DHADementia⁉Everyday food! Green tea and DHA 認知症⁉日常茶飯事の食！緑茶と

緑茶抽出物と魚油の同時摂取が高齢者の認知機能と 血漿脂質に与える影響

Effects of simultaneous intake of green tea extract and fish oil on cognitive function & plasma lipids in the elderly.

https://www.jstage.jst.go.jp/article/nskkk/62/2/62_88/_pdf/-char/ja

白井展也1, 2*，樋口智之3 ，鈴木平光4 1 独立行政法人農業・食品産業技術総合研究機構 野菜茶業研究所 2 独立行政法人農業・食品産業技術総合研究機構 食品総合研究所 3 くらしき作陽大学食文化学部栄養学科 4 元・女子栄養大学

キーワード : 緑茶抽出物，魚油，脳機能，血漿脂質，高齢者
日本人の食生活の中で，緑茶や魚介類は欠かせない組み 合わせの一つである．緑茶には抗がん作用1），抗酸化効果2） ， 脳機能改善効果1）3）∼5），認知症予防効果6）∼8）などの様々な効 果が報告され，日本人の健康維持に役立っている．一方， 日本は四方を海に囲まれていることから，日本人は魚介類 を日常的に多く摂取してきた．これまでの研究で，魚介類 の摂取は健康に有用で，特に魚介類に含まれる n-3 系高度 不飽和脂肪酸は，中性脂肪低下効果9），脳機能改善効果7）8）な ど様々な効果があることが報告されている．これらのこと から，魚介類と緑茶の摂取は日本人の健康維持と増進に役 立ってきたと考えられる． 近年，高齢者の人口に占める割合が高くなり，高齢化に 伴う疾病が社会に大きな影響を与え，問題となっている． 特に認知症については高齢化に伴い，増加することが予想 されており，増加の抑制が急務である．また，発症したと しても，病状の進行を抑制する事は，罹患者の尊厳を守る だけでなく，介護者など周囲の人の負担軽減に繋がる． これまでの研究から，緑茶に含まれるカテキンと魚油に 含まれるドコサヘキサエン酸（docosahexaenoic acid： DHA）の摂取は，脳機能の改善と維持に効果的であること が報告されている12）∼14）．そこで本研究では，緑茶抽出物と 魚油の長期摂取が認知機能低下の抑制に繋がるのかを明ら かにする事を目的とし，両者の同時摂取が高齢者の知能評 価に与える影響について検討した．Keywords : Green tea extract, fish oil, brain function, plasma lipids, elderly people Green tea and seafood are an essential part of the Japanese diet. Green tea has been reported to have various effects such as anti-cancer1) , antioxidant2) , brain function improvement1)3)∼5) , and dementia prevention6)∼8) , and is useful for maintaining the health of the Japanese people. On the other hand, as Japan is surrounded by the sea on all sides, Japanese people have consumed a lot of fish and shellfish on a daily basis. Previous studies have reported that the consumption of fish and shellfish is beneficial to health, and that the n-3-series highly unsaturated fatty acids contained in fish and shellfish, in particular, have various effects, such as lowering neutral fat9) and improving brain function7),8) . The consumption of seafood and green tea is considered to have played a role in maintaining and improving the health of the Japanese people. In recent years, the proportion of elderly people in the population has been increasing, and diseases associated with the ageing of the population have become a major social problem. Dementia, in particular, is expected to increase as the population ages, and it is an urgent need to control its increase. Even if dementia does occur, controlling the progression of the disease not only protects the dignity of the affected person, but also reduces the burden on caregivers and others around them. Previous studies have reported that the intake of catechins in green tea and docosahexaenoic acid (DHA) in fish oil is effective in improving and maintaining brain function12)-14) . The study aimed to clarify whether the long-term intake of green tea extract and fish oil leads to the suppression of cognitive function decline, and to investigate the effects of the simultaneous intake of both on the intelligence evaluation of elderly people.12 Kita Juzaemon❣ reported that OMGT matcha paste is an easy way to drink highly concentrated catechins and highly nutritious matcha as a part of daily tea consumption. OMGT matcha paste is recommended. It can be recommended to consume fish and matcha paste simultaneously as a way of eating easily oxidised fish oil without oxidising it.

