[aethertap]

I read about some research* regarding ego depletion and its relationship to blood glucose levels that was pretty interesting. Basically, they did a study with two groups of people. Both were asked to do some challenging problems requiring concentration, then both were given lemonade. One group's lemonade was sweetened with glucose, and the other with some artificial sweetener. The two groups were then asked to do more challenging problems. I can't recall the actual numbers, but the group that had glucose in their lemonade did significantly better on the second round than the other group, and the two groups were about the same on the first round.

The implication was that the brain uses glucose in its operation, and requires a certain level of glucose to function at full capacity. At least one cause of the brain fog we get after a full day's focused work is that we're low on fuel, which happens to be easy to fix. Unfortunately, it has other effects too that we might not want so much. I've been meaning to experiment on myself a bit with some glucose tabs after a long day of code, but haven't gotten around to it yet.

(*) I think that was in "Thinking, Fast and Slow" but I'm not certain now, too many similar books in between.

[sparkie]

This test is flawed, as it doesn't have a "neutral group" - a group that had neither sugar nor artificial sweetener. How can they conclude that the sugar made people do better, rather than the artificial sweetener making people do worse?

[aethertap]

Agreed, at least from my brief description, which was a summary of a summary out of a book. I'd say it's more likely that it's my own retelling that's flawed, though I haven't read the actual study. They also didn't have a group which was given the same number of calories from a different source (as far as I know) so it's possible that eating a chunk of meat would have the same effect. What I thought was interesting actually was that they were able to demonstrate beneficial effects from intake of calories directly on brain function.

As I wrote that, I did remember a bit of evidence that the glucose was actually beneficial - namely that they measured performance on the problems over time. At the end of the first set, both groups were showing approximately equal degraded performance. Upon resuming on the second set, the group given glucose was back up to nearly the starting level of proficiency, while the group given no glucose was at the same level they stopped at on the first group.

[alwaysinshade]

> I've been meaning to experiment on myself a bit with some glucose tabs after a long day of code

Anecdotal feedback - they work great for short bursts of activity. I use them when playing multiplayer games at night. Given my opponents are usually young and fuelled on caffeinated sodas I need some kind of edge after getting home from work. When I stomp a lobby on team deathmatch it's usually after popping a couple of glucose tabs. A good low-GI meal does much the same, but of course isn’t as convenient.

[hristov]

Glucose is not really an issue. Fructose is the problem. Unfortunately almost all sugar used as a food and drink additive today includes significant amounts of fructose. Glucose is not that sweet by itself so it is rarely used as sweetener in real life.