I generally support working out fasted and eating carbs after your workout, when your muscles are very insulin-sensitive and will suck them right up.  Also, eating them pre-WO just sticks you in glycolysis, and you'd probably rather encourage some degree of FAO.  "Train in the energy system you want to use" is a solid maxim.

JS

Another thing I've noticed is that when I get up early enough to go to the morning class (I'll do that one fasted) that I crave fat or fatty cuts of meat afterwards and very little carbs.  Anyone else had this experience? 

Jen

Digestion requires energy...so if your body is efficient at using stored energy, you'll get more done in a fasted state. 

And I suspect that eating a carb surplus throws your body into a sugar-demanding mode (i.e. you lose some of your metabolic flexibility), which will result in the "hazy" (hypoglycemic) feeling you describe when you try to fast.

Glad to help!

JS

There are exceptions. I feel great, almost high, after a really good prime rib. Also, I can't fast at all if I haven't been consistent with low-carb paleo. If I'm eating any significant carbs, even fruit, fasting doesn't produce these good effects; instead, I get hazy, unable to think, and feel "odd." By odd, I mean as if I'm going to die. But 3 days of perfect eating lets me again fast easily.

It's definitely why fasting is a high...and I suspect you're right, that it also contributes to the early stage vegan high.

I too have found that eating meat, eggs, and veggies (i.e. no starch) when hungry often leaves me quite buzzed.  It's only once I start piling on the starch (or consuming heroic amounts of meat) that I get the post-prandial blahs.

JS

And...I've been Intermittent Fasting for a couple of months. Usually 19 hour fast, and a five hour eating window. I've definitely had days where I've ridden that knife-edge of hunger and it's been great for creativity. Yesterday, however, I became ravenous after about 15 hours. One of those, 'If I don't eat something, I'm gonna kill something' hungers. So I ate. Not wanting to break from work, I ate while I worked.

Whoah. It was like the calories were being fed straight into my brain. It was a high. Fatty ground beef and scrambled eggs, and I felt like I was trippin' balls. Grehlins rock, but feeding the beast (when it's REALLY hungry) is pretty awesome too. I can't remember the last time food had that effect on me.

Crap. When I started typing I swear I had a point.

I wouldn't worry about it.  As my latest article states, Parmesan is a massive source of umami.  And "shaving bits onto broccoli" is a lot different than making a big cheese quesadilla (I think I lived mostly on these when I was vegetarian) or binging on Kraft Singles.

I'm not strongly anti-dairy anyway: Eat Like A Predator summarizes my stance on the matter.  Butterfat is fine, and cheese in condiment quantities isn't a big deal unless you're intolerant.

JS

Congratulations on great progress!

JS

However, I don't want to stop.  Went totally paleo diet on January 16, 2012.  I will still have the occasional full-fat yogurt mixed with my local honey, and still use cheeses in small amounts.  30lbs and 6 inches from my waist later, I feel awesome.  Part of this change is that in this process, I found I just wasn't hungry as much, and started with IF about a month ago.  Typically, from 9 at night till about 1 in the afternoon, I don't eat.  Not surprisingly, I get more work done in that 4 hours right before my afternoon feeding.  Ghrelin Addict?  Nah.  I just enjoy it a bit every day. 

But, I can quit whenever I want.

Brynn:

But it's open late, and so convenient!

That's why I almost always cook roasts instead of individual meat portions: so I've got pre-cooked real food available quickly if I need it.  Tri-tip, bacon, or prime rib > anything on the Taco Bell menu.

Furthermore, the longer you eat like a predator, the less you'll be tempted, because you'll get "the munchies" less and less often.  For a healthy human, hunger is a signal, not an alarm.

JS