Parul Kharod
By Parul Kharod
In my daily work of nutrition counseling and talking to people about their diets, one of the questions most frequently asked is about fasting. “Can I do fasting?” or “What do you think about intermittent fasting?”
So, let’s tackle that subject here and clear out some basic misconceptions.
Fasting has been done for religious purposes in many communities across the world. It is not a new concept. It is important to understand the purpose and intent of fasting. When done for religious purposes such as in Jain communities or during Ramadan, there are specific methods and rituals that are followed. When to eat, when to fast, how to break the fast, are all done systematically. Plus, the fasting is done for a fixed amount of time.
And that’s the key to everything – consistency and being systematic – having a routine!
What is intermittent fasting?
Basically, it is a way to shorten the timeframe of eating. Intermittent fasting is a strategy that combines periods of eating with periods of fasting into a regular schedule. There are different types of fasting schedules. However, whatever timeframe is selected, you must follow that schedule consistently. So randomly skipping meals is not considered fasting. Our body needs a steady routine for everything, including sleep and meals. We must have a daily routine. So, whether you are doing intermittent fasting or not, we need to eat at regular intervals daily.
Why is fasting thought to be beneficial?
During fasting, the body switches from using the fuel we get from outside through the foods we eat, to burning internal fuel from fat, glycogen and other stored energy. Fasting allows us to use this glycogen and tap into our energetically dense fat reserves to keep us alive until we eat again. This switch from external to internal fuel reserves has many other benefits beyond simply survival. Different types of fasting can activate these benefits to varying degrees.
The most common benefits of fasting include weight loss and fat reduction, and the ability to maintain healthy levels of metabolic markers such as blood glucose, inflammatory markers, blood pressure, and cholesterol. There is also improvement in the gut microbiome.
Several studies have shown that fasting during chemotherapy can significantly reduce adverse side effects, especially nausea/vomiting and fatigue. These fasts during cancer treatment should only be done under medical supervision.
Important considerations:
It is important to remember that intermittent fasting only determines when you will eat. It does not guide you about what to eat. Therefore, if you are not mindful about including a healthy nutrient rich diet for the meals you are eating, you will not see any benefits from fasting. You should not try fasting if you do not already have a set routine. If you tend to skip meals, first establish a daily routine before trying any time-restricted eating.
Who should not fast?
• People with history of seizures or fainting
• Anyone who has a fever, cough, diarrhea, or infections
• Anyone who is underweight, pregnant, or breastfeeding
• Anyone under 18 years of age or over the age of 70, unless they have approval and are under the supervision of a healthcare provider
• Anyone with significant dietary restrictions or history of eating disorder
Types of fasting:
There are different types of fasts. Finding the right one for you depends on your specific goals, lifestyle, level of health, body chemistry and any special physical needs. When it comes to fasting or any other diet regimen, there is no “one-size-fits-all” approach. Do not blindly follow other people and learn to listen to your own body. Do what fits your lifestyle and daily routine, and what you can do on the most consistent basis.
12:12: If you want to get into a routine, this is the easiest to follow, and should be followed by everyone. Keep a gap of 12 hours between your dinner and the next day’s breakfast. For example, finish dinner before 8 pm, and eat breakfast the next day after 8 am. Again, make sure that when you eat from 8 am to 8 pm, consume small balanced meals with a gap of 3-4 hours.
16:8: This is the most common form of fasting practice being done these days. This involves stretching the fasting window to 16 hours and eating within an 8-hour timeframe. Your 8-hour window for eating may be 10 am to 6 pm or 11 am to 7 pm. But again, remember that within these eight hours, eat three small meals spaced apart evenly.
Other types of fasts
The 5:2 Diet: This type of intermittent fast that focuses on fasting during specific days of the week. You eliminate or severely restrict your calorie intake for two (non-consecutive) days of the week and then resume a normal diet for the other five days.
Alternate Day Fast: The basic premise here is to fast on one day and eat what you want the next day, repeating the cycle throughout the week. Some modified ADF approaches allow you to consume up to restricted calories on fasting days.
Other severe fasting regimens include eating only one meal a day or doing a water fast (drinking only water for 48 hours).
Summary
As with any diet, one size does not fit all. Intermittent fasting has shown to have benefits, but it may not be suitable for all. It is also not supposed to be done for prolonged periods of time. Be mindful of what you eat and try to have a consistent routine whether you do intermittent fasting or not.
Parul Kharod is a registered dietitian and licensed nutritionist and works as a Clinical Dietitian. She can be reached at [email protected]
