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Talk to Michael Mosley about Intermittent Fasting, Wednesday 23 January, 12pm - 1pm.

166 replies

RachelMumsnet · 21/01/2013 13:10

On Wednesday at 12pm midday Michael Mosley will be joining us for a webchat and to answer questions on Intermittent Fasting (also known as 5:2 diet).

Michael is a medical Journalist whose BBC Horizon Programme in August last year first introduced the UK to Intermittent Fasting. His latest book The Fast Diet presents the science behind the diet, whilst his co-author, Mimi Spencer explains the practicalities and how to go about it. The idea behind Fast Dieting is that you eat normally for five days and then then consume just 500 calories (women) and 600 calories (men) on two fasting days each week.

If you're interested in finding out more, join Michael Mosley on Wednesday 23 January at 12 midday or post a question to Michael in advance here.

Mumsnet Academy is now offering you the chance to join 5:2 The Fast Diet Course with Michael Mosley, a one day course in Central London on Friday 15 February. Book your tickets

OP posts:
hippoherostandinghere · 21/01/2013 20:04

Hi Dr Mosley, just want to thank you so much for introducing this way of life to me. I never would have believed how much my eating habits could change.

I haven't told anyone though about doing the 5:2 plan (or 4:3 as I've being doing) only my DH. People seem to have a negative view on 'starving' yourself, and think it's another fad diet. What would you say to anyone who challanged the WOE in that way?

Disclaimer I don't believe its starving yourself or a fad, but I think others might view it as that before researching all the details.

plus3 · 21/01/2013 20:05

Hello - apologies I have not read your book, but my DH & I tried the diet following the BBC program. He did incredibly well on the ADF & I tried the 5:2.

I have ulcerative colitis & was wondering if it does indeed have a significant impact on inflammation in the body, and what are the benefits for the autoimmune system?

My problem was psychologically I found it difficult to not eat & wonder if this was due to being in the correct BMI range.

Basically - should I try again for the health impact? A lifetime of immunosuppressants and potentially steroids is not an attractive option!

Many thanks

catsrus · 21/01/2013 20:18

another grateful viewer of the original horizon programme here! 25lbs lost since August and only a few lbs away from moving into 'maintenance' mode. I've found not eating until later in the day has become my preferred pattern (apart from the odd miso soup Grin). I have found it positively mood altering and energizing - counter intuitive for most people but true for lots of us.

From what I have read there are two separate things involved in the health benefits and weight loss. One is the calorie restriction to 500 on a few days a week, the other is the length of time without calories (the whole restricted 'eating window') in any given day. Clearly I've cracked it in terms of weight loss so now I'm looking more closely at long term health benefits. My diet is already primarily plant based and healthy (I was just eating too much of it Blush) and I don't have much of a sweet tooth (Just hide the interesting bread and cheese!).

So a couple of questions

  1. how negligible does the calorie intake have to be to count as "calorie free" (do I have to bin the miso soup and drink my tea black?)
  2. from the research you have seen would you consider that moving to a more general "eating window" restricted week might have equal or more health benefits than moving to 6:1? i.e. if I don't eat breakfast (and sometimes lunch) on a more regular basis then I assume my body goes into repair mode more frequently - or is that not the case?

    again - thanks to you and the Horizon team - I have finally shifted the post menopausal weight and can wear my 'smart stuff' again Smile I also feel more in tune with my body and it definitely doesn't feel to me like "being on a diet"!
lovelydahlias · 21/01/2013 20:56

Hello Dr Mosley
Have there been any studies into the effects of the 5:2 on thyroid? I have an underactive thyroid and currently take 100mcg per day. I started the 5:2 diet in August and did it for 4 months. However it made me feel quite unwell - really stressed out, not sleeping, irritable, cold, incredibly hungry on non-fast days and I often had palpitations - all of these effects I also get when I do exercise classes such as spinning, I think my adrenal glands go into overdrive? Yet I'd got so far with it and was very reluctant to give it up (but my family were!). However the longer I went on with it the worse I felt. My husband also did it and continues to and has had none of these problems. Do you think these side effects could be linked to my thyroid?

TepidCoffee · 21/01/2013 21:27

Hello, can I point you to this blog post at Paleo for Women and ask you for your thoughts?

It's a review of female-specific responses to fasting in the literature and makes a really salient point. So much research seems to be based on the male as standard. But women are, physiologically at least, entirely different and it stands to reason that our responses may differ from that of men.

As this site is largely made up of women, it would be useful to hear what you have found out about women specifically, rather than your 'general' findings, which on closer inspection will probably be geared towards men.

