The idea/proverb that diet and medicine share the same origin: proper nutrition prevents and helps cure illness.
医師は患者に『医食同源』だから、バランスの良い食事を勧めた。
The doctor told the patient, 'medicine and food have the same root,' recommending a balanced diet.
この店は地元の食材を使い、医食同源を掲げている。
This restaurant uses local ingredients and promotes the principle of food-as-medicine.
祖母はいつも医食同源だから野菜をたくさん食べなさいと言っていた。
My grandmother always said that food is medicine and urged me to eat plenty of vegetables.