Intermittent Fasting – Eat in 8 Hours Window & Fast for Remaining 16 Hours

Intermittent Fasting is just a new modern term. It exists in ayurveda for thousands of years. In fact, ayurveda has mentioned two timings for eating food – morning and evening (Ref. Ashtang Sangrah). There were no western terms like – breakfast, lunch, and dinner. In ancient India, people were eating a meal two times a day – one after sunrise and one before sunset. There was 8 to 10 hours gap between main meals. This was perfect timing. In some villages, this is still in practice in India. According to ayurveda, Pitta timings starts after sunrise and our body has higher digestive capacity after sunrise. Our digestive capacity diminishes after sunset and during sleep. Ayurveda recommends eating a light meal in the evening. So, in the evening, you should eat food that you can easily digest. (Ref. Ashtanga Sangrah). Let’s read what Dt. Sneha is saying about Intermittent Fasting. – Dr. Jagdev Singh

16/8 Intermittent Fasting

Fasting, which is voluntary abstinence from food intake for a specified period of time has been practiced across many different religions and cultures for thousands of years.

Today, new varieties of fasting have been practiced with the major goal being weight loss and fat loss. One of the fasting techniques that has skyrocketed in popularity is 16/8 intermittent fasting. This type of fasting is time-restricted, easy to follow and requires minimal effort.

As compared to many other diet plans, 16/8 intermittent fasting is easy to implement, flexible and less restrictive.

In this type of fasting, foods and calorie-containing beverages can be consumed for 8 hours per day and food or beverage intake should be avoided for the remaining 16 hours.

You can select your 8 hour window period, it can either be 9 am-5 pm where you can eat your breakfast, lunch and an early dinner around 4 pm or you can choose 1 pm-8 pm, where you skip your breakfast and opt for lunch and dinner. (1)

Just like each coin has two sides, 16/8 intermittent fasting also has some pros and cons.

How to Do Intermittent Fasting

Let us first learn in detail about how to do intermittent fasting:

Pick Your Fasting Window

As mentioned above, you need to shorten your eating window to 8 hours per day. You can choose your time slot, but keeping it earlier, for example- 7 am- 3 pm is most beneficial. If waking up early is not possible, you can even opt for 10 am- 6 pm, where you can eat an early dinner and post 6 pm all you can drink is plain water, black tea or black coffee.

Choose Healthy Meals

During intermittent fasting, you do not need to count calories. But, this does not give you the freedom to consume as many calories as you want. Be a smart eater and choose foods that are a good source of calories, vitamins, minerals, antioxidants and dietary fiber. Just because you are allowed to eat everything, do not opt for sugar-laden and high-fat foods to fill your tummy.

Eat Satisfying Meals

Choose foods that are calorie dense and fiber-rich. Eating foods rich in dietary fiber keeps the stomach full and it will delay hunger pangs during the fasting period. Whole grains, pulses, fruits and vegetables are good sources of dietary fiber.

Say Yes To Lean Protein and Healthy Fat

It is necessary to consume adequate protein throughout the 8 hour window period. Protein helps in muscle building and fat loss, which may further enhance weight loss and improve overall health. Some good sources of protein are:

• Dals, pulses and lentils.
• Sprouts.
• Nuts and seeds.

Consume Oil and Fat in Moderation

Eating deep-fried or high-fat foods during the 8-hour period can negate the beneficial effects associated with 16/8 intermittent fasting. Choose healthy cooking oil options like olive oil, coconut oil, peanut oil and canola oil.

16-Hours Fasting Period

Many individuals tend to overeat during their 8 hours window period, in order to prevent hunger pangs during the fasting period. This can have negative effects and may lead to ineffective results. During the fasting period, it is advised to drink plenty of plain water to keep you full and to reduce the overproduction of acid in the stomach. This may prevent hyperacidity and hunger pangs. (2, 3)

Health Benefits of 16/8 Intermittent Fasting

Intermittent fasting has several health benefits, as follows:

Aids Weight Loss

16/8 intermittent fasting is beneficial for people who want to lose weight. Studies have observed that time restricted feeding reduces overall caloric intake without calorie counting and decreases fat mass without affecting the lean mass.

