I know that technically IF also puts you in a calorie deficit but I was wondering if it was dangerous to also only eat 700-1000 calories per day (recommended deficit for women) while fasting? I plan to also lift/exercise everyday (maybe one rest day I need to see how I feel). If anyone has any tips for fasting please comment!!
edit: 700-1000 is way too low, did more research and calculator told me around 2000 calories/day would be a good deficit!!
I’m glad you figured out you need to recalculate your daily intake. That’s brutally low.
But I want to point out: IF doesn’t technically put you in a calorie deficit in and of itself. Ignoring TDEE for the sake of simplicity here, but if you fast for 18 hours and then consume 2,000 calories, you’ve still consumed 2,000. The act of IF doesn’t magically change that 2,000 calories to 1,800 calories.
What makes IF work for so many people is that when you commit to a window and stay within that window, you are likelier to find it hard to eat ALL of your day’s calories within that window (assuming you’re not inhaling a pizza and focusing on better food choices.) Additionally, IF can help you change where your body is getting energy from in its fasted state, depending on how long you’re fasting and what you eat in your feeding window (ie, ketosis, which you can maintain if you opt for a low carb diet when you are eating.) Keto isn’t required for IF, but I find they work together wonderfully because I’m sated for the vast majority of my fasting window, and the hunger I do have is very manageable (it’s more like “Yeah, I could eat,” to “Oh, I’m hungry.” And passes quickly for me. As opposed to “I’m starving and we have 30 seconds before I hit mass-murderer territory.”)
VLC (very low calorie) diets – around 800 cal/day – are extensively studied (with various eating styles including IF) and generally safe…for up to 12 weeks. [Studies often run 12 weeks, so that’s as far as they’ve looked.] Mind you, those are medically supervised and SHORT-TERM.
The amount of deficit is your TDEE (total daily energy expenditure) minus what you eat. A deficit of 500 cal/day corresponds to 1 lb/wk of fat loss. 1000 cal/day would be 2 lbs/week. So, if your TDEE was 2,500 cal/day, to loss 1-2 lb/wk you would eat 1500-2000 cal/day.
There are several TDEE calculators on the internet. Always underestimate your activity level as this is often inflated for most people. The first couple weeks there may be a lot of water weight lost, but after that, you should eb able to tell how well your TDEE estimate reflects your needs. Don’t forget to recalculate your TDEE as you lose weight (less YOU means less energy needed).
IF makes it easier to reduce calorie intake by limiting your eating window. Lower carb can help you feel less hungry. Together, they can allow you body to move into ketosis (fat burning)and stay there longer – which will help keep your metabolism UP (versus simple calorie restriction with the “three meals and 3 snacks” model which prevents your insulin from having a chance to drop, motivating your body to lower it’s energy expenditure/metabolism).