That literally means by following the given measures one can avoid occurrence of diseases.

Padarthchandrika defines vega as,

Initiation of urgency of Mutra (urine), Purish (faeces), etc naturally on its own is called as ‘Vega’.

Hemadri explains vega as ,

Presence of urgency of voiding mutra, purish is known as vega.

Aacharya Dalhan defines vega as ,

Natural escape from its own site is known as Vega.

As mentioned by acharya Indu (Critical writer of ashtanghruday)

रोगा: सर्वेपि जायन्ते वेगोदीरणधारणै:॥

This means, all the rogas are produced due to vega udiran or vega dharan, that makes one impossible to be swastha (healthy). Where, Vega are natural urges and udiran means balata preran (facilitating forcefully when there is no urge or little urge present) and Dharan means balaat rodhan (Holding back the natural urges forcibly when present).

Thus, by avoiding vega dharan, roga becomes incapable of producing.