Hey dear sister. Nice to see your positive attidude.

In my opinion, coughing up phlegm is the body expelling toxins. My understanding is that the body protects itself from the harmful effects of cooked food by producing mucous. Perhaps you have been eating less, or eating less cooked food, so the body no longer needs to protect itself so much so is expelling it in this way.
Fasting is an extremely effective way of healing the body by the way, especially when combined with colon cleansing (and breath-work). i can send you a link to a guided breathwork audio if you like, which may well also help with your breathing endurance.

Sat Nam
Atma

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