Right, now I'm off to read the thread and will probably discover that either a) the whole book is about women or b) thirty people above me have already asked the same question :o.

TepidCoffee · 21/01/2013 21:29

Lesbea check out the blog I linked to, I think you'll find it really useful.

iclaudius · 21/01/2013 21:58

Michael - my husband and I both 45 seem to live by this mantra and were delighted to see your program give it some credence.
I have had many children but keep my BMI at a steady 20 despite doing a LOT of eating whatever I want.
Are there any long term studies into this - sometimes I worry that we could be doing ourselves some unknown harm!

louise3louise3 · 21/01/2013 22:01

Dear Dr Moseley, I too, would like to know if it would suitable for me. I have an under active thyroid and take 150mcg of levothyroxine per day although often feel exhausted. Blood tests show normal. I gained 4 stone after an operation for spinal fusion and at the same time thyroid problem was noticed. I have been unable to lose weight since except when pregnant with twins losing 2 stone without trying and then piling it all back on after giving birth. I'm pretty desperate - I weighed 8 stone for 25 years and now weigh 12 stone. Help.

bunty1 · 21/01/2013 22:03

Hi there!
I read somewhere that you can also do this diet by eliminating the 500 cals all together twice a week. If this is so, is it possible to fast from say 5pm to 5pm the following day . I figure it would be easier for me this way as you can stop eating at 5pm , go to bed relatively satiated that night and you only have to wait until 5pm to eat again..... I generally don't get hungry until about 2pm so I figure I could do it this way quite easily....but does it affect how the diet works? Thanks!!

KoalaKube · 21/01/2013 22:43

Hi Dr M just wondering what effect anti-depressants have on this way of weight loss. Currently taking 100 - 150mg of sertraline per day. Don't have much of an appetite but drink lots of milky decaff with 1tsp sugar prob 10 cups per day + water or no cal drinks (v thirsty all the time). I'll then have a meal of about 600 cals some evenings when I feel like it (i.e tonight I had 2 lamb chops and some brocolli). I've lost about 8-10lbs in weight in 6 weeks., but have 2 stone to lose to have healthy bmi and not be obese. I can cut out sugar and work harder to have a healthy food intake - just wondering what effect the ADs might have/are having.


claredanes · 21/01/2013 22:50

I did this for a few months last year and found it very easy. I felt good too. Looking forward to the webchat.

SeriousStuff · 21/01/2013 23:06

My husband trains regularly (quite high intensity) and wondering whether it's ok to do so on fasting days as he is burning much more than the 600 calorie allowance.

Thank you!

starlady · 21/01/2013 23:08

Hi Michael, I've been doing 5:2 since Nov, and have lost about 8 lb. I'm now 11 stone 8 lb and 5 ft 11 and 42. I do feel a lot better - more energised, sleeping and breathing better, and mentally sharper. I put on 5 stone in the last 20 years (I was very underweight due to having Marfans syndrome). Which brings me to my question - the only negative study about blood flow to the heart.

My heart is checked yearly and so far so good, it's healthy. I'm on no medication. Haven't discussed with my gp, or seen cardiologist . I'm worried I will get knee jerk response. What's your take on blood flow issue?

IAmNotGeoff · 21/01/2013 23:10

I have been intermittent fasting for four months now and feel great. I have lost 2.5 stone and am heading to a much better weight (I'm a 42 year old man currently 15 stone).
However, when I fast I am more frequently getting a headache. It's always to the left side of my head around the sinus area. Is there a connection and is there anything I can do about it?

duchesse · 21/01/2013 23:26

Hi Dr Mosley (my friend used to go out with your brother D by the way, about a 1000 years ago), I've been doing the 5:2 for nearly 4 weeks now, respecting my recommended intake of calories on my non-fasting days, and have actually gained half a kilo in that time. On a fast day I have very occasionally dipped down 500g but essentially my weight has remained the same. I am at the very upper edge of the healthy range in terms of BMI and could stand to lose 10 kg as I have a very slender frame. Where am I going wrong?

duchesse · 21/01/2013 23:29

I forgot to say that in common with other posters I have an underactive thyroid- not massively so as I'm only on 50mcg/day, but I do wonder if underactive thyroid may be the downfall of the 5:2 method? I feel otherwise well on fast days (in fact not really particularly hungry until about 20 hours into complete fast) and have plenty of energy.

NatashaMousse · 21/01/2013 23:46

Thanks so much for the excellent Horizon programme, Dr Mosley.

