Answer

Yes, during Upvas, many Jains generally avoid brushing teeth with toothpaste because toothpaste may contain substances considered unsuitable during fasting, and brushing can also involve swallowing water accidentally.

Explanation

In Jain practice, during Upvas one usually avoids:

• Food
• Unboiled water
• Items with taste or additives
• Anything that may disturb the strictness of the fast

Because toothpaste has taste and ingredients, it is usually avoided during strict Upvas. Some people may gently clean the mouth with plain boiled water, depending on their family tradition, sect, and the level of strictness they follow.

Spiritual Understanding

Upvas is not only about not eating. It is also about self-control, simplicity, alertness, and reducing attachment to bodily comfort.

Takeaway

For a strict Jain Upvas, it is best to avoid toothpaste and brushing in the usual way. If needed, follow the guidance of your Guru, family tradition, or local Jain practice.