Hello

I read a lot of stuff, in the last few years, about calories restriction so much that I became an ardent follower until recently when I finished to read the following book

http://intensedf.com/Content/Health/Book/WhoShoulReadThisBook.aspx



This book states that the effect of calorie restriction is not related to the restriction of calories but to the fact that with calories restriction we are actually doing a Methionine restriction that is the real cause of the benefits we get from this practice.



On top of that, it states that the French paradox can be related in some way to the Methionine.



If the book is right we do not need to starve ourselves to get all the benefits of the calorie restriction but it is just enough to reduce the quantity of Methionine in our diet.



I decided to follow this new approach because despite been very interested in getting all the benefit of caloric restriction I find some times very hard to stay on a low calorie diet .



I just started few weeks ago to reduce the quantity of Methionine in my diet and I have increased the quantity of calories to remove the feeling of starvation. I hope this will allow me to get the same benefits with much less pain.



What do you think about my choice? Who agrees with my choice and who does not? And why?



Any advice is welcome



Thank you

So no one is on a methionine restriction??

that is strange with methionine restriction you get same results as CR with less hassle

Methionine restriction decreases mitochondrial oxygen radical generation and leak as well as oxidative damage to mitochondrial DNA and proteins
Sanz, A., Caro, P., Ayala, V., Portero-Otin, M., Pamplona, R., Barja, G.
FASEB J. 2006; 20:1064-1073. [Abstract] [Full Text] [PDF]

While this analysis of the data is repeatedly advanced by the main researchers involved, it remains, at best, an unproven hypothesis -- and until firmed up, it's a dangerous distraction.

french paradox is not due to methionine restriction? they eat lots of foie gras,fish,meat,cheese which all contain a lot of methionine

That is true but they also drink a lot of wine (alcohol)

The author of the book that I read says that our body uses Methionine to destroy alcohol in the alcohol metabolism.

This could explain why a moderate quantity of alcohol is good.

The French paradox is: French people eat a lot of animal food as many other population buy because they drink a lot of wine the alcohol in this wine reduces the damage caused by the large quantity of Methionine this is why they have less problems.

We can summarise this with

High animal food diet >>>>> large quantity of Methionine = high damage

High Animal Food diet + alcohol >>>> small quantity of Methionine because it is used to destroy alcahol = less damage

(in animal food the quantity of Methionine per g of protein is 3 times what can be found in vegetables-fruit this could be another reason why animal food are so unhealthy)

It is true that Methionine restriction does not have the quantity of data that are available for CR, but reading that book I am quite convinced that CR is nothing less than a Methionine restriction. It makes a lot of example where Methionine restriction could be used to explain some longevity effect like for example the fact the women live longer than men.

If you want to exploit a mechanism to slow down longevity you need to know what is working in that mechanism to optimise it.

Carbohydrate and fat restriction do not case increase in lifespan while proteins and Methionine do!!!

I do not want to convince other people but my advice is to have a good look to this approach and than you make a decision.

This post has been edited by Michael: Jul 19 2009, 11:32 PM

Theoretically, does methionine restriction then require the cessation of supplements such as NAC on account of their structural origins?

This post has been edited by Michael: Jul 19 2009, 11:32 PM

Wouldn't vegans and vegetarians have lifespans similar to what CR people should expect, if methionine restriction is the reason? Or is there significant methionine in non-animal protein?

Another way to examine this theory is to look at the dietary data for specific populations, especially long-lived ones, and compare their methionine intake.

This post has been edited by nameless: Jul 9 2009, 11:44 PM

AFAIK the methionine restriction in rodent studies leads to drastic weight-loss, similarly to CR, which is the reason why it was suggested to be crypto-CR. If there really wasn't enough met in plant products we should see vegans basically "wasting away" (as if they started CR, despite an isocaloric diet). I suppose there's definitely enough met for maintenance in their diet...

This post has been edited by kismet: Jul 10 2009, 12:07 AM

Mat, how did you manage to reduce methionine in your diet? I looked into it briefly but it seems like Met is in everything. At least it's high in some foods that I don't really want to stop eating. Are you sure that you are getting all the amino acids you need, yet restricting Met sufficiently? Does anyone know what the effect of Met restriction is on autophagy?

The body can inter-convert cysteine and methionine but synthesize neither, so the two together are considered a single essential amino acid pair. Any natural source of protein will have plenty of cysteine/methionine. Beans have the lowest cys/met protein percentage of common foodstuffs yet bean protein contains over 70% of the cys/met content of the same amount of meat protein. A low cys/met diet with adequate protein intake would therefore be very difficult to design outside of a lab environment. Certainly NAC (n-acetly-cysteine) supplements would be precluded.

The studies on methionine restriction (Meth-R) have not determined that restriction of other essential amino acids do not produce the same effects.
To quote from one study :



The effect of limiting any essential amino acid in the diet is the same as restricting protein generally. Whenever essential substances are lacking in the cell, the cell consumes some portion of itself (autophagy) to obtain a supply of them. Though the mice or rats in the studies are receiving adequate overall protein, it is likely when amino acid levels are marginal that there are periods of amino-acid starvation (during sleep perhaps) when autophagy would be induced. This autophagy has a side-benefit of possibly clearing the protein aggregates and degraded organelles that the constitutive recycling systems of the cell cannot handle and this may explain the life extension benefits.

grains are high met.
egg whites are high met.
its a met-fest for vegans and vegetarians.

There is no proven method to extend lifespan, not calorie restriction, not anything. The calorie restriction theory may have some merit but the experiments are full of holes.

