There is quite a lot of science and study behind fasting, and it can actually be good for your health. I say this as someone who does a caloric fast (read: no caloric intake at all, fluids allowed) 6-7 times a week for intervals of 16-20 hours, in addition to my 3x weekly heavy weightlifting programme and my full-time job as a programmer/devops.
As of right now I'm the healthiest I've ever been in my life (physical strength and cardiovascular health), and my mind is as sharp as ever, especially when I'm fasting.
biohacker Dave Asprey publishes had developed "The Bulletproof diet" around these principals (and a lot of others). He's selling stuff, but also gives a ton of advice for free. Google it if you are interested.
Sure. It's incredibly simple, even if there are a lot of concepts to grasp.
Diet:
The macro-nutrient decomposition I tend to follow can be calculated for your bodyweight, height and level of physical activity here: http://www.1percentedge.com/ifcalc/ . Note that your level of physical activity is most likely sedentary, even if you plan on exercising. The higher levels are for people who have physically demanding day jobs. The rest/workout split toggle in the top left of the "Macro Calculator" tab will give you different total caloric requirements based on if you want to gain/lose/maintain weight. Remember: a ~500kcal/day deficit from your TDEE (total daily energy expenditure) translates to losing 1 lb/week, and vice versa for a caloric surplus. You can play around with the 4th tab to see what goes on.
The tl;dr version of this calculator is basically: eat more carbohydrates on workout days, and eat more fats on rest days. Eat 1g of protein per lb of body-mass on all days, and try to hit your daily caloric goals on all days.
Meal Timing:
Here's a typical day for me:
* 6:30am. Wake up. Do morning things.
* 7:15am. Take 10g of BCAAs with water, 4000IU of Vitamin D, and 10ml of concentrated (high levels of EPA/DHA) fish oil.
* 7:30am. Take public transport to gym.
* 8:00am. Double-shot of espresso. Sometimes I skip this - I purposely cycle on/off of caffeine every few weeks.
* 8:15am. Start exercise routine. Lift heavy things. Lasts about an hour.
* 9:15am. Finish workout. Ingest 10g of BCAAs.
* 9:30am to 2:00pm. Work.
* 2:00pm. First meal of the day. No significant calories (< 50kcal) before this.
* 6:00pm. Second meal of the day.
* 9:00pm. End of caloric intake window.
* 11:00pm. Bed time.
For rest days, I skip the BCAAs and the gym (obviously).
Of course the above isn't written in stone, and sometimes I break my own rules by going out with friends, having a drink or two past 9pm, and so on. But you get the general idea.
Exercise:
Lift heavy things, and perform compound movements. My exercise regime consists of heavy squats, bench press, standing overhead press, Pendlay rows and deadlifts. Any other exercises are incidental, and I try to avoid muscle-isolating exercises in general.
I would highly recommend reading Starting Strength by Mark Rippetoe (even though some disagree on his precise methodologies, it's still the best introductory book out there), and perusing the http://stronglifts.com site as well. Once you've gotten past the point where those programmes are effective (which will take months, if not a year), there are many intermediate to advanced compound-lift based programmes that you can switch over to.
Sorry for the long post. I could go on for ages about this stuff; it's incredibly interesting, and is actually quite formulaic. If you eat what you're supposed to eat and do the exercises you're supposed to do, your desired results just... happen. Makes the scientist in me very happy ;-).
Indeed – I try to avoid the hive mind (when it isn't backed by science) and form my own opinions, though. The great thing about personal fitness and nutrition is that everyone has got a great laboratory at their disposal at all times.
As of right now I'm the healthiest I've ever been in my life (physical strength and cardiovascular health), and my mind is as sharp as ever, especially when I'm fasting.