A hypothesis is proposed where the main low-energy nuclear reactions in glow discharge experiments involve three-body recombination between a deuteron and the nuclei of a D2 molecule trapped in a dense lattice of a chemical compound of transition metal and impurity. Two D's fuse to 4He, and the energy is "converted" by expulsion of the third deuteron. Three boson (efimov) interactions can have a longer range than two boson interactions. The scheme accounts for the low reproducibility and short duration of the effect because of rapid destruction of the active structure by sputtering, radiation damage, bubble formation, or chemical changes, and it conforms to the reported prevalence of 4He >> tritium >> neutrons.