Talking about different diets in the calorie thread reminded me of this study so I looked it up.
The benefits fo a calorie restricted diet arent new, and it seems that the more simple the organism the more impressive the results are.
But this recent study with monkeys just blew my mind.
Long story short a 30% reduction in calories while maintaining good nutrition roughly extends your life by 20%, reduces the rate by which you age and allows you to live much healthier while alive.
Here's the link to the report, pretty interesting stuff:
http://www.nature.com/ncomms/2014/140401/ncomms4557/full/ncomms4557.html
If I remember correclty my calorie intake should be roughly 2000-2100 calories. Eating the way I do now it shouldnt be hard at all to stick with a healthy diet of about 1500-1700 calories.
FerFAL

Good info, thanks for posting.

It'd be nice if there was a way to see what your calorie intake should be daily for a given body weight and activity level.

Without that I wouldn't know how to calculate a 30% reduction.

Edit to Add: I found an online calculator here: http://www.freedieting.com/tools/calorie_calculator.htm

I don't know what my resting metabolism needs are at this stage in life. I do know most days I eat 3,000+ calories and stand at 5'7" and 140lbs. On days I work out 4-5 days a week, I specifically aim for 4,00 calories.

Going from 3,000 a day down to 2,000 would be rough

IIRC, the benefits from this are see when it is over your lifetime, starting at 50-60 has many benefits, but extension of lifespan is not one of them.

Basically, the studies show an inverse relationship between calories eaten and lifespan (down to the point of starvation).



 

I think the study is pretty conclusive. Pretty much on every living organism tried CR extends lifespan by reducing the ageing process. The less calories you consume the less free radicals you have punching holes through your cells and the slower you age. Of course starving yuorself to death wouldnt be benefical but its clear that a CR diet has benefits.
This is a pretty good link to read more about how it works.
http://genesdev.cshlp.org/content/17/3/313.full
Maybe thats our true natural state, eating little, moving a lot, scrounging calories wherever they may be found.
FerFAL

Yes, but starting when you are 50-60, the extension is trivial.



Think of it this way, the extension is a percentage of life you have ahead--that is time SPENT very thin (which is really what it comes down to).  Let's say you get that 20% boost.



At 10 years old, where you will spend say 70 years under CR, you get a boost of 14 years-- that is actually pretty dramatic.



If you start at 60 with only 20 years to go, you probably not see any real boost at all--the extension is lost in the noise.



The decrease in morbidity still makes it worthwhile, the extension in mortality does not make it worthwhile. It is not that there aren't benefits, just don't expect to add 10 years to your life when you start CR at age 60. If you want the real life extension benefits, you must start early in life and spend your life CR.
 

Does anyone know what the scientific response to this is?

I imagine that part of calorie restriction is also reduced metabolism -- eat less / do less -- but I don't know.

Several possibilities. I don't think anyone has nailed it down yet.



First, adipose tissue is endocrinologically active, so a reduction in fat causes changes which are beneficial.  Therefore, just reducting calories to the point that your fat level stays very low has benefits--so even with a lot of calories, you can get benefit if you burn off more--just keeping fat levels low.



Second, there is evidence that CR modifies the Insulin like growth factor 2 levels, this seems to be a possible candidate for reduction in disease---or at least part of the mechanism.  Whether or not this is reduced when expending a large amount of calories, versus taking in a small amount, I don't know.  Haven't seen that touched on in the studies I have seen.  They all were reducing calories in--versus calories needed compared to expended. They SEEM to indicate that the ILGF2 is depended on calories taken in, not the overall calorie in to out ratio.



I am not an expert in this, but did a far amount of research into it a few years ago--more on CR by periodic fasting that straight CR.
 

True, fasting seems to have several benefits if done responsably.
FerFAL

You could eat different things that are nutritious but not as high in calories I guess...
85 grams of bacon 763 cal 31 g protein
Vs
100 g quinoa           374 cal   13g protein






225 g skyr               120 cal  23g protein






67 g kale                  33 cal      2.9g protein






1 small 95 g orange   45 cal       0.9 protein






28 g granola             132 cal      2.8 g protein






16 g peanut butter      94 cal      4 g protein
753 calories
This is without getting into vitamins, minerals, fiber, digestion, etc.
Say you have 2 or 3 times as many calories to play with.  Scale it up and mix the next two batches of 700 calories.  I know which option I'd take (in a survival situation or in "real life").
Calories measure something but it certainly isn't nutritional quality.  You can eat something with less calories that is WAY better for you and probably more filling.  You'll almost certainly feel better.
 

There was some study that taking glucosamine chondroitan (forgive spelling) triggered the same cellular response as low calorie intake, also I remember another study saying if you got deathly sick you were much better to be a little fat then super skinny.   Skinny people die in the hospitals, a little overweight can shrug off a severe illness and recover.  Do a little googling and I'm sure you can find those studies.

Same for me.

I won the genetic lottery. I eat almost whatever I want. I workout infrequently and I still maintain 5'10 190 of "mostly" muscle. (almost 50 years old)

Screw it, I'll take the bacon.

And the peanut butter.

j/k.  I've been working on diet over the last year because of some heart issues.  I can tell  you first hand that when you eat what they tell you you should eat rather than what you want to eat, you feel a lot better.  I can also say that not eating what you shouldn't can be pretty difficult.  I miss gravy.

I think that's specially true when it comes to kids. When he was younger my oldest son had gastric problems and I remember the nightmare of spending all day trying to feed him a spoonful of food and praying he wouldnt throw it up. He'd lose weight so fast and every ounce of weight he got him to add was a small victory.
With adults I dont think its that much of an issue. I think the benefits of being lean and fit outweight (no pun intended ) the disadvantages.
One of the things I do remember reading was that many of those studies about thin people getting sick more often was that in many cases people do lose weight because they are sick in the first place, and its not that being thin makes them more likely to get sick. Now thinking about it, my sons case is a good example of someone that at the time was thin, yet sick often, but he was clearly loseing weight because of the sickness itself.
FerFAL