Does fasting on Saturday for Śani or Thursday for Guru help?

weekday vratas are a traditional way to honour a graha; they help through discipline and devotion, not by bargaining with planets.

Each weekday is ruled by a planet: Sunday the Sun, Monday the Moon, Tuesday Mars, Wednesday Mercury, Thursday Jupiter, Friday Venus and Saturday Saturn. A vrata on that day — often one simple meal, with prayer to the related deity and some dāna — is a long-standing folk remedy. Thursday fasts with yellow food and Bṛhaspati kathā, and Saturday fasts with Hanumān or Śani worship, are especially common.

The real value lies in what fasting builds: self-control, a quieter mind and a weekly habit of remembering God. These do change how you face difficult periods.

Keep it gentle. A partial fast is fine, and anyone who is ill, pregnant, diabetic or on medicines should eat normally and simply keep the prayer. A fast should never harm your health; that is not what the tradition asks.

Source: Vrata tradition; modern practice · Health comes first

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