Many people fast, but they do it for different reasons. Muslims fast during Ramadan, which means that they are not allowed to eat, drink, smoke or have sexual intercourse from dawn until sunset for 29-30 days. The 5:2 diet also involves fasting, however only for two days a week along with five days of eating normally with no calorie restrictions, and it is often used by people who wish to lose weight. But what does fasting mean to the body’s well-being?
Many studies have been made regarding the effect of fasting
Doctor Michael Mosley is a great proponent of the fasting diet and mentions that this diet does not only have a positive effect when it comes to losing weight – it also offers several other health benefits. As an example, he brings out studies of intermittent fasting which show that people not only see improvement in their blood pressure and cholesterol levels, but also in their insulin sensitivity. Another study tested how a weekly day of only drinking water would affect the body, and here researchers found a reduced risk of developing diabetes for people in the high-risk group. Other studies which have tested two- or four-day fasting, i.e. long-term fasting, showed that this might ‘reboot’ the immune system by getting rid of old immune cells and regenerating new ones. This process is thought to be able to protect against cell damage caused by factors like ageing and chemotherapy.
The effect is caused by…
The effects mentioned above are due to a number of things.
The lack of energy from food during fasting will make the body start pulling glucose out of storage in the liver and muscles after around eight hours of fasting. Once this stored glucose has been used, the body will start using fat as the source of energy which results in weight loss. Burning fat can contribute to a preservation of muscle mass and a reduction of cholesterol levels. In addition, fasting causes a detoxification of the body, as toxins stored in the body’s fatty tissue are dissolved and removed from the body.
In regard to the effect on the immune system, researchers from University of Southern California mention that when you starve, the system tries to save energy. One thing the body can do to save energy is to reuse a lot of the unnecessary immune cells, especially those that might be damaged, and use them as an energy source. In addition to observing a renewal of the immune system’s cells in mice after fasting for two to four days, researchers also found that cancer patients who fasted for three days prior to chemotherapy were protected against immune cell damage, a condition otherwise caused by chemotherapy.
Not just pros
Fasting is, however, not only associated with benefits. According to NHS, intermittent fasting is also linked with several health risks.
Many people will experience dehydration, mainly because their bodies do not get any type of fluid from food. It is therefore recommended that that you make sure to stay properly hydrated during fasting.
If you are used to eating breakfast, lunch, dinner and snacks in between, periods of fasting can be a major challenge. Therefore, fasting might increase stress levels and disrupt your sleep. Dehydration, hunger or lack of sleep during fasting can also lead to headaches. In addition, fasting can cause heartburn – a lack of food leads to a reduction of stomach acid, which helps digest food and destroy bacteria. The smell of food or even the thought of it during the fasting period could trigger the brain into telling the stomach to produce more acid which leads to heartburn.
Besides, the question whether the diet is an effective way to lose weight arises. While many people who wish to lose weight try the 5:2 diet because many dieticians recommend it, others are not proponents of fasting diets. This is because they do not believe that the resulting weight loss is long lasting, but rather that the fast weight loss is due to a loss of fluids caused by caloric deficiency. As soon as you start eating normally, the fluids will return, and the weight loss will thus slowly vanish. In addition, many health experts fear that fasting diets will steer people away from healthy recommendations regarding fruits and vegetables and lead to eating disorders or binge eating.
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