Exercise and Caffeine May Activate Metabolic Genes 148
ananyo writes "A trip to the gym could mean not just losing pounds — but also chemical modifications from DNA in the form of methyl groups. The presence (or absence) of methyl groups at certain positions on DNA can affect gene expression. Researchers at the Karolinska Institute in Stockholm looked at the methylation status of genes in small biopsies taken from the thigh muscles of healthy young adults before and after a stint on an exercise bike. They found that, for some genes involved in energy metabolism, the workout demethylated the promoter regions (stretches of DNA that facilitate the transcription of particular genes). Genes unrelated to metabolism remained methylated. Furthermore, similar demethylation could be seen when cultured muscle cells were given a massive (probably lethal) dose of caffeine."
Translation? (Score:5, Insightful)
Re:How can this be possible? (Score:5, Insightful)
Your metabolism helps determine the number of calories you burn. Exercise burns calories directly and also increases your resting metabolism. Weight is still determined by calories in and calories out. As far as I know, there is nothing specific you can eat that is proven to boost your metabolism. While caffeine seems to have an effect on gene expression when taken in near-lethal amounts and injected directly into muscle, it's current use in diet pills is as an upper, diuretic, and appetite suppressant.
None of this violates the laws of thermodynamics. Although, if it did, The Matrix would suddenly make a lot more sense.
Re:Lamark was right after all (Score:4, Insightful)
That would be a stretch. More like he wasn't completely wrong, in that epigenetics and methylation can be passed along to offspring.
Seems to me like "he wasn't completely wrong" is modern biologists bending over backwards for the guy. Epigenetics seems to resemble Lamarckianism only at the most high-level single-sentence overview of "traits acquired in life can be passed on".
Considering how Lamarckianism was supposed to be the primary driver of inherited traits, I'd say it's more like "his flirtations with reality were due to chance alone".
Re:How can this be possible? (Score:4, Insightful)
"Weight is still determined by calories in and calories out."
Not true. Weight is determined by the insulin response triggered by an increase in blood sugar. Calories in/calories out is a good rough guide but Adkins adherents (and the previous low carb diets that have preceded it, starting with the Banting diet [wikipedia.org]) have known for a long time that the endocrine system is the major player in weight gain/loss.
Gary Taubes has done a lot of tremendous writing in covering this topic.
Check this article out if you're interested for more. [nytimes.com]