I found a couple of interesting links, one is an abstract giving lipid analysis of manure and fish offal fed larvae.

Wiley InterScience: Fish Offal Recycling by the Black Soldier Fly Produces a Foodstuff High in Omega-3 Fatty Acids.(Author abstract) Journal of the World Aquaculture Society. June 2007 v38 i2 p309(5).

The second isn't great news, apparently ingestion of H. Illucens eggs can cause illness. I note that a quick search does not produce other recent corroborating articles, but several old articles are cited, including a USDA article or bulletin. Given the resistance of these larvae to chemical exposure, washing with lava soap or a similar abrasive soap to mechanically destroy eggs or small larvae on one's hands may not be a bad idea.

A case of human enteric myiasis due to larvae of Hennetia illucens (Family: Stratiomyiadae): first report in Malaysia
Malaysian J Path01 1995;17(2): 109-111

4. James MT. The flies that cause myiasis in man. US
Departmment of Agriculture 1947; Publication No
63: 175.

10. Meleney HE, Harwood PD. Human intestinal
myiasis due to the larvae of the Soldier Fly, Hermetia
illucens Linn (Diptera: Stratiomyidae). Am J Trop
Med 1935; 15: 45-9.

11. Harwood RF, James MT. Entomology in human
and animal health. Macmillan Pub CO, 1970: 296-
318.