Yoma8: 5
עֻבָּרָה שֶׁהֵרִיחָה מַאֲכִילִין אוֹתָהּ עַד שֶׁתָּשִׁיב נַפְשָׁהּ. חוֹלֶה-מַאֲכִילִין אוֹתוֹ עַל פִּי בְקִיאִין, וְאִם אֵין שָׁם בְּקִיאִין, מַאֲכִילִין אוֹתוֹ עַל פִּי עַצְמוֹ עַד שֶׁיֹּאמַר: ,,דַּי”.
If a pregnant woman smelled [food or drink and requested it] they feed her until she recovers. A sick person —- they feed him according to [the advice of] experts, but if no experts are present, they feed him relying on his own opinion until he says, “Enough.”