"They
produced transgenic mice in which expression of the UCP-2 gene (closely
related to UCP-1) is placed under the control of the promoter for
hypocretins (also called orexins). Hypocretins are peptides that are
produced only by cells in the lateral hypothalamus (3). By placing UCP-2
expression under the control of this promoter, the investigators effectively
placed a small heater into the hypothalamus. As their data show, this caused
heating of the preoptic area, a region in which previous work had shown that
insertion of heat probes would cause a reduction in body temperature. The
result is that the transgenic animals expressing the UCP-2 gene had a
continuous reduction in body temperature by 0.3° to 0.5°C."


It will be interesting to see how low they can get the temperature and seeing if it produces longer lived rodents. I forgot to state that these rodents were nowhere near as long lvied as CR'd mice... decreasing their temperature only allowed them to reach quite old age, but not crazy ages like human equivalent of 170~ years as lifelong CR does.

Lowering temperature like this in mice increased their lifepan, and would be equivalent of around 8 years extra for humans...

Good example of how a theory does not always work as predicted in practice. When human core temperature drops to 27 C (actually, long before that point), our metabolic processes don't just go twice as slow, they stop completely and we die.

I failed to mention that was in vitro Lisa. But since you volunteered, how low can we go and stay alive? I know they cool some surgery patients way down for short periods.

They do, but they are on a heart bypass machine that keeps them alive. Usually at core temps below 90 F (32.2 C), cellular metabolic processes shut down, major organs fail and clinical death ensues. Core body temp of 95 F would be considered mild hypothermia for most.
Now, I know that brain death can take a bit longer to occur at those lower temperatures which is how some cold water drowning victims can be revived after being submerged for up to an hour (note that this does not always work...it's a crap shoot whether or not the victim doesn't have severe brain damage the longer they're under), but it does occur and after a period of time, there is a point of no return where revival is impossible.

AFAIK, below about 80F, the risk of v-fib becomes very high and is very difficult to convert using standard ALS protocols. OTOH I believe the people have been revived from very severe hypothermia/cardiac arrest with no apparent brain damage due the "mammalian diving reflex". This would be in hospital tho with external blood re-warmers and external cardio-pulmonary support.

Human temperature variation effects
http://en.wikipedia.org/wiki/Body_temperature

Its good to see that temperature probably contributes to the life extension effects of CR. CR is quite complex and it seems like there are several factors contributing to extreme longevity.

Last night I increased my over night fasting time last night, I woke up about 30 minutes ago with a body temperature of 34.85 degrees celsius (94.73 degrees Fahrenheit). Cold eh?

I'm not sure which is more worrisome; the fact that you seem to see mild hypothermia as a good thing or the fact that your body doesn't seem capable of recognizing that it's too cold.

Well it was probably more like 35.2 because the temp I took was oral temp. Soon as I got out of bed and started to move around, eat, it went up a bit

1. I woke up alive
2. I woke up feeling fine (apart from a bit cold on the feet)
4. My temp has been very low for the last 2 years
3. Lower temperature (within the species) = longer life

CR can lower Temperature by upto 2 degrees celsius in rodents, and thats exactly what I wanted and got too

What is to worry about anyway? I know the consequences of hypothermia, and I don't intend to let it drop any further than that.

I'm happy to hear that you woke up alive. It can really tend to ruin your day when you wake up dead.

I'm not worried if you aren't but if your body can't recognize when it's hypothermic and respond correctly, you could wind up in serious trouble before you realize that you are in trouble should you get into a situation where you could become even more hypothermic. Good thing Holland generally has mild winters. You'd really be in trouble where I live.
A two degree drop in body temperature would bring you to 96.6; not 94.73 or were you talking about trying to achieve a body temp 2 degrees below the lower end of the range of normal?

2 degrees celsius I meant... but its probably a bit less than that because temperature is generally lower as soon as you wake up in the morning without moving. So my temperature is usually roughly around 1.5 degrees celsius lower than normal waking time temperature.

My father is 52 though and has the same body temperature as me in the mornings for a long time now (the same for most of that side of my family). They all look around 10-15 years younge too, so it hasn't harmed them at all. Plus they all seem to have the similar health biomarkers as me even though they are not donig CR

Everybody- not sure if this was already posted in this or a related thread, but the red wine but also calorie restriction effect on genes received some very interesting coverage by two scientists on Charlie Rose the other night... you can see the whole show on google video (for 99 cents for the full show) under the 'Red Wine and Mice' topic- here is the link...

http://video.google.com/videosearch...arlie_Rose&so=1