Does Metabolism Drop During the Winter??

[BamaDave]

Just wondering. I have noted that I seem to be requiring fewer calories during the last month or so. In fact, I have unexpectedly added 2-3 pounds during November, when I have generally been eating fewer calories than during a failed bulking attempt during late Summer. Of course, Nov. included Thanksgiving and a couple of other food fests, but I wasn't so off-the-track that a weight gain should have been triggered. The only other variation is that I have been increasing my running mileage lately, esp. Sunday long runs, since I am training for a Feb. marathon. Stress hormones slowing metabolism??

Just wondering whether others experience a drop in metabolism this time of the year. I know it's hard to gauge with all of the holiday parties, big dinners, etc.

[DKing]

You know, I have no idea what the answer to this is but its a really interesting topic. I can see why we would have some sort of built in survival instict to slow the metabolism down when it gets cold because not as much food would be available. I wonder is Dr. Johnka has read anything about this?

Danny

[mcl]

I don't really know but it would make sense to me that if anything your metabolism should increase in the winter. Especially if you spend time outdoors because for your body to maintain its temperature you should have to burn more calories.

[OldGuy]

Found this. Don't know if it answers the questions completely, but it's a start.

http://www.thefactsaboutfitness.com/news/cold.htm

[mcl]

I stole this exerp from here
article

Some experts postulate the existence of a so-called "thrifty" gene, which regulates hormonal fluctuations to accommodate seasonal changes. Theoretically, it works in the following manner:

* In certain nomadic populations, hormones are released during seasons when food supplies have traditionally been low, which results in resistance to insulin and efficiently increased fat storage.
* The process is reversed in seasons when food is readily available.
* Because modern industrialization has made high-carbohydrate and fatty foods available all year long, the gene no longer serves a useful function and is now harmful because fat, originally stored for famine situations, is not used up.

Such a theory could explain the high incidence of type 2 diabetes and obesity found in Pima tribes and other Native American tribes with nomadic histories and Western dietary habits. The traditional low-fat high-fiber foods (corn, lima beans, white and yellow teparies, mesquite, and acorns) of the Pima people may have protected this genetically susceptible population in the past from the high incidence of obesity and type 2 diabetes they are experiencing now.

[Lost Dog]

I think a book about this subject would be fascinating.

I've always been fascinated at how different ethnic types and cultures can eat and live so differently and yet be trim and healthy until something comes along and changes things. It would be sort of a history of the whole world and the how the different diets and exercise habits worked for them then and are either working for or agains them now.

Too many diets recommend eating like "these people" without taking into account the possible genetic factors.

There's not really a clear group of people who's eating habits we should ALL mimic, although it's pretty clear who's eating habits we shouldn't mimic: the typical American's.

For me, I find that eating as close as possible to the way that prehistoric man may have eaten is working out okay. I can't really argue with the logic behind this type of diet plan. Although, my own lineage may have adapted to the grains, etc. that my German ancestors started to eat, that doesn't mean that they did better when eating that way. They may have just done okay despite the bread.

[BamaDave]

Yeah, I was wondering whether ethnic heritage would contribute to this. People who lived in tropical areas would not have needed a Winter slowdown on metabolism. My ethnic heritage is predominantly Irish, German, and Swedish (with a dash of Dutch and Scottish and an unknown amt of Cherokee -- could be as high as 1/4 or 1/8), so my ancestors were dealing with cold Winters.

[Mahler]

Dave,
I have noticed the same thing. I seem to require fewer calories even though I have not changed the intensity and frequency of my workouts. If anything they have increased. I find this to be fascinating.

Mahler

[RipStone]

There is a thread about this on T-mag right now....

http://www.t-nation.com/readTopic.do...itan?id=528934

I think cus we are animals that our bodies naturally want to store more fat when it gets cold outside.

[Newlife]

Wonderful info. I spend a lot on time on the mountain during winter and find my BF% drops. The only difference is I am snowboarding and snowshoeing backcountry vs. riding a Mt. Bike and doing long walks and hikes. I assume I burn more calories during the winter due to the cold, but never had science to back it up. Assuming our cardio and lifting are the same, would you burn more cals in the winter due to the cold?

off to T-rag to see

[Milko Georgiev]

During the winter body stores more fat.
One or two percents up.