Does Doing Intermittent Fasting in Longer Term Sustainable if My Metabolism Crashes?

Can someone help me understand?? I’ve always been told that if you skip meals, then your body goes into starvation mode, and your metabolism crashes to compensate so that the next time you eat, you retain those calories extra hard. I am doing IF now (day 2 of only having an eating window of 6 hours), and I feel fine so far and have lost a pound, but it worries me that this might not be sustainable long term if my metabolism crashes. Can someone explain how this doesn’t happen while on the keto diet?

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Intermittent Fasting 4 Answers 870 views 0

Answers ( 4 )


    Keto diet allows for meals that provide a low insulin spike as well as deplete carbohydrate storage, for the most part, to adapt to utilizing fat as the primary energy source; dietary and body fat. (Too much & frequent insulin secretions store energy as body fat.)

    Resistance to hormone insulin can occur with refined carbohydrates over the years, and your body secretes more insulin to compensate for the resistance. I.E. Obesity/type 2 diabetes or becoming overweight/pre-diabetes.

    Fasting will break up the insulin resistance most effectively because you allow your body to access the fat stores, and bring back balance and sensitivity on the hormonal level by experiencing the lower spectrum of insulin levels.

    High insulin levels inhibit hormone-sensitive lipase, which burns body fat. Insulin does go up when you eat. So you can’t exactly be in bodyfat-burning mode after the standard American meal.

    Fasting also will help keep the weight off because it is directly normalizing insulin levels and increasing insulin sensitivity.

    Just like if you are a lightweight when it comes to alcohol, that will represent insulin sensitivity. (Which is good in this case if you want not to be overly-anabolic.) Insulin resistance is built up from frequent meals and ingesting sugars/processed carbs and can be thought of as building a tolerance to alcohol, so it takes more for you to be drunk. That comparison is odd because, in this case, we want to lose weight, but I feel it could still explain it well.

    The metabolic rate actually increases when body fat stores are adequate, and you fast, due to a noradrenaline increase. Because insulin is low, it has more direct access to body fat, and it is a steady, stable stream of energy access for many people.

    If you were to eat small standard American meals/snacks throughout the day and cut your calories, your metabolism would drop because the frequent/possible high carb foods keep insulin high. Your body cannot access the fat stores when that is the case, and your hypothalamus compensates for this by lowering metabolic rate.


    Starvation mode is a myth perpetuated by the food industry to get people to eat, eat, eat. Our bodies respond so well to periods of a fasted state because the food was scarce in times of old, especially during winter, and our bodies are designed to accommodate that.


    When my friends are interested in Intermittent Fasting l, always encourage that they start with a minimum of a month of keto first to make it easier to do Intermittent Fasting. It is a total lifestyle change, but for me, it makes it easier to lose weight and stick with keto in general. I read and studied Intermittent Fasting and long term fasting for about three months before I tried my first window. Now I do a 24hr alternate day fast weekly and hope to do a three day fast this month.


    One important side note, make sure that you're eating enough when NOT fasting. Not really a problem when you do lunch and dinner. But especially when you just do one meal a day as I do.


      That's hard because I'm always so busy. In the past normal day, I might not get dinner until 11 pm. Now I've told myself I'm only eating between 2 pm-8 pm, so the first day, I got distracted and missed the window and just went without dinner. It didn't kill me, and I admit that I ate a couple of dill pickle spears before bed, but they are 0 cal/carb/etc., so I figured it was a safe risk for my first day, and the next morning I was down a pound. Day 2 I skipped dinner again because I just didn't want it and because I was still full from my large lunch and it didn't bother me at all. I haven't weighed yet this morning.


        I just do the OMAD and eat Keto with no calorie restriction. It's great!

        It's ok to eat late. sometimes I don't eat until 9 pm. Or just plan on your midday meal as being the big one.

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