Simple theoretical equations were proposed for water ¹H T ₂ ( T _2obs,W) observed in wide-line NMR experiments with three cases of food gels in which polysaccharides or protein polymers have the conformations of random coils or ordered structures (case A), both random coils and ordered structures (case B), or random coils, ordered structures and aggregated structures (case C). On the basis of the equations, the temperature dependencies of T _2obs,W were calculated for solutions with polymers in random coils and ordered structures. The steep change of T _2obs,W around the conformational transition temperature, which is frequently seen for food gels, was reproduced by changing the ratio of polymers with the random coils and ordered structures. The formation of aggregated structures was also described. Experimental results of T _2obs,W for a gelatin solution and carrageenan solutions were demonstrated and compared with the theoretical values given by the equations. The temperature dependencies of the T _2obs,W values were well related with the conformational changes of the polymers in those solutions.