Possible Clues:

• Venice's leaders take up heresy of shunning the flesh
• Serving a meat. I abandoned ... this?
• Diet adopted by Leo Tolstoy and George Bernard Shaw
• Visit eager man (anag.)
• Saving meatier cooking -- or rejecting it
• A meat serving I arranged out of order for this?
• Serving meat a blunder, entertaining one given to this?
• Vitamins, eg, are developed for this diet
• A meat serving I changed as result of this, possibly