Fasting for 16 hours boosts the metabolism, which helps in weight loss. This is possible because fasting increases the expression of adiponectin, a hormone that acts in the brain to increase energy expenditure and cause weight loss. Brief periods of fasting also increase the resting energy expenditure, which further enhances weight loss. (4, 5)

Reduces Inflammation

16/8 intermittent fasting improves health by fighting inflammation. Inflammation plays a key role in the onset and progression of diseases and disorders. It suppresses the markers of inflammation and enhances the activity of anti-inflammatory substances. Hence, intermittent fasting is a great strategy to reduce the risk of chronic diseases. (6)

Reduces Insulin Resistance

Studies have observed that intermittent fasting has the ability to modulate blood glucose and insulin levels. Fasting causes a rise in the adiponectin levels, which is positively correlated with insulin sensitivity. Certain inflammatory compounds trigger insulin resistance.

Adiponectin possesses anti-inflammatory effect, which helps in the reduction of inflammatory markers, thus leading to an improvement in insulin sensitivity. Because intermittent fasting improves the level of adiponectin, it automatically improves blood glucose and insulin chemistry too. (7, 8)

Boosts Cognitive Power

16/8 intermittent fasting improves cognitive functions and brain structures, a research reports. Studies have found that restriction of food for certain hours of the day (for example- in 16/8 intermittent fasting, intake of food is restricted for 16 hours) attenuates the brain aging process.

This type of fasting also induces ‘autophagy’, a self-cleansing natural mechanism of the body, where the old cells are broken down and recycled. This helps in memory formation and reverses age-related memory decline.

Fasting without caloric restriction increases the tolerance of the different areas of the brain to toxins and stress, that in turn protects the brain cells and the nerve cells. Oxidative stress is a contributing factor to brain aging and impairment of learning and memory. Intermittent fasting is associated with a drop in the level of oxidative stress. This improves brain function and reduces cognitive decline. (9, 10)

Enhances Longevity

Intermittent fasting is linked to an improvement in overall health. First, it helps in weight loss, which reduces the risk of metabolic diseases. Second, it reduces inflammation and oxidative stress, which play a crucial role in the initiation and progression of chronic diseases. Third, intermittent fasting improves blood glucose level and boosts brain function. All these factors may contribute to a healthy living and a longer lifespan. (11)

Disadvantages Of 16/8 Intermittent Fasting

16/8 intermittent fasting is beneficial for health, but if it is not done in the correct way it can lead to disadvantages.

• Because the eating window is only for 8 hours, some individuals may tend to overeat in order to make up for the fasting hours. Such an action may not enhance weight loss. This may even lead to bloating, hyperacidity and other digestive problems.
• Following an unhealthy diet for a prolonged period of time may lead to unhealthy eating habits.
• At the beginning of 16/8 intermittent fasting, some of you may experience weakness, fatigue, headache and dizziness. In the initial stage, these symptoms are common, but they will subside with time, as you get used to it.
• It is always better to ask your doctor and a registered dietician before you start with any kind of intermittent fasting.
• One should keep in mind that. The results of 16/8 intermittent fasting depend on your food choices. Hence, try to incorporate healthy foods and make sure you drink plenty of water throughout the day. (12)

Bottom-Line

• 16/8 intermittent fasting is a safe and healthy practice. If you have any underlying medical condition, ask your doctor before starting intermittent fasting.
• Intermittent fasting is not suitable for children, pregnant women and lactating mothers. Women who are trying to conceive must also avoid it.
• Do remember to eat healthy foods during your eating period.
• If you experience any negative symptoms for a prolonged period of time, consult your health physician immediately.