[codewright]

"Turbo shots" or "red eyes" in your coffee are a placebo btw. Espresso has a lower concentration of caffeine than standard drip. So by putting a "turbo shot" in your cup, you're actually lowering the caffeine concentration.

Wants to be hyper-rational and metric-aware about his sleep but didn't know anything about caffeine?

Okay.

[pranjalv123]

I don't think that's true. A 16 oz Starbucks coffee has 330mg, while a 2oz Starbucks espresso has 150mg. So the espresso has 4x as much caffeine per ounce.

(http://www.cspinet.org/new/cafchart.htm)

[guizzy]

Espresso has a lower volume of caffeine, but it definitely has a higher concentration.

http://www.mayoclinic.com/print/caffeine/AN01211/METHOD=prin...

Espresso, restaurant-style 1 oz. (30 mL) 40-75 mg

Generic brewed 8 oz. (240 mL) 95-200 mg

The brewed coffee thus has between 11.9 mg and 25 mg of caffeine per oz.

If you added a shot of espresso (let's assume the weakest one at 40 mg of caffeine) to an 8 oz of very strong coffee (at 200 mg of caffeine), you'd still be increasing the concentration to ~26.7 mg/oz.

And that's stretching the limits of these calculations; a 200 mg 8 oz coffee is crazy strong, amounting to two and a half cans of Red Bull.

[wonnage]

Espresso has a higher concentration of caffeine. Most espresso drinks are mixed with a ton of milk, so lattes, etc. do end up being less concentrated than drip. But dropping a shot of espresso in your coffee will up the caffeine concentration slightly.

[gerjomarty]

I hear a lot about cutting caffeine after 3pm to have it not affect your sleep, but I generally assume people are talking about coffee when they mention this time. I care more about when I should stop drinking tea, which apparently contains less caffeine.

Can I just halve the time required if tea has half the caffeine (let's say)?

[nateweiss]

There are some pretty good decaf black teas (not herbal) which are reasonably satisfying if you want to have a cuppa later in the day.

If you're in the US, the Stash decaf range is IMO the best of the common supermarket brands (the normal American teas like Lipton and Tetley are pretty terrible in their decaf versions). If there's a gourmet store around, they may have the English brands such as Typhoo or PG Tips in decaf, which are pretty great. If you're in the UK then any advice on tea from the likes of me should just be ignored out of hand... :)

[octotoad]

I'm not a coffee/tea drinker and I don't drink soft drinks (caffeine or otherwise) apart from when its mixed with alcohol. I personally find it takes me a lot longer to get to sleep after having consumed pre-mixed alcohol involving things like cola. Beer, on the other hand, does not seem to have the same effect even when consumed at the same time of day.

[burriko]

Last year I made the decision to switch to drinking only decaf tea after 3pm, and since then I've found that I have much less trouble getting to sleep. Purely anecdotal of course, but I highly recommend it. Initially I was worried about the taste, but there's honestly not a huge difference.

[fyi80]

Can you pick a decaf herbal tea for afternoon drinks?

[yor]

I think you're thinking of the difference between robusta and arabica beans. Arabica has less caffeine than robusta, and -- at least in America -- more espresso roasts are arabica.