You might get better suggestions on the Fruit forum.

I have little to no personal experience with growing or eating most of these, but here are some plants to look at:

Arbutus unedo. 'Compacta' gets to about 6' but the straight species is taller. Edible(?) fruit.

Mahonia spp While the most common garden type I've seen is low-growing, there are others, perhaps less commonly found in commerce, that grow much taller. Edible fruit

Clumping bamboo - Bamboos come in a range of sizes and hardiness, so you can most likely find one that works, but be sure to look only at clumping, not running bamboos which are difficult to contain. Edible shoots

Many common needled evergreens can be used to make teas: spruce/Picea, hemlock/Tsuga, fir/Abies, and pine/Pinus. They are nutrient rich and so make sense as a survival food, but I honestly can't say that I've felt any inclination to try them.

You might want to add information on where you are since 7b in the southeast US is quite different than 7b in the southwest US. For example, the taller Mahonia I've seen were growing in Utah, and I know that at one point at least one was offered by a New Mexico nursery, but I don't know if it would be happy in the SE US. Other growing info would be useful as well; is this for sun or shade or part sun? Are you willing to prune on a regular basis? Do you want evergreen for privacy or the winter green color? If for privacy, there are some densely twiggy deciduous large shrubs/small trees that might work for you such as hazel (edible nuts if you can beat the rodents to them) though they will need pruning.

You could also ask on the shrub forum. This forum deals more with design, not specific plants.