Monday, April 25, 2022

Does Intermittent fasting work?


Art by @nikhilrajguruart

 

A recent study about weight loss is causing waves. It showed that there is no difference in the weight lost by people who did intermittent fasting vs those who did calorie restriction. If this report leads to intermittent fasting losing favour with people, we will be losing out rather than gaining anything.

Let us understand the basics of weight loss. How do we lose weight? What is lost when we lose weight? 

Weight doesn’t vanish out of the body magically; it has a physical means. Primarily weight is related to food intake. Let us understand what happens to the absorbed food. The main chunk of absorbed food is carbohydrates, fats and proteins (the rest are traces which do not have a great impact on body weight). These, through various mechanisms, are broken down finally into carbon dioxide and water. That’s it! (That’s oversimplification, but really, that’s it). Carbon dioxide is breathed out whereas water is added to the reserves. So come to think of it, only way to lose body weight is by breathing out more and more carbon dioxide!!! This concept was mind-blowing to me.

Once I understood this, it was easy to see only 2 ways to control weight: reduce intake of carbon rich (high caloric) food and perform activities that increase CO2 production (exercise). Simple, isn’t it? But that’s not easy to do.

This write-up, being my rant about intermittent fasting, will deal with only the former idea of reducing high caloric food intake. When we begin our weight loss journey, we always start out with calculators which ask us to reduce 25% of our required caloric intake. As I am 75kg adult male, with lifestyle involving moderate physical activity, my daily caloric limit is around 2000 kcal. So a 25% reduction brings it down to 1500. What’s on the menu for 1500 kcal? Did you know that 2 idli, 1 vada with chutney and sambar is 700 kcal, and a regular south Indian meal is close to 1000?!

A highly motivated individual (not me) would make a fool proof meal plan of 500 kcal per meal, count the calories, day in and day out and must continue that for years together! This is where (almost) everybody fails. You end up craving for food leading to snacking (the worst kind of food ever - with super high calories – 4 marie biscuits are 100 kcal ). By snacking, you fail to restrict your caloric intake. Consequently you don’t lose weight but you end up losing heart to continue with this weight loss journey. Why can’t we sustain this diet? We need to know a bit of physiology of hunger and satiety to understand that.

There are 3 pathways by which satiety and hunger are controlled. They are (without getting too technical):

1. neurenteric pathway – recognises the stretch of the stomach (leads to satiety)

2. hormonal pathways – based on food passing through the gut, sugar levels etc (too complex for me)

3. psychological – motivation, goal, reward, etc.

All pathways relay to centres in the hypothalamus, which has the final say. So, if we kindle the satiety pathways and try to inhibit the hunger pathways, we can trick ourselves into consuming less calories while not feeling hungry.

In the above scenario, with only 500 kcal per meal, we were not reaching any of the satiety pathways – no stomach stretch and no mental satisfaction with such a small portion either. In addition, when the hormonal pathways (over which we have no control) kick in, it becomes extremely difficult not to stray from the plan, leading to the snack attack or worse, the binge. This provides a bit of psychological satiety but at the cost of a tremendous amount of calories which is wayyy beyond the budget. 

I did try the restrictive diet and as you can expect I failed miserably. I needed something which would lower my caloric intake, satisfy my love for food and needed only a little motivation. A hard task. That is when I adapted intermittent fasting to suit my needs.

I saw intermittent fasting as a means to reduce caloric intake. I started by having only 2 full meals a day instead of 3. I timed my meals such that I wouldn’t feel too hungry for too long. The solution that worked for me was a late breakfast and an early dinner. I did not restrict my caloric intake for individual meals – I had hearty meals which gave a good stretch to my stomach (satiety pathway) and gave a psychological contentment that I had a full meal. And an added benefit was that I was not counting my calories every second. This meal would be enough for many hours, and I wouldn’t be thinking of food until my hormonal pathways started triggering hunger. This used to be around 3pm for me. I got into a habit of drinking a glass of milk at this time. And by the time I felt hungry next, it would already be dinner time. I would have an early dinner at around 7 pm – a tasty full meal. Hunger mechanisms are not so potent when you are sleeping soundly. In the morning, I would have water-based tea, to keep me going till my late breakfast. I restricted my calories by having two 800 kcal meals and gradually shifted towards more low-calorie high-volume foods (like fruits) which in turn makes the meal healthier.

Everything requires effort and practice, and so did this. But the effort needed was minimal. Unlike crash and burn diets, this could be practiced long term. It reduced my snacking significantly. I never felt that I had given up on good food (and for a foodie like me, that was important). My brain is at peace with this routine now. I am doubly happy as I have lost over 10 kg within 1 year while eating everything I love, and my motivation has still not decreased. 

I am still not at the end of my weight loss journey. My weight has stagnated at a few kgs above where I want it to be. But I decided that I won’t be changing my diet anymore but starting with the other mantra I spoke about earlier. Exercise.

Please don’t discount intermittent fasting just because one study found 1000 people who were motivated to reduce their caloric intake for 1 year. For  normal people I still think intermittent fasting works wonders.

-Vishwas

 

P.s Did you like the funny sketch in the beginning? Check out @nikhilrajguruart for more amazing stuff.