I'd like to point out a little something about health and poker play as well. If you look at any of the interviews or studies done on the highly successful poker players, the majority of them are very fit and they exercise regularly. I don't find this to be a coincidental correlation. Exercise and healthy eating increase blood flow, brain function, and stamina. Brain function is the key to good poker play and if you are at "max thinking ability" you will be at your max poker playing level. If you are a live player, physical health and blood flow could be the difference between wearing your stressors like an article of clothing or sitting like a statue. Stamina is what will allow you to keep all of this together after a 24 hour session when that group of guppies sits at your table and doesn't want to stop giving you money. All of these are very important aspects of winning that correlate directly to your physical health. There's a reason most of the people you seem to run into at main event final tables are physically fit (and I say most since the occasional unfit person does make it through).
On a second note, I'd like to factor in something that wasn't pointed out here. Drug and alcohol abuse. These are a very large factor when it comes to poker because along with that DG gene, comes the drug and alcohol abuse gene (most people who hold the gene to become addicted to one thing, can easily become addicted to all things). Many poker players, and my favorite of all time being one of them (Stu Ungar), were once or still are addicted to one substance or another. Any substance used prior to play will skew these health variables as well because a person cannot be at max mental capability when under the influence of a mind altering substance. Don't get me wrong, I enjoy the occasional drink or smoking a little bud every now and then, but combining that with poker player is just asking for a loss. So keep the substances for fun times and your poker time separate.
I think that a lot of players have the same problem
