堅果/全穀類取代紅肉的好處
肉類雖然是大多數食物中蛋白質、飽和脂肪酸和鐵的主要來源。不過,現在拜醫學研究之賜,讓我們了解肉類雖然有豐富的營養,可是也含有有害健康的成份。例如,肉類所含的左旋肉鹼和膽固醇是導致動脈粥樣硬化的禍首,肉類的血紅素鐵也是種強烈親氧化劑的致癌物!
再者,哈佛大學研究顯示,如果從嗜吃加工紅肉改為每天吃一份堅果來取代各種紅肉的話,可以降低39%的早逝和53%的第二型糖尿病之風險。同樣地,完全不吃紅肉改以每天吃一份「全穀類」(32克一片全麥麵包或200克一杯煮熟的糙米飯或麥片)來取代,也能降低34%的早逝和55%的第二型糖尿病。
營養、有效又無害的補血良方
雖然,肉類血紅素鐵的吸收要比植物鐵質的吸收高,但是高的吸收率卻伴隨著增加癌症、心血管疾病、糖尿病和早逝的危險,這並不符合選擇食物「營養又無害」的原則!那我們應該如何補充安全的鐵質呢﹖
健康地補充鐵質,就是從新鮮的蔬菜水果中直接攝取到足夠的鐵質,這是種既營養有效又無害的吃法。富含鐵質的蔬果有花椰菜,豆類(豌豆、紅豆、黃豆、黑豆),深綠色葉菜(菠菜、紅鳳菜、紅莧菜、甜菜根),全榖類(糙米、全麥食物),葡萄(葡萄乾),西瓜,紫菜,堅果類等。蔬食者食用含有高含量Vitamin C的蔬菜和水果,可以增加加鐵吸收。研究指出缺鐵性貧血的罹患率,肉食者和蔬食者是沒有差別的。補血最健康的吃法是多吃富含鐵質和維生素C的當季節的蔬果!如果還擔心鐵質不足,每天也可以補充一顆鐵劑就足夠了。
缺鐵性貧血的朋友請不要再吃紅肉來補血了,避免原本已經虛弱的身體再徒增心臟病、癌症、糖尿病和早死的危險。
參考文獻:
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陳惟華醫師的愛家園:http://lovingclinic.blogspot.tw/2014/05/blog-post_7.html