25% of energy needs 2 days a week. For example, usual energy needs might be 2200 calories. 5 days a week you consume 2200 calories and 2 days you eat only 25% of that, so 550 calories. This is also known as the 5:2 diet.
What are the benefits of intermittent fasting?
Weight loss. Intermittent fasting will make you eat fewer meals. So unless you’re eating significantly more in those meals, you will be in a calorie deficit, which means weight loss! Fasting also improves metabolic rate by up to 14%, helping you burn more calories. Intermittent fasting can cause more fat loss and less muscle loss compared to continuous calorie restriction.
- Reduce insulin resistance – type 2 diabetes. Studies have shown that intermittent fasting can reduce blood sugar levels by 3-6% and fasting insulin reduced 20-31%. As blood sugar and insulin are main features of type 2 diabetes, fasting may reduce the risk factors.
- Reduce inflammation and oxidative stress. Studies show that intermittent fasting can reduce oxidative damage and inflammation in the body. This should have benefits against aging and development of numerous diseases.
- Reduce markers for heart disease. Studies show that intermittent fasting can improve numerous risk factors for heart disease such as blood pressure, cholesterol levels, triglycerides and inflammatory markers.
- Repairs the cells. When we fast, the cells in our body initiate a ‘waste removal’ process which involves breaking down and metabolising old and dysfunctional proteins which build up over time. This process may provide protection against several diseases including cancer and Alzheimer’s.
- Prevent cancer. Animal studies suggest fasting to have many beneficial effects on metabolism that may lead to reduced risk of cancer. Fasting has also shown to reduce the side effects of chemotherapy.
- Brain Health. Intermittent fasting may have important benefits for brain health. It may increase growth of new neurons and protect the brain from damage.
- Extend lifespan. One of the most exciting applications of intermittent fasting may be its ability to extend lifespan. Animal studies have shown that intermittent fasting extends lifespan in a similar way as continuous calorie restriction. Although this is far from being proven in humans, intermittent fasting has become very popular among the anti-aging crowd.