佛弟子为什么不能吃葱蒜？Why Buddha's disciples cannot eat onions & garlic?

 This article I found, draws reference to Suramgama Sutra. These are extracts.

Quote from Suramgama sutra:-

Translated as and with Personal Deduction added :- 

Now from Suramgama Samadhi Sutra, extract: 

Translated as:- 

BUT [scientific view] : 

I have not found what the [五辛] mentioned by Buddha actually refers to. 

Only the interpreted versions highlighted  them as : 

葱、蒜、韭、薤、兴渠 ~ 

Onion, garlic, leek, scallion, Xingqu (asafoetida).

The "Anti" alleged that the smell after ingesting these Five "Xin", will deter Divine but draws hungry-ghosts to One's sides. Thus will hinder achieving Samadhi.

Also these 5-Xin are said to "start-up" Desires!

I do not seek to Question Buddha's teachings, BUT would like to know "HOW MUCH or What Quantity if Ingested of these Five-Xin, will give rise to the problems stated in the Suramgama Sutra/ Suramgama Samadhi Sutra?

Dear all, do remember if a substance or food has Medicinal properties then it is not classified as Poison as in the Five precepts.

Go think and Enjoy!

With metta

Om Guru Lian Sheng Siddhi Hom

Lama Lotuschef