I don't know a whole lot about this, so hopefully someone better informed will chime in. But from what I know about fat storage in human males and females, I would be surprised if the answer didn't have something to do with insulin, testosterone, and estrogen.
- eat grain-free, gluten-free, lowish-carb Paleo (<30-50g carbs from non-starchy vegetables)*
- eat adequate protein from meat and fish
- exercise short (5-15 minutes max) high-intensity 1-3x per week (HIIT, CrossFit, sprint intervals, Tabatas, etc.)
- lift weights (powerlifts or Olympic lifts) 2-3x per week (HEAVY, in the 2-5 rep range for powerlifts and 1-3 rep range for Oly lifts)
- sleep adequately (probably 8-9+ hours daily in a dark room)
- get adequate vitamin D from sunlight, sunlamps, or pills (enough to maintain 50-70 ng/mL)
This will help normalize insulin, which will in turn reduce overall body fat. If you are at 8-10% it is hard for me to see how you will maintain moobs. [EDIT: Actually, due to the role that sex hormones play in determining the location of fat deposits, I suppose it would be possible to maintain some moobs, but they would likely get smaller as you approach 8-10% BF.]
I would also think that these steps will help increase testosterone and decrease excess estrogen. In theory this will help decrease the size of your moobs, as decreased estrogen --> loss of fat in chest region.
To give you better advice, it would be helpful if you give us an indication of
- what your current diet is like (what foods you eat/avoid, rough idea of macronutrient ratios -- does not have to be super precise)
- how long you've been on your current diet
- what your current body fat % is (approximately)
- your age
- your level of physical activity (do you exercise? play sports? lift weights? how often and how hard?)
- how much you sleep on average
*The carb intake recommendation is just a place to start that seems to work for a lot of people. Your individual carb intake may vary depending on your level and type of activity, your age, your body composition, your health/athletic goals, your body's individual tolerance for carbs, other health issues, and other factors.
I'm pretty sure that a lot of this is info you already know, but maybe I hit something you hadn't thought of.
Edit: Dr. Davis just posted his thoughts as well on his blog.