可能是20多年前吧,我和內人到一家中餐館用餐。喝了幾口酸辣湯,額頭立刻冒出冷汗,人也覺得暈暈的。直覺的反應就是,「味精!」。

所以,當內人看過前一篇味精有害嗎之後,就提醒我當年不愉快的經驗,要我做進一步的查證。

果不其然,不但是網上熱討,連科學報告也多到讓人難以置信。

怎麼一個已被美國聯邦食品藥物管理局(FDA)定位為 ”Generally Recognized As Safe”「一般認為安全」的添加物,竟然還有這麽多人能拿到研究經費?

更令人詫異的是,這些論文的研究動機,幾乎都是因為味精可能對健康有害。譬如,糖尿病,血管硬化,肥胖,等等。

但,希望大家不要過度反應。因為,絕大多數的研究報告是以老鼠做實驗。所以,其結論不見得適用於人。

但有幾篇是用人做實驗或調查對象,就值得一提。我把它們的標題和重要的結論,列舉如下:

Effect of systemic monosodium glutamate (MSG) on headache and pericranial muscle sensitivity

No muscle pain or robust changes in mechanical sensitivity were detected, but there was a significant increase in reports of headache and subjectively reported pericranial muscle tenderness after MSG. Systolic BP was elevated in the high MSG session compared with low MSG and placebo. 食用味精後,沒有檢測到肌肉疼痛,或機械性敏感度的變化。但頭痛的報告,及主觀報導骨膜肌肉壓痛,有顯著的增加。與低量味精和安慰劑相比,高量味精會使心臟收縮壓升高。

Obese women have lower monosodium glutamate taste sensitivity and prefer higher concentrations than do normal-weight women

Obese women required higher MSG concentrations to detect a taste and preferred significantly higher MSG concentrations in a soup-like vehicle. 肥胖的婦女需要較高濃度的味精,才能嘗出味道,而且顯著地喜好湯裡有較高濃度的味精。

Can dietary supplementation of monosodium glutamate improve the health of the elderly?

A number of studies have examined the potential usefulness of l-glutamate, added to food in the form of monosodium glutamate (MSG), in promoting better nutrition in the elderly and in patients with poor nutrition. Some positive effects have been observed. 許多研究探討將味精加入食物,來促進老年人和病患的營養。有些正面的效果已被觀察到。

這第三篇是認為,添加味精可以提高老年人的食慾,進而改善他們的營養。所以,是很難得的一篇正面的報告。

看了這麼多報告和討論之後,我的結論,也是我對讀者的建言是:

無需恐慌。就如FDA所說的,味精在一般情況下,對大多數人是無害的。但是,如果你還是有顧忌,那就繼續地告訴店家“NO MSG Please”。只不過,請不要像我當年一樣,未經證實就認定,用餐之後的不舒服,是因為MSG。畢竟,心理作用可以是一個很大的因素