Welcome to The Fast Diet › The official Fast forums › Body › Weight loss › Fast 800
This topic contains 1 reply, has 4 voices, and was last updated by LJoyce 1 week, 2 days ago.
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27 Jan 21
Hey there, is anyone doing the Fast800? My starting weight was 250lb, I’m about 5ft 8 I think. I started 2 weeks ago on the 13th, so far so good, lost 13lbs the first week, thrilled but also aware that 1st week of any diet is often a higher weight loss due to water, weighed in this morning and another 6lb down. I have a Fitbit and use the app 2 track my calorie intake, I enter everything even lettuce 🤣 and haven’t gone over 800 calories, I have also been drinking around 3 litres of water a day. Also doing intermittent fasting 16:8 only eating after 11 and no later than 7. I have also been walking around 4 miles about 5 mornings a week. I still have a very long way to go but so far I am enjoying the diet and being on furlough at the minute I have the time to concentrate on getting into good habits, hopefully when I get back to work I’ll be in good routine that I can carry on. I see on the forum lot’s of people doing the 5:2 which is great and I hope if I’m happy with my progress after a while to move to it. Just wonder if anyone else is following the fast 800, and if so how they’re getting on.
28 Jan 21
planning on starting fast 800 on Monday – was going to do it this week but pulled an all-nighter for an essay that stupidly I had left mostly until the last minute so food was my friend this week
24 Feb 21
Hi there Cleopatra-i hope your fast 800 diet is still going strong? Im 10 days in and I’ve lost 5lbs hopefully not all water. I’m only sticking to the 800cals 5 days a week and doing lowish carb med diet the other two days as I feel that’s maintainable for the 12 weeks .Ive upped my activity so I get at least 30min of some sort of heart raising exercise a day. Kettle bells or exercise bike are my current go to’s.
So far so good. I’m really enjoying a reduced carbs diet – not super low though as pulses and fruit as so healthy. For once in my life I’m no longer grazing constantly. I had little sucess with the 5:2 and may have found my perfect diet with this 5:2 fast 800 approach.
I’m interested in how others are doing with the fast 800/ full or modified to suit them too.
25 Feb 21
Rapid weight loss is normal in the early weeks.
I lost over 50kg a few years ago and since then have used 5:2 (with <500cal FDs) to maintain my weight. However if my weight goes up by a few kilos I tend to use Fast800 until I’m back within my preferred weight range. I find the discipline of 800 cals every day (and an absence of all treat foods and simple fresh food choices) helps me get back to my preferred weight and also into better eating habits. It’s usually because I’m eating treat foods too often or eating out a lot that my weight rises.
The rapid weight loss when you initially begin a low calorie program is (I’m sorry to say) mostly water and if you are restricting carbs you will also lose your glycogen stores. To get an idea of how much of your losses are likely to be body fat, there is a formula. You need consume 7700 calories less than your body requires for maintenance (TDEE) to lose one kilo of body fat. If I am active (about 80,000 steps a week) my TDEE is around 1800 calories. On fast800 that means I am cutting back approximately 7000 calories per week so the most body fat I will lose is around a kilo. Recently my weight went up so I did a fortnight of Fast800, I lost 2.8kg in the first week and 1.6kg in the second, which brought me back to my preferred weight. Of the 4.4kg lost, I expect just under 2kg would have been body fat.
Once you have been on Fast800 for about a month your weight loss should settle into a steadier pattern and lower weekly weight loss that is all body fat.
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