naitat purvarsayas cakrur
na karisyanti capare
nirambur dharayet pranan
ko vai divya-samah satam
na—not; etat—this; purva-rsayah—the sages before you, such as Bhrgu; cakruh—executed; na—nor; karisyanti—will execute; ca—also; apare—others; nirambuh—without drinking water; dharayet—can sustain; pranan—the life air; kah—who; vai—indeed; divya-samah—celestial years; satam—one hundred.
Even saintly persons like Bhrgu, born previously, could not perform such severe austerities, nor will anyone in the future be able to do so. Who within these three worlds can sustain his life without even drinking water for one hundred celestial years?
It appears that even if a yogi does not drink a drop of water, he can live for many, many years by the yogic process, though his outer body be eaten by ants and moths.
Link to this page: https://prabhupadabooks.com/sb/7/3/19