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Combining fasting with low carb 1

(331 Posts)
StuntNun Sun 07-Feb-21 14:21:28

This thread is for people who want to combine fasting with a low carbohydrate way of eating such as Low Carb Bootcamp, keto, paleo or primal.

Disclaimer – I am not a health professional – I am relying on my own reading and experience. If you have a relevant health condition then consult your doctor before introducing fasting. For example, people with diabetes or high blood pressure often require medication adjustments if they cut carbs or start fasting. In many conditions, medications must be taken with food which may dictate one or more regular meals per day. If you have had an eating disorder, or tend to be obsessive or controlling about food, then fasting may not be appropriate for you. I’m happy to chat about any of these issues but this thread is not a substitute for professional medical advice.

Why fast?
1. To lose weight
2. For the health benefits (e.g. reducing insulin resistance, triggering cellular repair, lowering inflammation, reducing blood pressure)
3. All of the above!

Types of fasting
1. Intermittent fasting (for example 16:8)
2. Fasting mimicking diet (such as 5:2)
3. Extended fasting (over 24 hours)

I will describe each of these over the next three posts. Most people start out with, or working towards, either 16:8 or 5:2. Before we get started, my top fasting tip is to make sure you have plenty of calorie-free drinks: water, black coffee or tea, green tea or herbal teas. You may need to drink more than usual because you aren’t getting any water from food during your fasting window.

OP’s posts: |
StuntNun Sun 07-Feb-21 14:21:49

Intermittent Fasting

16:8 involves fasting for 16 hours overnight. So if you finish dinner at 7 p.m. then you don’t eat again until 11 a.m. the next day. This means you have a 16-hour fasting window and an eight-hour eating window. You should find that you feel hungry at your normal breakfast time but within half an hour the hunger has faded again. A big drink of water or a cup of coffee or tea can help get through the temporary hunger. You won’t get hungry again until your normal meal time so don’t worry, you won’t spend the fasting window feeling constantly hungry. If you have trouble fasting for 16 hours then start with 14 hours (14:10) and work up to 16 hours gradually.

If you’re new to intermittent fasting then aim for three fasts a week at first and increase the number when you feel ready. Some days you will feel hungrier than others and you will still want to have breakfast, even once you’re used to intermittent fasting every day.

Many people allow up to 50 calories during a fast period so they can have a cup of tea or coffee in the morning then eat a late breakfast. Some people drink bone broth, coffee with cream, or butter coffee during their fasting window. These can be useful aids for introducing fasting or lengthening your fasting window. Fasting get easier very quickly over time so you shouldn’t need these crutches for long.

You can eat as many times as you want within your fasting window. I started out with three meals then over time moved to two meals, sometimes described as TMAD – Two Meals A Day. You can also experiment with different eating windows; 20:4 (sometimes called the Warrior Diet) is popular.

OMAD – One Meal A Day is a popular approach for weight maintenance but isn’t as good for weight loss. It can work well, especially for the first few weeks, but for some it is impossible to eat enough calories for a day in a single meal so eventually weight loss stops.

OP’s posts: |
StuntNun Sun 07-Feb-21 14:22:07

Fasting Mimicking Diet

The 5:2 diet has been widely promoted by Michael Mosley. On two non-consecutive days you eat 500 calories (600 for men), either as a single meal or in two or more snacks. If you’re following a low carb high fat way of eating then you will need to reduce your fat intake on fasting days. The other five days a week you eat as normal.

If you find it too hard to stick to 500 calories then you might try the New 5:2 which is 800 calories on two days a week following a Mediterranean-style diet.

Once you have got used to 5:2 you can increase your number of fasting days to three a week or even every other day, this is modified ADF (Alternate Day Fasting.)

Michael Mosley’s Very Fast 800 is an intensive low-calorie Mediterranean-style diet. In my opinion it is really only for people who need to lose weight extremely quickly, for example if they are at risk of medical complications or need to be under a certain weight for an operation. You can easily lose the same amount of weight over a slightly longer period without needing to be strict about calorie restriction.

OP’s posts: |
StuntNun Sun 07-Feb-21 14:22:52

Extended Fasting

Extended fasts are over 24 hours and aren’t actually as daunting as they sound. When you’re used to 16:8 fasting you may find yourself accidentally skipping lunch and end up having a 24-hour fast from dinner one day to dinner the next. (Note this isn’t the same as OMAD which is where you only eat once a day, every day.) If you’re used to 16:8 and want to extend your fasting you can add one, two or three 24-hour fasts a week. 24-hour fasts are a good approach when balancing family life since you can eat dinner with your family every day. The Eat-Stop-Eat diet has two 24-hours fasts per week.

The next option is a 36-hour fast where you eat dinner on day 1, fast for all of day 2, then eat breakfast at your usual time on day 3. Dr Jason Fung recommends Alternate Day Fasting with three 36-hour fasts a week, combining 16:8 with longer fasts. So you eat lunch and dinner on Saturday, Sunday, Tuesday and Thursday, and nothing on Monday, Wednesday and Friday. As with 16:8, some people drink bone broth, coffee with cream, or butter coffee to help themselves get through these longer fasts, although eventually you shouldn’t need them.