People need to stop jumping on the latest fad on the life extension bus and just accept that we're all going to get old and die, the end.

So why did you jump on the imminst.org bus?

Taking the easy route and looking at empirical data -

Vegan diets are supposed to be low in methionine, but they don't seem to have longer life expectancy. Anyone have any studies, know more?

Vegan diets are not low met.

The low-methionine content of vegan diets may make methionine restriction feasible as a life extension strategy

Summary
Recent studies confirm that dietary methionine restriction increases both mean and maximal lifespan in rats and mice, achieving “aging retardant” effects very similar to those of caloric restriction, including a suppression of mitochondrial superoxide generation. Although voluntary caloric restriction is never likely to gain much popularity as a pro-longevity strategy for humans, it may be more feasible to achieve moderate methionine restriction, in light of the fact that vegan diets tend to be relatively low in this amino acid. Plant proteins – especially those derived from legumes or nuts – tend to be lower in methionine than animal proteins. Furthermore, the total protein content of vegan diets, as a function of calorie content, tends to be lower than that of omnivore diets, and plant protein has somewhat lower bioavailability than animal protein. Whole-food vegan diets that moderate bean and soy intake, while including ample amounts of fruit and wine or beer, can be quite low in methionine, while supplying abundant nutrition for health (assuming concurrent B12 supplementation). Furthermore, low-fat vegan diets, coupled with exercise training, can be expected to promote longevity by decreasing systemic levels of insulin and free IGF-I; the latter effect would be amplified by methionine restriction – though it is not clear whether IGF-I down-regulation is the sole basis for the impact of low-methionine diets on longevity in rodents.

This post has been edited by okok: Jul 20 2009, 03:37 PM

Vegan diets are not low met, not low enough to show easily measurable benefits at least. Let me explain (or actually, I'll just generously quote M's response). When talking about "low met" in the context of life extension per se (max. life span extension á la CR) and in the context of this thread named "methionine restriction" we are talking very, very low met indeed. This is not just "low" met; it is dangerously low met and cannot be achieved using any normal diet:

Furthermore, any restrictive diet has to be implemented ensuring optimal nutrition (ON). Most standard vegan diets, however, fail to supply many semi-essential nutrients. This problem alone might outweigh all the small benefits of a vegan diet, which is only relatively low in met and only in some cases. Emphasis mine:


Also, notice that perhaps low met is not enough, but it should be also high in Pr (or maybe it shouldn't be depending on what you make of the IGF-1 data), while being low in met to show most benefits. Most vegan diets are rather low in P, though.

Additionally we do not know if there are no risks inherent to real MR in humans:


In short:
Most vegan diets are unhealthy in the first place and this may overshadow any benefits derived from their relatively low met content, assuming they are lower in met to begin with.

This post has been edited by kismet: Jul 20 2009, 05:56 PM

A couple of methionine questions (and please excuse if they are dumb questions, as I haven't studied this issue besides just glancing over posts here):

Has methionine or protein intake been studied in long-lived populations? If so, did any such populations consume a diet that was mostly low protein or low methionine?

Have there been any rodent studies testing other amino-restriction/longevity theories? That is, besides the tryptophan study mentioned here. Perhaps it's not just methionine, but restriction of other amino acids would have the same effect?

Have there been any rodent studies showing excess methionine decreasing lifespan?

And there is also the issue that even if methionine /protein restriction does work in people, that it may not work for humans outside of lab conditions. Immune or health problems from severe restriction perhaps would kill you off before you reached old age.

Lowered methionine ingestion as responsible for the decrease in rodent mitochondrial oxidative stress in protein and dietary restriction possible implications for humans.
López-Torres M, Barja G. Department of Animal Physiology II, Faculty of Biological Sciences, Complutense University, Madrid 28040, Spain.

Available information indicates that long-lived mammals have low rates of reactive oxygen species (ROS) generation and oxidative damage at their mitochondria. On the other hand, many studies have consistently shown that dietary restriction (DR) in rodents also decreases mitochondrial ROS (mtROS) production and oxidative damage to mitochondrial DNA and proteins. It has been observed that protein restriction also decreases mtROS generation and oxidative stress in rat liver, whereas neither carbohydrate nor lipid restriction change these parameters. This is interesting because protein restriction also increases maximum longevity in rodents (although to a lower extent than DR) and is a much more practicable intervention for humans than DR, whereas neither carbohydrate nor lipid restriction seem to change rodent longevity. Moreover, it has been found that isocaloric methionine restriction also decreases mtROS generation and oxidative stress in rodent tissues, and this manipulation also increases maximum longevity in rats and mice. In addition, excessive dietary methionine also increases mtROS generation in rat liver. These studies suggest that the reduced intake of dietary methionine can be responsible for the decrease in mitochondrial ROS generation and the ensuing oxidative damage that occurs during DR, as well as for part of the increase in maximum longevity induced by this dietary manipulation. In addition, the mean intake of proteins (and thus methionine) of Western human populations is much higher than needed. Therefore, decreasing such levels to the recommended ones has a great potential to lower tissue oxidative stress and to increase healthy life span in humans while avoiding the possible undesirable



I'm no expert on this subject either, but I wondered, as mentioned above, on the possible benefits of a vegan diet, and why it doesn't seem to confer any life extension.

1. Has it conclusively been shown that vegan diets are unhealthy? (if not,)
2. Met-reduction being modest in a vegan diet, nevertheless this should show. (also in regard to many advise for a 'soft' met-restr.)

just playing devil's advocate a bit.

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