高齢者の栄養障害の要因の一つに口腔状態や摂食の問題があり､食物摂取に直接影響するのは咀嚼能力の低下である｡咀嚼能力を簡便にかつ客観的に測定するために､咀嚼の進行に伴い色が変わるﾁｭｰｲﾝｶﾞﾑが開発されたが､この色変わりﾁｭｰｲﾝｶﾞﾑ(ｶﾞﾑ)を用いて高齢者の咀嚼能力を測定した報告は未だ少ない｡本研究では高齢者の咀嚼能力の実情を知るため､ｱﾝｹｰﾄ調査とｶﾞﾑを用いた咀嚼能力の測定を行い､食品の咀嚼の難易と咀嚼能力との関連性について検討を行うこととした｡対象者は､活動力の高い在宅の高齢者65名とした｡ｱﾝｹｰﾄは年齢､歯の状態､かみ合わせ評価度､また19食品について摂食可能かを尋ね､普通に食べられる食品の割合を示す咀嚼機能ｽｺｱを集計した｡咀嚼後のｶﾞﾑの色は､色彩色差計にて咀嚼能力の程度を示す a* 値を測定した｡活動力の高い在宅者では､｢義歯群｣が53.8%を占めており､｢欠損歯あり｣はいなかった｡｢義歯群｣間では､かみ合わせ評価度､咀嚼機能ｽｺｱおよび a* 値はいずれも個人差が大きく､顕著な差は認められなかった｡咀嚼の難易の程度が高い食品ほど､かみにくいため義歯依存性はより高くなっており､食べられないと答えた食品の数は､義歯の装着部位が多くなると増える傾向にあった｡As one of the factors of nutritional disorders among the elderly, they have problems in their oral cavity conditions or eating. It is a decreased mastication ability that directly influences on their food intake. Although a chewing gum which changes its color according to the progression of mastication has been developed to briefly and objectively measure the mastication ability, still a few studies has been reported to measure the mastication ability of the elderly using this color-changeable chewing gum. In this study, we planed to measure the mastication ability of the elderly by using a questionnaire survey and the gum to know the actual condition of their mastication ability and then to conduct a study on the relationship between the difficulty of food mastication and the mastication ability. Regarding study subjects, we incorporated 65 elderly subjects who consisted of highly active home inhabitants. In the questionnaire survey, we inquired about their age, teeth conditions, assessment score levels of teeth occlusion,and eating availabilities for 19 kinds of foods and we then aggregated mastication function scores which showed the ratio of the foods that they could ordinarily eat. Regarding the color of the chewing gum after mastication, we measured values of a* which showed the degree of the mastication ability with a color difference meter. Among the highly active home inhabitants,"a group of subjects with some dentures"accounted for 53.8% and a"group of subjects with some lost teeth"in a"group of subjects with only natural teeth"was not present. In the mean while, among the"other groups of subjects with some dentures", no significant difference was noted, because each the assessment score levels of teeth occlusion, the mastication function scores and values of a* had great differences between individuals. When the number of wearing areas of dentures increases, the numbers of foods for which the study subjects answered that they could not eat tended to increase, because a food with a higher difficulty of food mastication required higher degree of dependence on dentures due to more difficult mastication.