Being in the extra-lean category, I am doing 6:1 for the health benefits (one 32-hour no-calorie fast per week and extra calories on other days to avoid weight loss). From the start I've experienced improvements in energy, mental clarity, and general disposition, but have not had blood work done. Can you share with us the results of your tests doing 6:1 as compared with 5:2?

If I may, I would like to second the request for answers to the questions about HIT without equipment, the anti-inflammation effects of fasting, and an eating "window" (daily or several times a week) vs. 6:1 for both health benefits and weight control.

Ezzza · 22/01/2013 05:58

Dear Dr Mosley,

All my questions have been asked by others already, so I just want to say thanks for bringing this way of eating to the public?s attention. (No question in this post, just thanks, so you can skip it if running low on time.)

After a longish spell of illness I found myself just squeaking into the obese category without the mental energy to do the only method I?d ever had success with in the past: daily calorie restriction. A friend saw your program on Horizon and told me about it. I was sceptical but I watched it and thought I?d give it a go.

20 weeks on I?ve managed to lose 24lbs and BMI is down to 26.1 so far. I?m still finding this way of eating really easy to stick to and even managed to keep going through a weight loss plateau, which I?ve never managed to do before and the weight is coming off again now. Better than that though, I?m feeling much healthier than I did last year (problems with anxiety and sleeplessness significantly reduced).

I have no doubt that if it hadn?t been for the Horizon program that aired in August I?d be even bigger now than ever. Thanks for helping me to no longer be obese! Thanks

Breadandwine · 22/01/2013 07:46

I'm a 75-yr-old male, been practicing IF since last Feb, and I was delighted to see your programme back up all I'd read.

My question is: If we've completed a 24 hour fast - from 6pm until 6pm the next day, say - why do we then have to restrict our evening meal to

ManateeEquineOhara · 22/01/2013 08:02

Some questions for later as I'll be at work when this is on:

Why are you advocating weight loss? A number of studies are showing that with he exception of extreme morbid obesity, the health risks are pretty ambivalent, with some studies showing those in the overweight category living longer than those who, following the BMI, are classed 'healthy'. (For example the recent review and meta analysis from the Journal of the American Medical Association by Flegel, 2013.). And others illustrating the subjective nature of statistics which suggest overweight and obesity is unhealthy (eg Ernsberger, 2009, Gaesser, 2009 Gard and Wright, 2005, Campos, 2004).

As I am sure you are aware, people with eating disorders are highly likely to listen to, and practice what you are recommending as a way to loose weight further (possibly 'tweaked' to their usual patterns of eating 5 days followed by even more severe restriction over 2 days). How are you going about ensuring that your 'diet' remains as un-triggering as possible?

Stellightful · 22/01/2013 08:20

Hello Michael
I've loved reading the book and I have my 3rd weigh day tomorrow and hoping that I will have lost 5 or 6 pounds in that time. I know a lot of it is water but see this as a long term way of life that I can do. So thank you!

Anyway my question is in relation to the 5 eating days. Do people and did you go up to the recommended calorie intake (so 2000 for me, 2500 for you) on those days? It just seems too much and I feel that the weight will go on in those days (and from a sneaky look on the scales that is what is happening). What do others really do? There's not much talk about this and I wondered whether you thought it better to still stick to a 1200 say calorie restriction on the 'feed' days. My BMI is just under 30 so I have a few stones to lose. Many thanks.

Illuminata · 22/01/2013 12:30

Hello Dr Mosley
Thanks for coming on MN
Am an apple and I am overweight, not obese but would like to lose 1.5-2 stone.
BUT I am thinking of trying to conceive in the next few months too.
Would this way of eating be a bad idea?

MustGetMoreExercise · 22/01/2013 13:03

In your book you mention that there are human trials being run looking at the impact of fasting on cancer, in particular will fasting improve the efficacy of chemotherapy and radiotherapy. Have you any update on these or do you know when the results will be published?

I'm interested because my husband had radiotherapy for prostate cancer 6 weeks after starting the 5:2 diet with me when we saw your Horizon programme. He has just had a PSA test and the result has dropped significantly - more so than the surgeon expected at this stage. We are obviously delighted.

tomorrowweeat · 22/01/2013 13:26

Please could you explain why this diet is not suitable for type 2 diabetics. Also should Metformin dosage be lowered on fasting days?

androbbob · 22/01/2013 13:28

Is this diet ok for type 2 diabetic who needs to shift at least 2 stone of weight. Diabetes is diet controlled only and has been for the last 5 years, but this will change as I get older if I do not shift the pounds. Any thoughts?

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