*****
代糖，不是真實的糖，它是以「騙」的方式讓你的舌頭以為吃到糖。(註４)
雖然人體不能消化，但能代謝出去，對人體是無害的(註５)
我聽過許多對「代糖」的謠言，說它人工合成、不自然、會引發疾病。
我上舉的兩種代糖，維基就記載一大堆闢謠的歷史。
我想借題發揮一下。
有些標榜"有機、自然"食物廣告的渲染，說什麼東西含化學成份不健康，
其隱台詞是：牽涉到"化學"就有毒、十惡不赦，許多人由是心生恐慌。
然而，這是一種刻意誤導，讓大眾對化學產生不正確的認知。
關於化學，我認為可有這三點正面認識。
第一點，它是認識物質的一種基本之微觀視角。
所有物質都是可以用化學形式描述，也就說所有物質皆有「化學成份」，
可是，這不能意謂著它有毒。
比如說，水是H2O、氧是O2、葡萄糖、蔗糖、澱粉和纖維素是碳水化合物。
它們不會因為稱呼變了，生成毒性。
但也有可能是有人把「化學成份」定義成「人造」。
那就要問：人造就不好嗎？
人天天接觸的牙膏、漱口水、加氯自來水等等，總不能當毒吧。
相反地，純天然就對人體無害嗎？
番茄葉子雖自然但有毒，糖、鹽無毒但長期吃多了，也會危害身體。
因此，要回歸到務實的科學驗證。
而這便是第二點，化學可作為安全檢驗的一種標準。
經由化學研究的定量、定性分析和大量實驗驗證，人們能了解人體承受物質的允許範圍。
比如，數值低於多少、或數值高於多少會造成人體傷害。
不可否認，現今我們所吃的食物，是否達安全標準得靠化學來測定。
以阿斯巴甜為例(註６)，
歐盟規定成人的阿斯巴甜每日容許攝取量為40mg/kg，美國FDA 則規範為50mg/kg。
一位體重75公斤的成年男性，需要飲用大約21罐（7.3公升）無糖可樂，
才會達到FDA規定的每人每日的攝取上限。
第三點，化學是醫學的基礎知識。
這是化學造福人類的一面，讓人類延長壽命，脫離病苦。
科學知識，向來是中性的(非善非惡)。
以上三點，旨在說明化學的中性，及正面用途：為安全把關、治病扶傷。
反之，它亦可被有心人士用來為非作歹。
水能載舟、亦能覆舟，端看我們能不能用於正途，但不能將化學等於邪惡。
*****
話題再回到代糖。
我們懷著開放的態度，討論代糖有害與否，要抨擊、要推翻都沒關係，
但請提出強而有力的證據，用科學說話。
同理，誇安全、誇益身也一樣，像是有人說：
由於代糖中的蔗糖素(Sucralose)是來自蔗糖，所以它沒問題。
這裡得再次強調：東西安不安全與"是否來自自然"無關！
蔗糖素之所以安全(註７)，而因為它通過廣泛的實驗，而不是因為它是由蔗糖製造。
如同水來自於氫的化合，水與氫特性不同。
因此，回歸用科學說話，因為它才是目前最可靠的方法。
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註３：
In 1879 Fahlberg, working with Remsen in a post-doctoral capacity,
made an accidental discovery that changed Remsen's career.
Eating rolls at dinner after a long day in the lab researching coal tar derivatives,
Fahlberg noticed that the rolls tasted initially sweet but then bitter.
Since his wife tasted nothing strange about the rolls,
Fahlberg tasted his fingers and noticed that the bitter taste was probably from
one of the chemicals in his lab.
The next day at his lab he tasted the chemicals that he had been working with the previous day
and discovered that it was the oxidation of o-toluenesulfonamide he had tasted the previous evening.
He named the substance saccharin and he and his research partner Remsen published
their finding in 1880. Later Remsen became angry after Fahlberg, in patenting saccharin,
claimed that he alone had discovered saccharin.
Remsen had no interest in the commercial success of saccharin, from which Fahlberg profited,
but he was incensed at the perceived dishonesty of not crediting him as the head of the laboratory.
2.
英文維基：糖精
Saccharin was produced first in 1879, by Constantin Fahlberg,
a chemist working on coal tar derivatives in Ira Remsen's laboratory
at the Johns Hopkins University.
Fahlberg noticed a sweet taste on his hand one evening,
and connected this with the compound benzoic sulfimide on which he had been working that day.
Fahlberg and Remsen published articles on benzoic sulfimide in 1879 and 1880.
In 1884, then working on his own in New York City,
Fahlberg applied for patents in several countries,
describing methods of producing this substance that he named saccharin.
Two years later, he began production of the substance in a factory
in a suburb of Magdeburg, Germany.
Fahlberg would soon grow wealthy, while Remsen merely grew irritated,
believing he deserved credit for substances produced in his laboratory.
On the matter, Remsen commented,
"Fahlberg is a scoundrel. It nauseates me to hear my name mentioned in the same breath with him."
註４：
維基：阿斯巴甜