Drink red wine semi-regularly (a glass or max 2 at a time, not more), but don't abuse. Minimize distilled spirits. Good for relieving stress, but terrible if abused. Beer is not bad, not also not great in large quantities (those carbs are quick to stick into a belly). BE MINDFUL of consumption on a weekly and monthly level. Too much and you get a cloudy head. Too little, and your stress relief is inadequate. Always have wine with food, not by itself. Otherwise, alcoholism may come a-knockin'.
Find your comfort zone (between relaxation and alertness) and make sure not to deviate too much from that comfort zone on any occasion (even bachelor and birthday parties and other occasions with many Russian or other Eastern European or otherwise college-age males).
Don't drink coffee more than once a day (because sensitive to caffeine). Find a good coffee option (a favorite cafe) and stick with it. NEVER drink crappy coffee (aka sock juice). Either get a Nespresso machine if you can afford it (or as a birthday gift ;) or at least find a good coffee place where you can work and have their coffee - once or max, twice daily, not more.
**THE BIGGEST SHORT-TERM RISK FOR BOTH ALCOHOL AND COFFEE CONSUMPTION: DEHYDRATION
Drink at least 5-6 glasses of water a day, preferably 30 minutes before and after meals or snacks. Plan your day accordingly and always be near a safe source of drinking water. It's the simplest, most effective and cheapest cleansing and restorative substance. DRINK WATER RIGHT BEFORE BED AND RIGHT AFTER GETTING UP IN THE MORNING. This helps digestion and toxin removal during the night.
Repeated dehydration is damaging to the organism, as it means accumulates toxins in the body, unoptimal balance of water/sodium, progressive organ damage if left unchecked, etc. The effect of dehydration on the brain range from headache and other hangover symptoms to hormonal disbalance. Effects on the kidneys are more obvious and lasting. JUST MAKE IT A HABIT TO DRINK WATER REGULARLY.
Meta-study of red wine and beer consumption on vascular health (good news on red wine, so-so news on beer): http://circ.ahajournals.org/content/105/24/2836.full
Wikipedia's compilation on this subject: http://en.wikipedia.org/wiki/Health_effects_of_wine#Wine.27s_effect_on_the_body
From Harvard School of Public Health (about alcohol, in general): http://www.hsph.harvard.edu/nutritionsource/alcohol-full-story/
Why do writers drink alcohol: http://www.guardian.co.uk/books/2013/jul/20/why-do-writers-drink-alcohol
Basic coffee health facts: http://www.refinery29.com/2013/07/49833/coffee-health-facts
A fuller list from Wikipedia: http://en.wikipedia.org/wiki/Health_effects_of_coffee
American Heart Association - list of meta-studies on the effects of coffee consumption on heart health (LOTS of good news, for the most part): http://my.americanheart.org/professional/ScienceNews/Health-Effects-of-Coffee-on-Heart-Brain_UCM_443941_Article.jsp
American Institute for Cancer Research - list of ingredients in coffee and the effect of each: http://www.aicr.org/foods-that-fight-cancer/coffee.html
Study on effect of coffee on risk of stroke (weakly good news): http://aje.oxfordjournals.org/content/early/2011/09/13/aje.kwr226.full
Meta-study on coffee consumption and risk of cancers (moderate good news): http://www.biomedcentral.com/1471-2407/11/96