12代喜多重左衛門は、日常茶飯事に高濃度カテキンや、栄養価の高い抹茶成分を簡単に飲む方法として、OMGT抹茶ペーストを推奨します。それは、酸化しやすい魚油を酸化させないで食す方法として、魚と抹茶ペースとの同時摂取を推奨できます。The 12th generation Kita Juzaemon❣ recommends OMGT matcha paste as an easy way to drink highly concentrated catechins and nutritious matcha components on a daily basis. It can be recommended to consume fish and matcha paste simultaneously as a way of eating easily oxidised fish oil without oxidising it.

抹茶ペーストで作った抹茶ドリンクはいかがですか❣

高度不飽和脂肪酸を含む魚油は酸化されやすく，魚 臭などの不快臭を発することがある．緑茶抽出物には，脂 質の酸化を抑える効果が知られており ，両者の組み合わせ は，生理機能の向上だけでなく，食品の品質向上にも利用 できる．本研究の結果は，これらの食品の利用に役立つと 考えられた．
Fish oil containing highly unsaturated fatty acids is easily oxidised and may emit unpleasant odours such as fish odour. Green tea extract is known to suppress fat oxidation, and the combination of the two can be used not only to improve physiological functions but also to improve food quality. The results of this study could be useful for the use of these foods.

 要 約

緑茶抽出物と魚油の 6ヶ月間の同時摂取が，高齢者の認知機能と血漿脂質に与える影響について実験した．緑茶抽 出物と魚油の同時摂取は，摂取前に比べて，6 か月後の知 能評価スケールを有意に改善した．また，緑茶抽出物と魚 油摂取群の6か月後の知能評価スケールの増加は，プラセ ボ群に比較して，有意に高かった．これらの事から，緑茶 抽出物と魚油の同時摂取は，高齢者の認知機能を改善して いる可能性が示唆された． 血漿中の DHA および EPA の割合は，両群とも摂取前 に比べて 6ヶ月目で高くなった．しかし，3ヶ月目におい て，緑茶抽出物および魚油摂取群の DHA および EPA の 割合は，プラセボ群に比べて，有意に増加を示した．これ らの変化は，途中，試験群による違いが見られるものの， 最終的に食材に提供される魚介類の増加が影響したと考え られた． 血漿中の中性脂肪含量は，緑茶抽出物および魚油摂取群 において，摂取前に比べて，6ヶ月目に有意な低下が示され， 高齢者においても，緑茶抽出物および魚油同時摂取は中性 脂肪の低下に有効である可能性が示唆された． これらの事から，緑茶抽出物と魚油の同時摂取は認知機 能の改善に有効である可能性が示唆され，また，高齢者に おいても中性脂肪の低下に有効であると考えられた． この研究は，農林水産省委託プロジェクト（平成 16 年 ∼18 年）により行った
Summary.

The effects of simultaneous intake of green tea extract and fish oil for 6 months on cognitive function and plasma lipids in elderly people were tested. The intake of green tea extract and fish oil significantly improved the intelligence rating scale after 6 months compared with the intake before the supplementation. The increase in intelligence rating scale after 6 months was significantly higher in the green tea extract and fish oil intake group than in the placebo group. These findings suggest that simultaneous intake of green tea extract and fish oil may improve cognitive function in the elderly. The percentage of DHA and EPA in the plasma of both groups was higher at 6 months than before intake. However, at 3 months, the percentage of DHA and EPA in the green tea extract and fish oil intake groups increased significantly compared to the placebo group. These changes were considered to be influenced by the increase in the amount of fish and shellfish ultimately provided in the diet, although there were some differences between the study groups during the course of the study. The plasma triglyceride content was significantly lower in the green tea extract and fish oil intake groups at 6 months than before intake, suggesting that simultaneous intake of green tea extract and fish oil may be effective in lowering triglyceride levels even in the elderly. These findings suggest that simultaneous intake of green tea extract and fish oil may be effective in improving cognitive function and lowering triglycerides in the elderly. This study was conducted under a project commissioned by the Ministry of Agriculture, Forestry and Fisheries (2004-2006).