The Monarch caterpillar’s food source of choice is the milkweeds (common milkweed, Asclepias syriaca, pictured). It not only thrives from the nourishment of its feast of their tender, young leaves, but absorbs substances from the food that make the royal insect foul-tasting and poisonous — great traits for repelling predators.
I am unaware of the human-equivalent edible effect (unless we are going to count things like “garlic breath”), but there is the figurative nourishment of gratitude: to recognize the generosity and kindness of others reproduces and strengthens the same in ourselves. Additionally, the feast of this self-perpetuating adaptation guards against the vagaries of our character, the foibles and graver flaws that make an uncompromising world a harsh, cruel, and bitter one as well. This sentiment is not original, but like many things that endure, it is worth iterating, iterating, iterating, until it is the song we do not hear but feel in that unconscious way of the best things in life.
May we always feast as Monarchs, eating to live, and may we always show our gratitude, to live well.