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输入：紫色红薯是近年从日本[](https://zhida.zhihu.com/search?content_id=226105873&content_type=Article&match_order=1&q=%E6%97%A5%E6%9C%AC&zd_token=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJ6aGlkYV9zZXJ2ZXIiLCJleHAiOjE3OTExMzkxNDEsInEiOiLml6XmnKwiLCJ6aGlkYV9zb3VyY2UiOiJlbnRpdHkiLCJjb250ZW50X2lkIjoyMjYxMDU4NzMsImNvbnRlbnRfdHlwZSI6IkFydGljbGUiLCJtYXRjaF9vcmRlciI6MSwiemRfdG9rZW4iOm51bGx9.-32xvuaLamIVhtZxcDg4pWwnBjqrFSTn-_x3IXcorik&zhida_source=entity)引进的新品种红薯，中国农业大学农学与生物技术学院副院长刘庆昌[](https://zhida.zhihu.com/search?content_id=226105873&content_type=Article&match_order=1&q=%E5%88%98%E5%BA%86%E6%98%8C&zd_token=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJ6aGlkYV9zZXJ2ZXIiLCJleHAiOjE3OTExMzkxNDEsInEiOiLliJjluobmmIwiLCJ6aGlkYV9zb3VyY2UiOiJlbnRpdHkiLCJjb250ZW50X2lkIjoyMjYxMDU4NzMsImNvbnRlbnRfdHlwZSI6IkFydGljbGUiLCJtYXRjaF9vcmRlciI6MSwiemRfdG9rZW4iOm51bGx9.ydJi2gCYBnZesDRrNQ_RZgHtG03KbZi7rhBvP-jgtss&zhida_source=entity)指出，紫薯中的花青素[](https://zhida.zhihu.com/search?content_id=226105873&content_type=Article&match_order=1&q=%E8%8A%B1%E9%9D%92%E7%B4%A0&zd_token=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJ6aGlkYV9zZXJ2ZXIiLCJleHAiOjE3OTExMzkxNDEsInEiOiLoirHpnZLntKAiLCJ6aGlkYV9zb3VyY2UiOiJlbnRpdHkiLCJjb250ZW50X2lkIjoyMjYxMDU4NzMsImNvbnRlbnRfdHlwZSI6IkFydGljbGUiLCJtYXRjaF9vcmRlciI6MSwiemRfdG9rZW4iOm51bGx9.A9NiU9LOrtSRTRk9QU9KuEKxeXgFk-zPEMaBGceWJxk&zhida_source=entity)具有显著的抗生物[](https://zhida.zhihu.com/search?content_id=226105873&content_type=Article&match_order=1&q=%E6%8A%97%E7%94%9F%E7%89%A9&zd_token=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJ6aGlkYV9zZXJ2ZXIiLCJleHAiOjE3OTExMzkxNDEsInEiOiLmipfnlJ_niakiLCJ6aGlkYV9zb3VyY2UiOiJlbnRpdHkiLCJjb250ZW50X2lkIjoyMjYxMDU4NzMsImNvbnRlbnRfdHlwZSI6IkFydGljbGUiLCJtYXRjaF9vcmRlciI6MSwiemRfdG9rZW4iOm51bGx9.4qoI7eNOv9Hcu9s09Bthm3fExl2e3FoTa2sVnp8xpmA&zhida_source=entity)氧化作用，在延缓人体衰老方面具有非常好的效果。紫薯中所含赖氨酸[](https://zhida.zhihu.com/search?content_id=226105873&content_type=Article&match_order=1&q=%E8%B5%96%E6%B0%A8%E9%85%B8&zd_token=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpc3MiOiJ6aGlkYV9zZXJ2ZXIiLCJleHAiOjE3OTExMzkxNDEsInEiOiLotZbmsKjphbgiLCJ6aGlkYV9zb3VyY2UiOiJlbnRpdHkiLCJjb250ZW50X2lkIjoyMjYxMDU4NzMsImNvbnRlbnRfdHlwZSI6IkFydGljbGUiLCJtYXRjaF9vcmRlciI6MSwiemRfdG9rZW4iOm51bGx9.tJA7ZRuA34EHtSoYnrKL_oeuz00EmmE2wFVqrS4B3Ak&zhida_source=entity)、铜、锰、钾、锌的含量高于一般红薯5-8倍，尤其是抗癌物质碘、硒的含量比其他红薯高出20倍以上，占食物中的第一位。
输出：紫薯和红薯吃哪个好？