Dr. Yasmin Imdad gives you the pros and cons of this current global lifestyle trend.
The practice of fasting is intrinsic to our culture, an ancient tradition that has been in practice for centuries. Human bodies have evolved to survive and thrive without food for several hours, days and even longer as people had to hunt and gather their food, like animals. Even 50 years ago, it was easy to maintain a healthy weight as there were no computers and internet, and lifestyles hadn’t changed so drastically. People would stop eating before sunset. They would observe a fast, called vrat, which basically is a resolution to go without food as an act of expiation. Or they would abstain from one meal in the day, or some days in the week, or a few weeks in a year. But today, we are prone to sitting and snacking all day and most of the night, resulting in higher risk of obesity, type 2 diabetes, heart disease and other illnesses.
With many people wanting to find ways and means to reclaim their health, trends like intermittent fasting are gaining momentum. Touted for being an effective means to lose weight and improve health, intermittent fasting is quickly moving into the fad territory. And when something becomes a fad, several problems typically ensue. Hence, when it comes to incorporating any diet regime, it is important to seek guidance and assistance from a healthcare professional.
Intermittent fasting implies an eating schedule where one switches between fasting and eating during a set number of hours. It was popularized in 2012, when research done on fat rats showed that intermittent fasting helps lose weight and improves blood pressure, cholesterol and blood sugar. It has shown positive results on humans as well. A body of researchers claim that the timing of the fast is key to make intermittent fasting a more realistic, sustainable and effective medium for weight loss and also for diabetes prevention.
Because it helps weight loss, intermittent fasting is gaining popularity in current times. The food we eat breaks down with the help of enzymes present in our gut, which eventually ends up as molecules in our bloodstream. The carbohydrates, particularly sugars and grains, break down into sugar which is used up by our cells for energy. If the cells do not use all the energy, it gets stored up in the fat cells as fat. Between meals, if we do not snack, the insulin levels drop and the fat cells then release the stored sugar to be used as energy. The whole idea of intermittent fasting, thus, is to allow the insulin levels to go down far enough and for long enough so that our body burns off the fat.
Intermittent fasting schedules
16:8 – Do not consume anything for 16 hours, and then all the meals and calories for the day are consumed during the 8-hour period. It is the most popular and flexible model as one can choose the 8-hour window as per one’s convenience. While some people choose to skip breakfast and eat from noon to 8pm, others avoid eating late and stick to a 9am to 5pm schedule. This helps in reducing the amount of food consumed which then means weight loss, lower blood pressure, and prevention of hypertension.
5:2 – Is a straightforward intermittent fasting plan where normal food without restricting calories can be consumed for five days per week and for the remaining two days, the calorie intake is reduced to one-quarter of the daily requirement. For instance, if the daily calorie requirement is 2,000 calories, it must be reduced to 500 calories on those two days. There is flexibility as the two fasting days can be selected as per choice and also there are no rules regarding what, when and how much to eat on the full calorie days. However, restricting to one-quarter of calories on two days of the week might make a person ill or faint.
Alternate day: This is an easy-to-remember structure where a fasting day always follows a non-fasting day. Although this schedule has proven weight loss benefits, a full fast every alternate day can be extreme, and overeating on the non-fasting days is tempting.
- Intermittent fasting promotes improved body composition, lowers disease risk and improves brain function. It helps with obesity, insulin resistance, dyslipidemia, hypertension and inflammation.
- Helps lose weight and improve metabolic health.
- If incorporated as a lifestyle change, can help improve range of health issues from arthritic pain to asthma.
- Works well when accompanied with a nutritious, whole foods diet. There is no need for special foods or to diverge from what you normally eat.
- Helps clear out toxins and damaged cells, thus lowering risk of cancer.
- It can be hard to stick with long-term, as it may affect one’s social life.
- Can lead to some health issues like headaches and impaired thinking.
- Requires discipline, restraint and planning ahead.
- Hunger pangs could lead to frustration and overeating.
- Mood swings followed by constipation, fatigue, sleep disturbances, irritability, nausea and anxiety.
- Not recommended for pregnant or breastfeeding women, growing children and adolescents, elderly and individuals vulnerable to eating disorders.
The science behind intermittent fasting is still in its preliminary stage due to the absence of studies on its long-term effects. But in order to gain most from intermittent fasting, be sure to eat a variety of nutrient-dense foods, limit processed and packaged foods, and incorporate a regular exercise routine. Also, before embarking on this plan, make sure you consult a trained healthcare professional.
Dr. Yasmin Imdad is a Senior Consultant – Obstetrics & Gynaecology, Kinder Women’s Hospital and Fertility Centre, Bengaluru, India.