Some people extended fast for even longer periods such as 48, 72, 96 hours or even up to 30 days! The longest recorded fast was 382 days however it was performed under medical supervision and required frequent hospital evaluations. For fasts over 48 hours there are additional concerns such as micronutrient intake (you can take multivitamins but they won’t be absorbed well if not taken with food.) With very long fasts your digestive system shuts down which can lead to problems when you do start eating again. People who extended fast only do so occasionally for example once a month to once a year. Extended fasts are probably beyond the scope of this thread; I expect most people will be interested in 16:8 intermittent fasting.

So let’s get started! What do you want to talk about?

OP’s posts: |
Gotheeunicorns Sun 07-Feb-21 14:34:02

Hi. I'm sort of doing this already. I do 5:2 on a Monday and Wednesday and generally eat low carb the rest of the time except for Friday nights where I'll have whatever I like for dinner. Only been going a few weeks. The scales say I've lost 2lbs but my clothes are much looser and I am definitely more toned - I've been doing a mixture of weights, body weight circuits and running. I am determined to be comfortable in a bikini by summer.
Today so far I've had:
B: oats, Greek yoghurt and blueberries
2 cups coffee with milk
L: 2 slices sodium free bacon,2 scrambled eggs with spinach and mushroom with lots of raw spinach.
Also had a square of 85% chocolate.
Dinner will be a meat based curry.
I need to drop the oats down a bit but I have felt really sated all day. I also can't drop the coffee.

AtlasPine Sun 07-Feb-21 14:34:26

I’ve been doing 3x 36 hr fasts a week (8 weeks), a break of a month then 2x36 hr fasts a week plus an 18 hr fast for another month so far. Low carb throughout. Reversed my prediabetes and lost 4.2 stone so far. It is workable but I will have to find a maintain lifestyle level when my weight is where I want it to be. So continuing for another two months like this, then will probably go for long term 18:6 on weekdays. It’s a balancing game!

AtlasPine Sun 07-Feb-21 14:37:57

But I think the low carb plus some level of fasting is the way forward for most of us. There is so much evidence pointing towards this as a way of reducing the inflammation behind so many chronic conditions.

Oneborneverydecade Sun 07-Feb-21 14:57:43

Thanks for the thread @StuntNun

I'd been doing 18:6 for some time and lost 4st but my progress had slowed, so this week I've tried to stretch it to 20:4. I'm 3lb down so far.

I might also add in a 23 hour fast one day, so evening to evening

Looking forward to learning more and sharing our progress

cheeseisthebest Sun 07-Feb-21 14:58:47


cheeseisthebest Sun 07-Feb-21 15:06:08

I'm doing low carb boot camp (and love it!). I've lost half a stone since beginning of Jan and often doing 16:8 which I couldnt have done before changing my way of eating. I probably do it 4 or 5 times a week?

Almahart Sun 07-Feb-21 15:36:03

Thanks so much for this @StuntNun, I've been doing 16:8 really easily this boot camp but would like to extend my fasting period so this thread will be really helpful.

StuntNun Sun 07-Feb-21 16:06:19

Oneborneverydecade it's good to mix things up to try and prevent/limit weight loss stalls. The body prefers a steady state so if you're doing 16:8 throwing in a 24-hour fast will help stop your body adapting metabolically to 16:8 to maintain the steady state. Equally I like to throw a breakfast in every now and then so my body "knows" there's plentiful food available and it's okay to let go of excess fat reserves.

cheeseisthebest four or five times a week is plenty to get the health benefits of fasting.

OP’s posts: |
stilllovingmysleep Sun 07-Feb-21 16:16:00

I lost a significant amount of weight over the last years. I'm maintaining quite well and now pushing to lose the last 3-5 kg

What worked
Initially I did a stricter low carb diet which really deals with hunger well. That was for about a year.

However after a while I didn't find it sustainable nor did I want to live that way forever

I now mostly eat low carb; but often have my main meal at lunch and then skip dinner and eat again at breakfast next day (I guess that's the 16:8 approach?). I do make exceptions to low carb eating nowadays

Two strategies that have hugely made a difference for me though are
--writing down a plan of eating for the day each and every day based on what's doable and realistic each day and what I want to eat
--"riding through" food cravings as much as possible (I don't always manage) by having some water and setting a timer for 15 min. 8 times out of 10 craving has gone by the time timer is up

stilllovingmysleep Sun 07-Feb-21 16:16:48

Not sure why a sentence was struck out!
That bit (writing down a plan) crucial for me each day

stilllovingmysleep Sun 07-Feb-21 16:17:18


Oneborneverydecade it's good to mix things up to try and prevent/limit weight loss stalls. The body prefers a steady state so if you're doing 16:8 throwing in a 24-hour fast will help stop your body adapting metabolically to 16:8 to maintain the steady state. Equally I like to throw a breakfast in every now and then so my body "knows" there's plentiful food available and it's okay to let go of excess fat reserves.

cheeseisthebest four or five times a week is plenty to get the health benefits of fasting.

