Temporary Influences on Meditation I was wondering, in the case of a beginner in meditation, how much having eaten sugar might affect meditation quality? Also, I wonder what else -- in terms of states altering the mind like tiredness or sexual arousal -- might affect meditation quality. What are the things to avoid to preserve meditation quality?
The vinaya probably talks more about food. In the suttas the stock phrasing is ''moderation in eating'' is associated to good condition with minduflness, like that

https://www.buddha-vacana.org/sutta/anguttara/04/an04-037.html


  "And how does a monk know moderation in eating? There is the case
  where a monk, considering it appropriately, takes his food not
  playfully, nor for intoxication, nor for putting on bulk, nor for
  beautification, but simply for the survival &amp; continuance of this
  body, for ending its afflictions, for the support of the holy life,
  thinking, 'I will destroy old feelings [of hunger] &amp; not create new
  feelings [from overeating]. Thus I will maintain myself, be blameless,
  &amp; live in comfort.' This is how a monk knows moderation in eating.


https://www.buddha-vacana.org/formulae/bhojan.html