Does drinking cold water encourage weight loss?

There should be little controversy about water being a healthy beverage choice, given that the majority of our body is comprised of water and water is calorie-free.  Can it, however, affect our body’ metabolism?  There’s certainly talk about cold water causing a temporary increase in metabolism.  Let’s review some research.

In 2003, Boschmann et al. published a study demonstrating that drinking 500 mL of cold water (22 degrees Celsius) increased metabolism by 30% compared to baseline, while drinking water at 37 degrees Celsius produced a smaller increase in metabolism, as measured by whole-room indirect calorimetry.  This effect was evident within 10 minutes, peaked at 30-40 minutes, and lasted over 1 hour. 

This study, however, was the only one that demonstrated such a positive effect of water on metabolism. 

Then, in 2006, another group of researchers (Brown et al.) challenged this assertion with a study of their own, because other groups had attempted similar studies but were unable to replicate those results, citing that water had no effect on metabolism.  Brown et al. used a more accurate form of indirect calorimetry and used distilled water to eliminate the possibility of an ionic effect on metabolism.  Their study did indeed demonstrate an increase in metabolism after drinking cold water, but it was minimal.  That change was likely due to the energy required by the body to bring that water to its internal temperature.  In general, though, the results of this better-designed, more careful study demonstrated no significant effect of water ingestion on metabolism. 

Is water of any benefit in weight loss?  Absolutely, but probably not because of its effect on metabolism.  More importantly, it provides a sense of fullness, and thirst may be misinterpreted as hunger that really just requires a drink of water rather than a snack.  Don’t stop drinking water, but don’t count on it to be your miracle weight-loss agent.

• Boschmann, et al.  (2003).  ”Water-Induced Thermogenesis.”  Journal of Clinical Endocrinology and Metabolism.  88 (12).
• Brown, et al. (2006).  “Water-Induced Thermogenesis Revisited: The Effects of Osmolality and Water Temperature on Energy Expenditure after Drinking.” Journal of Clinical Endocrinology and Metabolism.  91 (9).

Want to lose weight? Shave your head

I recently (3 days ago) decided to shave my head, as the culmination of my intent to embrace male-pattern baldness.  I knew I would eventually do it, after my widow’s peak gradually became more prominent and then that classic bald spot appeared.  I had been cutting my hair shorter and shorter for the past couple years, then finally decided I’d had enough monkeying around. 

Now, no more haircuts ($ and time), no more shampoo, no more styling products (mousse), no more time spent staring at the mirror before going out to make sure my hair is presentable.  I think the cost of a few extra razors will be minimal compared to what I will be saving in the long run.  But, then I stepped outside into the frigid Minnesota winter air; I had to go get a new hat – one I didn’t mind wearing on a daily basis.

Then, it hit me.  My head was so cold because I was losing heat from my scalp, no longer insulated by hair.  Now my body will need to expend more energy to keep my head warm, and that means I will burn more calories to do so.  It’s a similar phenomenon to the fact that drinking a glass of cold water temporarily increases your metabolism because your body expends energy to maintain its internal temperature. 

I don’t expect a dramatic increase in metabolism from shaving one’s head, but it should have some effect.  Then again, walking one flight of stairs doesn’t exactly drop all your excess weight, but walking an extra flight of stairs, cutting a couple hundred calories, and going for a walk on a daily basis can make a big difference in the long run. 

I’m not aware of any study demonstrating this phenomenon, but will be keeping my eye out for one. 

My suggestion: embrace your male-pattern baldness.  Take it into your own hands and don’t ever think of doing a comb-over or wasting your money on Rogaine/Propecia, etc.