The FastDay Forum

There is headline report about the dangers of a high protein diet in the Daily Telegraph today
http://www.telegraph.co.uk/science/scie ... oking.html

I wondered if any of our Medical research people had any comments?

Hi Sian

Was just going to post about the same report in the Times. Would also be interested in hearing what others think. From the quick scan I gave the article, not the paper, it seems to be talking about Atkins and other more extreme carb restricted/hi protein diets.

[carorees]

This was a major part of Dr M's documentary and book: that too much protein raises IGF1 and that IGF1 is associated with cancer. The studies on longevity and calorie restriction are finding that in primates, as well as calorie restriction, protein needs to be limited too for the increase in longevity that is seen in lower animals with calorie restriction alone.

So fasting and protein restriction is likely to be found to be best for longer life. Much of the benefits of fasting come from the lack of carb intake during fasting, so we can add lowering carbs to our list. This leaves fat to make up the balance of calories.

IGF1 acts on a cell pathway known as the mammalian target of rapamycin (mtor). Mtor is a nutrient sensing pathway and is also stimulated by high blood sugar. Mtor stimulates cell growth and all the things that cancer cells do. By contrast, low sugar and low IGF1 stimulates another pathway called forkhead transcription factor (FOXO). FOXO stimulates cell repair, autophagy and programmed cell death...all the things that cancer cells don't do.

There's a fair bit on Mtor and foxo in the lab from earlier last year...

Must be a conspiracy as the Mail is also pushing it. Personally, I am happiest and feel better on a lower carb and reduced sugar, low to moderate protein and high fat diet. Not sure if it is the best combination but it seems to work for me.

Ballerina x

This same topic was in the radio today. An Australian study has shown that a low protein, low fat and high carbohydrate diet is the best for longevity. I'd link the report but no idea how to on my phone. They did say this is basically a vegetarian diet.

There's another study today, published in cell metabolism by an Aussie group, feeding mice as libitum with different combinations of macronutrients. I've been trying to post the link, but sorry, I can't get it to work. But I found it by googling cell metabolism journal. I'd love your opinion, @carorees, as it seems to show on the surface of it that low protein high carb diets are associated with the longest lives - but they are mice! They talk about mTOR in this one too, but it's a bit too complex for me to reach any discerning conclusions with only my one pair of brains, that's why I need yours, Caroline!

[Debs]

Just popped up on the ABC here too. The mice who ate high protein died young, those who ate low protein and high carb lived longer and were fatter. You just can't win if you're a mouse!!!

That's probably the same one I heard Debs

So what counts as 'low protein' then? I think I eat too much.

[Debs]

At least those mice don't get bombarded with conflicting information all the time, they just eat what they are given. Blocking ears now! I guess by fasting we are limiting everything to some extent.

[carorees]

You have to remember that mice have not evolved to eat meat and so weighs be executed to do better on high carb low protein whereas we've evolved too easy an omnivorous diet and so I would expect that a higher fat lower carb diet with medium protein would be more biologically appropriate. I think that the primate studies are where we should be looking, not mice tbh.

Jools, can you give me the citation of that paper so I can look it up?

The Ratio of Macronutrients, Not Caloric Intake, Dictates Cardiometabolic Health, Aging, and Longevity in Ad Libitum-Fed Mice
Cell Metabolism, Volume 19, Issue 3, 418-430, 4 March 2014
Copyright © 2014 Elsevier Inc. All rights reserved.
10.1016/j.cmet.2014.02.009

http://www.cell.com/cell-metabolism/fulltext/S1550-4131(14)00065-5
Hi @carorees, hth!

Channel 4 recently re screened an old programme on Atkins. It's a pity they did not update it. I'm with @ballerina. My fat intake is frequently 45% and more of what I eat. I would rather keep my protein low than carbs given a choice but certainly no sugar.

In my morning paper they said that this was for people under 65 (not sure exactly which amount of years) and that elder people benefited from a high protein intake. Strange - wonder how they realized this??

Please don't hit me - but if we go low-carb, plow fat and low-protein, what on earth do we ought to eat? Just veggies? I refuse

[carorees]

Don't go low fat is the answer!

Re age, it is known that low IGF1 levels are associated with frailty in the elderly, so for them it is best to have a reasonable protein intake.