@StuntNun fascinating about mixing it up a bit like that

MarmaladeTeepee Sun 07-Feb-21 16:42:06

Thanks for this StuntNun. I'm joining from the lowcarb bootcamp thread, although I've been fasting a lot longer than doing bootcamp. An ideal week for me would be OMAD Mon-Thurs (out of circumstance more than anything as I'm not hungry first thing and I'm a Teaching Assistant and only get 15 minutes for my lunch. So by the time I've gone to the loo, drank a load of water, checked my phone and gone to the loo again, I don't have time to eat!) Fri would be an extended fast for autophagy and then the weekends would be 18:6.

Like I said that would be the ideal, although both low carb and fasting went out the window last week due to lockdown blues so determined to get back on track next week. I need to keep reminding myself spring is on its way and this won't last forever!

poorbuthappy Sun 07-Feb-21 17:16:20

Hello StuntNun! And everyone else!
I am currently on boot camp but lite as started in Oct and only really had a few meals off over Christmas so have just got back on it.
I do 16:8 prob 5 days a week. But would love to extend this to a 24 hour at least once a week.
Looking forward to getting into it.

venusandmars Sun 07-Feb-21 18:32:48

Thanks StuntNun mostly doing 16:8 or 14:10 but interested in extending to 24hrs (or 23.5 to give me time to eat!)

oscarandelliesdad Sun 07-Feb-21 18:42:33

Hi @StuntNun, thanks for doing this smile I'm low bootcamping over on the other thread too and keen to extend my fasts. I do 16:8 really easily most days and then if I'm busy (especially on the low carb plan) I find that I just forget to eat until late afternoon, the problem is that once I start, I pick at things and feel discontent, I think the 24 hour fasts on the days when I'm out and about will be good to break the nibble habit. Isn't it amazing how the chat around fasting has changed? I remember getting a real lecture for skipping breakfast in the late nineties!

Hopeislost Sun 07-Feb-21 19:31:26

Thanks for the new thread Stuntnun! I've been doing 16:8 pretty much every day since about July and in a bit of a stall so interested to read about mixing it up!

Fagey Sun 07-Feb-21 21:03:22

Hi all.

This may be the perfect thread for me!

I read the Fast800 book 2 weeks ago as I realised just what an unhealthy person I am. sad

How unrealistically and dangerous I was eating day to day. So many carbs. Just whatever I wanted whenever I wanted. And did it make me happy? Maybe for that moment I was eating it, but often not even that.

I'm mid-thirties, 5'4" and after Christmas some days the scales were over 16 stone. sad

Once lockdown III began I started doing Joe Wicks every day with my daughter. And also started 16:8 as I never fancy breakfast much anyway but we'd got in the habit of always have croissants or broiches in the house so would have one with a sugary coffee first thing. Then lunch would always be bread based. And dinner pasta/pizza/wraps/burgers etc with chips.

I hate what I see in the mirror, have the worst self confidence I've ever had in my life, see zero point in clothes shopping - it all looks shit.

I've had to take my blood pressure the last few months for medication I'm on. Of course it's higher than it should be for someone my age.

Got a blood glucose monitor and surprise surprise I was pre-diabetic with my fasting readings and after a meal of sweet and sour chicken (unless Ben's jar of course) and white rice my blood sugar was nearly out of the pre-diabetes range and into diabetic levels.

So last Thursday I started F800. Have been making a lot of my own meals as trying to match them as best I can to what I'm cooking the family.

My blood glucose and pressure are already lower. And today I weight 15st3lb.

Still a long way to go. But this is the first time I've seen a way of eating as for my health rather than for my figure. And ultimately I think it's a much stronger motivator.

Fagey Sun 07-Feb-21 21:07:28

My previous post was super long and boring.

But here's my general diet plan currently:

Fast 16:8 (although normally it's closer to 17:7)

8pm-1pm fast. Lunch at 1pm. Dinner at 6pm and then sometimes a cup of milky tea after.

- 800 calories a day.
- under 40g carbs per day
- at least 60g protein per day.
- all whole foods, cooking from scratch.
- no snacking between meals.

Today I had prawn salad for lunch (made the dressing with Greek yogurt, lemon juice, tomato purée and a little Worcestershire sauce)

For dinner I made burgers from beef mince, onion, garlic and carrot. And had them with 30g cheddar on top, lots of gherkin, salad and celeriac chips.

Fagey Sun 07-Feb-21 21:21:24

@stilllovingmysleep - how often do you shake up the 16:8?

Your post was very interesting!!

StuntNun Sun 07-Feb-21 21:33:52

Well done for making such a good start Fagey you seem to have everything well in hand. I don't think I could manage 800 calories a day, how are you finding it? In response to your question to stilllovingmysleep I do 16:8 most days with an extended fast once a month.

OP’s posts: |
LostaraYil Sun 07-Feb-21 21:41:47

Thank you StuntNun! I'm another boot camper. I usually do 16:8 during the week and have breakfast at the weekend with DH. I did one 24h fast this week and am going to try to do 24-36h once a week. I'm not far from target weight so I want a boost to weight loss and am also curious about the other benefits from fasting. At the moment I also like the idea of just mixing it up for a challenge, any change from my groundhog day existence is a good thing.

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