Well, I can not comment to much on the US military.

I have only eaten the food provided in camp Grayling, Michigan. I will tell you that being in the reserves in Canada. I no longer eat military food, there is so much crap that I just feel like shit eating it.

I bring my own, if I am only going for a weekend I'll bring steaks, if longer homemade jerky+ dried fruit and so on, with nuts etc.

The US food on bases (well a base) i've seen is mostly all processed I think it would be next to impossible to go VLC on the food they are giving you unless you have some kind of specific menu you get to select from.

Coconut cream (I have one that comes in a box) 99 cents for 1000 calories of fat. Would be a good start, not sure of the non refrigerated self life however.

I am in Japan and unfortunately for most U.S bases abroad they seem to still think that the Golden Arches provide the necessary nutrition service members are looking for. As for the Commissary, requesting Grass Fed beef and coconut milk is impossible. Not sure about the dinning facilities for the single individuals but from what I have heard, crap food, carbo based as usual and soda based drinks. It seems that trying to ask for healthy food is impossible for anyone to agree on but when they do they offer grains and other bullshit that doesn't account to even come close to being Paleo.

I can't say anything about Army OCS, but I know you have to be pretty diligent at military dining facilities, and be willing to splurge out of necessity. Food is cooked to provide the most food for the most people, so expect tons of fried and starchy foods, and commercial salad dressings. There will always be a salad bar if the main dish looks like it was scraped off the drill sergeant's boot. There is supposed to be two options, and sometimes the option is a fish dish or chicken. The option is usually the one none of the other guys and gals are taking, so you can have extras. Load up on the fish dishes and vegetables if you can, and eat a salad at every meal. Don't be afraid of the rice or a potato here and there if you are doing a lot of demanding training.

When you get out of training, the commissary is a great place to get what need. The Organic sections are growing, and inexpensive. You can find a lot of foreign vegetables not found in most chain supermarkets. Unfortunately, grass fed beef won't be much of an an option there, but the meat is very affordable and seafood isn't bad. Most places have their own butchers so you can ask for special cuts or soup bones and offal. Sometimes you can find cuts of offal in the case pre-cut. I shop there as much as I can, and it has saved my little family from living in a cardboard box. The savings will spoil you.

Best of luck! There won't be a shortage of "food" in the military, you just have to be more selective than most, and willing to sacrifice. The quality will not be held to your personal standard, but if you need to eat pick the best option.

I am active duty military and paleo, and while difficult at times, it can be done. Every meal offers some acceptable choices and if all else fails, there is always a salad bar at lunch and dinner.

The hard part is being out in the field and onmy having MRE's to eat. Then you have to make sacrifices(go hungry or eat the junk) or try to plan as far ahead as possible and bring your own snacks if allowed.

Inform them of your special dietary concerns and if you must, let them know you'll be happy to help defray some costs of your bacon, eggs, butter and steak diet.

It's basically a no carb diet and they should not give you too much flak about it especially if you're on good terms with the cookhouse.

Bringing your own paleo-friendly snacks as suggested by Ryan H is a good idea too.