The FastDay Forum

The Two Day Diet in the Daily Mail was initially produced by a Doctor who is quoted in Michael Mosely and Mimi Spencer's book. I've done a read online about it, and it's more or less the same from what I can gather, though it recommends two consecutive days of fasting.

I'm glad to see there's additional research being done on this style of 'dieting' and a little healthy rivalry probably won't hurt It'll also be interesting to find out what the 'best' method is but...

I've dieted many times before and I know for a hard fact that I will fail in any diet that requires me to be careful or make dietary choices every single day. My diet is improving as a matter of course by intermittent fasting (more fruit & veg etc). It'll be easy to say that a two day fast with a Mediterranean style diet is the right way to go but for me personally it probably just won't be sustainable in the long run.

Whats working for me so far with the 5:2 diet is that the whole approach seems to be one of 'here's a diet/way of life that's beneficial to you and requires only two days out of every seven of effort'. It's probably more important that a diet is sustainable and can genuinely become a way of life...

Just my two pennies worth

James

I agree absolutely with your comments James. As soon as every day calls for special attention, I know for a fact I'm done for! Whereas I can easily cope with just 2 days per week of effort and actually look forward to it in a strange sort of way...

Weight loss is one thing (of no interest to me). What I'd like to know is whether restricting carbs alone can lower IGF1. From the explanations in the book it seems that having a high protein intake would allow cells to carry on dividing in their normal way. If low carbs really does the trick then you'd have to ask why the establishment was so dismissive of Atkins a decade ago.

PaulM, I suspect that IGF-1 has not been the focus of Dr Harvie's research, because her previous 'Milk Diet' did not reduce IGF-1 (unsurprisingly I think because it required participants to drink so much milk!), and the research for the new diet shows that it doesn't either (see links above). Dr MM did find his IGF-1 reduced by following his 5:2 (on the Horizon programme), but with a sample size of 1 this is hardly scientific proof.

I too would like to know more about reducing IGF-1, including whether it really matters. There is an argument that it is perhaps trivial or irrelevant and we should focus FoxO (which can't be measured, unfortunately). It is only one of the non-weight-related benefits of 5:2, and it is the one about which there seems to be the least consensus...

http://www.ncbi.nlm.nih.gov/pubmed/10506632 says "We observed that serum levels of IGF-1 are positively associated with consumption of red meats, fats, and oils. In addition, serum levels of IGF-1 are independently and positively associated with energy intake from lipids and negatively associated with energy intake from carbohydrates. Finally, serum levels of IGFBP-3 are independently and negatively associated with energy intake from saturated fat." - which would argue for high carb low fat low protein if seeking to reduce IGF-1. It was a bit observational though.

A similar type of study found "No independent associations of dietary factors with IGF-I or IGFBP-3 concentrations were observed." - http://www.ncbi.nlm.nih.gov/pubmed/15456992

a bit more light reading extracted a conclusion "Increasing the protein content of the diet from 15 to 30% resulted in an 35% increase in IGF-I regardless of whether the carbohydrate content was 40% (14), 20% (Nuttall and Gannon 2005), or 30% as in the present study. Thus the dietary protein-induced increase in IGF-I is independent of the amount of dietary carbohydrate and fat." - http://carbsanity.blogspot.co.uk/2011/0 ... tor-1.html

Enjoy.

Thanks Phil: interesting - and confusing. No one seems to have looked at a possible connection between milk specifically and IGF-1. It seems logical to me that there would be a positive correlation because milk is 'baby food' for calves, whereas other forms of protein (vegetable or animal) would, historically and in evolutionary terms, be consumed by adults as well. So my theory (based on no evidence at all) is that the identified positive association between protein and IGF-1 is actually a connection between milk (and related products) and IGF-1.

The finding of the recent Dr Harvie trial that the new 2D did not reduce IGF-1 despite being low-carb would suggest that carbs are innocent on this occasion.

Colostrum or first milk after birth is apparently high in IGF-1 directly -

"IT HAS BEEN SHOWN THAT BOVINE colostrum supplementation increases serum insulin-like growth factor (IGF)-I concentration in male athletes during a short strength and speed training period"

"IGF-I is a major form in bovine colostrums, and the concentration is 7–67 nmol/l (40), whereas normal milk contains <0.3 nmol/l "

http://europepmc.org/abstract/MED/16423633 found a significant increase in IGF-1 on a high protein diet which did have 5 ozs of cheese per day but plenty of egg, ham, tuna etc.

[carorees]

There is a researcher in Germany who has published several papers on the connection between milk and acne and in at least one he has reported higher IGF1 in people who drink milk: www.ncbi.nlm.nih.gov/pubmed/19709092

Thanks all. My take away from all that is that protein restriction on my famine days (as I prefer to call them) should be a good strategy to minimise IGF1. Not scientifically watertight, but makes sense (eg body builders consume loads of dairy based protein to build muscle - requiring cell division).

I should probably apologise for dragging the tread OT, but for me this issue rules out the Harvie variation. I also agree with other posters requiring 7 days attention would be a major drag, even if I do generally try & eat well (according to the current advice of the time....) Then again I'm genetically unlikely to get breast cancer (!), so probably not in the 'target' audience.

[carorees]

I should point out that Dr M recently adviced on twitter that one should reduce protein on feast days not on fast days.

I should point out that Dr M recently adviced on twitter that one should reduce protein on feast days not on fast days.

He did that when he was on holiday and I wasn't convinced he got it the right way round - is this more recent ? I think he should do a blog post to clarify as it's as clear as mud currently. As he claims to be "evidence based" I would expect him to be following Varady's line of <30g protein on fast days.

Also, 30g protein, I would think is not the total weight of the piece of meat, fish etc. If you look it up 120g of beef has approx. 30g protein if roasted, steak for the same weight has less than 20g protein, salmon (oily fish) has approx. 25g in only 100g weight. Obviously different meats, fishes etc. all have varying amounts of protein per 100g total weight.

[carorees]

The protein reduction is required on feast days as it is the excess protein every day that needs to be reduced. On fast days the calorie restriction takes care of it, on feast days we need to be more careful. Aim for less than 60g per day for a 70kg person.

Also, 30g protein, I would think is not the total weight of the piece of meat, fish etc.

Of course, 30g is the amount of protein, not the amount of food that contains the protein.