What is the primary reasoning for some branches of Buddhism advising against eating onions and garlic?

Answer

To maintain mental composure by avoiding foods that stir up passions or cause mental turbidity.

For certain monastic orders within Buddhism, the decision to abstain from onions and garlic is rooted in spiritual discipline rather than digestive science or allergies. The consumption of these pungent vegetables is believed to have an effect on the subtle energy or temperament of the individual. Specifically, they are thought to stir up the passions, increase restlessness, or lead to mental turbidity. The goal of this practice is to maintain a clear, unagitated state that is highly conducive to focused meditation and spiritual practice, ensuring mental equanimity is preserved throughout the day.

What is the primary reasoning for some branches of Buddhism advising against eating onions and garlic?
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