Saludable vs. sano
The Spanish words saludable and sano both translate to healthy in English. The usage of these two words, however, differ slightly in context.
Saludable
B1Saludable refers to something that promotes health or is beneficial to maintaining good health.
Es importante tener una dieta saludable para mantener un buen estado físico.
(It's important to have a healthy diet to maintain good physical shape.)
Hacer ejercicio regularmente es muy saludable.
(Exercising regularly is very healthy.)
Un ambiente saludable es vital para el crecimiento de los niños.
(A healthy environment is vital for children's growth.)
Sano
A2Sano primarily refers to a state of being free from illness or disease, it can also be used roughly equivalently to saludable.
Mi abuela es muy vieja pero todavía está sana.
(My grandmother is very old but she is still healthy.)
El médico dijo que estoy sano después de la revisión.
(The doctor said I am healthy after the check-up.)
Una relación sana es la base para un matrimonio feliz.
(A healthy relationship is the foundation of a happy marriage.)
Summary
Saludable and sano both refer to a state of wellness, but saludable typically emphasizes habits or lifestyles that promote good health, while sano denotes an absence of illness or poor health and may suggest a state resulting from good health practices.