I am sure this may have been asked before but not sure I saw a consensus answer. Not sure I will but any help is appreciated. A little background.
I (35 M) have been dieting off an on since I was 12 in the conventional “biggest loser” form of dieting. I cut calories a lot and started exercising a lot. I would lose 20 pounds and then gain it back. I have done this for over 20 years now and have become overweight.
As of March 15th, I have been quarantined at home with the current situation and started to research Dr. Fung and intermittent fasting. 6 weeks in, I am happy with the progress doing 16/8 and restricting calories to about 1500 calories which is 500 short of my TDEE. Reading his articles and watching videos I see why the conventional eat less exercise more may only yield short terms results with an eventual weight gain due to the body’s metabolism slowing down to compensate.
My question is, if I want to lose significant weight, should I still be practicing eating less calories in my eating window doing IF? Or should I be eating maintenance and only rely on exercise to create a deficit to try to keep my metabolism from slowing down. Can you lose weight doing IF without a calorie deficit?
My goal is sustained weight loss, but would not like to destroy my metabolism in the process if that is indeed what calorie restricting does.
You probably won’t need to do it - particularly at the start of your weight loss, if you are very overweight.
As you progress and reach your goal weight, you may want to improve your diet generally, which for most people ends up as less calories than they used to eat, as vegetables etc are less calorie dense than junk.
However if 1500 calories 16:8 is working for you, why not stick to it? What you may find if you start plateauing is that you can simply change tactics for a couple of weeks - eg throw a couple of 24 or 36 hour fasts in there.
Dr Fung really encourages eating until you’re satisfied. In the beginning you will overeat but your appetite will regulate. It’s really really hard to dismantle this idea of cico, but he’s saying it’s not going to work in the long run and not what you need to focus on. Fast and eat plenty of nourishing whole food, moderate protein, lots of healthy fat and veggies and listen to your body. You are trying to shift to a new relationship with food where you can stop focusing on calories so much. Lots of people do cico and it works, but it’s not sustainable. The weight will eventually come back because you can’t keep lowering your calories forever.