The Taoists realized thousands of years ago that plants of the alliaceous family were detrimental to humans in their healthy state.
The 5 forbidden vegetables are leeks, chives, shallots (spring onion), garlic and onions.
In his writings, sage Tsang-Tsze described the Alliums as the “five fragrant or spicy scented vegetables” – that each have a detrimental effect on one of the following five organs – liver, spleen, lungs, kidneys, and heart. Specifically, onions are harmful to the lungs, garlic to the heart, leeks to the spleen, chives to the liver and spring onions to the kidneys.
Plants of the Alliaceous family are pungent vegetables containing five different kinds of enzymes which cause reactions of repulsive breath, extra-foul odour from perspiration and bowel movements, and lead to lewd indulgences, enhance agitations, anxieties and aggressiveness, especially when eaten raw.
Garlic and onions are both Rajasic and Tamasic, and are forbidden to Yogis because they root the consciousness more firmly in the body.
This is based on teachings found in the Brahma Net Sutra, the Surangama Sutra and the Lankavatara Sutra. In modern times this rule is often interpreted to include other vegetables of the onion genus, as well as coriander.
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