You Want Fries With That, Um, Thing?

Fast food burgers have very little meat

"The estimated meat content expressed as a percentage of
the surface area on cross section ranged from 2.1% to 14.8%
(median, 12.1%); all but 2 brands showed a meat content
between 10% and 15%. There was no apparent correlation of
meat content and price in hamburgers. The cross-sectional
area of the 5 fields examined microscopically in each
hamburger was 15.7 mm2. The tissue types identified in
each hamburger are summarized in Table 1. In 7 of 8 brands,
more than 20 fragments of skeletal muscle were identified
(Fig. 1A). More than 20 fragments of connective tissue and
more than 20 blood vessels were noted in all hamburgers (Fig.
1B). Other tissue types identified in all hamburgers included
peripheral nerve (Fig. 1C) and adipose tissue (Fig. 1D). Plant
material was noted in 4 hamburgers (Fig. 1E). Rare fragments
of cartilage were seen in 3 hamburgers (Fig. 1F) and bone in 2
hamburgers. Parasitic organisms situated within skeletal
muscle fibers were identified in 2 hamburgers (Fig. 1G). The
parasite was morphologically consistent with Sarcocystis."