what are fastest healtiest ways to burn fat while gaining muscle mass
at the same time? ie burn 12 pounds of fat while gaining 12 pounds of
pure muscle?

The word "healthy" is very subjective, and when it comes to weight
control, "healthy" is just plain controversial.

The most effective way to burn fat from anecdotal evidence is through
a "low-carb" or protein-heavy "Atkins Diet". While many frown on the
thought of eating lots of fat and protein, the enlightening article
"What if It's All Been a Big Fat Lie?" by Gary Taubes (from the July 7
New York Times) will give you a better understanding of the true
nature of the diet. The diet is well known for weight quick weight
loss in a matter of weeks, but has been specifically called
"unhealthy" by many nutritionists. I suggest you read the article to
see how "healthy" the diet is.

You can find the article at 
http://atkinscenter.com/Archive/2002/7/9-672214.html

If you do decide to try this diet, make sure you talk to your doctor
and plan the diet. Weight control is a serious issue and should be
considered carefully.

As for increasing muscle mass, the most effective way is through
bodybuilding/lifting of your major muscle groups. As mentioned below,
increasing body muscle mass is much harder to do "instantly" and there
is no anecdotal evidence to suggest a "magic bullet." Give it some
elbow grease, and you'll do it.

Hopefully I answered your question well. 

Good luck!
 -Ukiguy

Dear fdelt-ga:

I don't mean to sound smarmy. But there is only one way:

Exercise. =) Weight train for the muscles. Aerobic exercise for the weight loss.

Best Regards,
blader-ga

'Fastest' is a difficult stipulation to really advise on.  I can give
some tidbits of advice from the standpoint of a personal trainer that
will work quickly-- but 'fastest' depends on many variables about your
genetics, motivation, age, etc, that I don't have enough details on.
Here is a bit of info:
  There are 3,500 calories in one pound of body fat. An effective
method to lose 12 pounds is to combine a reduced daily caloric intake
with a large increase in large muscle-mass work. To put it another
way, you need to eat fewer calories-- regardless of what foods you got
them from, and do prolonged lifting/movement with big muscle groups.
Areobics is great for large muscle group usage for long periods of
time. If you have a history of difficulty with reducing what you eat--
here is an easy trick that helps a little. Eat the same amount of food
you normally eat during the day, but don't have any of it as a 'meal'.
Meaning eat the same amount, but eat it by snacking constantly through
the day. This is an easy way of tricking your system into not really
ever feeling truly hungry. And, consequently, making it rarer that you
gourge yourself from feeling starved.
 It is far easier to lose 12 pounds than to gain 12 pounds of muscle.
Muscle mass gains are made though the recovery of what is known as
microtrauma. Microtrauma is cellular-level damage made to muscle
tissue when strenuous exercise is performed. Note I said 'strenuous'
and not prolonged. Strength (and therefore mass). Some strength gains
do happen without a gain in muscle mass, for example new muscle fiber
'recruitment', which means your body is learning to fire more muscle
bundles in the muscle group through weightlifting. If you goal is
muscle mass (as opposed to say, having a great curl, or strong
stomach), you need to focus on the big muscle groups. And those are:
Quadraceps, pectoralis major, latissimus dorsi, trapezius, end the
biceps femoris/semitendinosus (back of the upper leg-- opposing group
to the quads). While it's important to work out your other muscle
groups as well-- you will see the largest weight gains in these.
 Also, don't make the mistake of a lot of people getting into lifting
by adiding substantial protein into your diet thinking that will
aid/speed in muscle growth. Eating more than .75 grams of protein per
pound of your body wieght per day is too much. For example if you
weigh 200 pounds, you shouldn't be eating any more than 150 grams of
total protein a day. Any more than that and it's just extra calories
that are also hammering your kidneys as you body get rid of what to
doesn't need for tissue repairs.
One last note on lifting. Many people make the mistake of doing many
sets of a particular movement right after another with just a few
seconds of rest time. While this might be great to impress you
friends, it's not a very effective way to build muscle mass. For any
set after the first for a particular movement-- when you have had less
than 2-3 minutes of rest time, the major reason for not doing as much
/reps/wieght is due to lactic acid building up in muscle the tissue
(as opposed to microtrauma-- which is what you are trying to achieve).
By resting (or doing a differant movement/muscle group) for two-three
minutes, you give you body a chance to metabolize out that lactic
acid, and bring your muscle tissue back up to only the limits that are
imposed by the previous damage/microtrama you did (as opposed to
weakness simply caused by lactic acid).
 Don't forget to rest after lifting for at least two days for a
particular muscle group!!  It's actually the resting in between that
makes you stronger.. not the lifting.. :->

In addition to the other suggestions you might consider the following
elements of a program. These have worked for me.

Drink at least your  8 glasses of water per day. VERY important.

Don't  worry about using scales to determine progress.  I have
recently
lost 3 inches off my waist while GAINING weight due to enhanced muscle
mass as a reslt of a modest weight lifting
campaign.  

Get in a routine of weight lifting and aerobic exercise to insure you
stay
active.  Check out a few local health clubs and inquire about  short
term
membership specials.....many offer a one or two month membership. This
will
allow you to assess the benefits while kick-starting your campaign and
make
the effort more interesting.  I've been to the club 23 days of the
past 36 and
have  "lifted" (or shifted) about  12,000 lbs of weight per visit (I
prefer the
universal machines)  and  have already noticed the  increase in upper
body mass/muscle.  There are 10 stations/pieces of equipment which
seem to cover the entire body.

Make the activities as much fun as possible and don't overdue it.  You
didn't
indicate what  your goal was or how much weight you wish to shed, but
if you only have 12 pounds to lose then shoot for  1.5 to 2 pounds per
week.

Bike riding, walking, swimming, jogging are the common forms of
aerobic exercise and I cycle 3 to 5 times per week (indoor and/or
outdoor).

To avoid  Yo-yo dieting you will have to adapt to a lifestyle that is
practical and comfortable after you have achieved your goal.  Carb
intake has always been my problem, especially late-night eating,  so I
must eliminate them from my diet- especially the  breads and cereal.

Continue your research to gain additional insight regarding the
process.  there are a few books about "The Zone"  which are good
reading and  stress the importance of avoiding foods that spike your
insulin level.....simple starches and sugars.

hm. anyone wants to do research for free? hee. just wondering..who
exactly started this "the body needs 8 glasses of water" theory?
someone locate the source of the above theory. i think the body needs
as much water as possible.

oh. check this out.

http://www.cnn.com/2002/HEALTH/diet.fitness/05/24/cohen.water.otsc/index.html

You may want to look into a ketogenic diet called "BodyOpus"  written
by Dan Duchaine.  It is a very difficult routine to follow, but the
results are fantastic.  In a nutshell, you combine brief periods of
ketosis (5 days) intersperced with "carbing up" cycles of
approxoimately 2 days.  The closer you follow his explicit
recommendations, the better it works.  Obviously the book goes into
much greater detail regarding types of food, meal timing, workouts,
etc.  Warning, he does discuss the use of anabolic steroids as well
(He was refered to as the steroid guru).  You DO NOT need to use
steroids to benefit from the diet / exercise program that he outlines.
 Finally, you should be in "decent" shape before trying this.  It is
not an obesity treatment.  Hope this helps!