With a couple of exceptions, items will be discribed in terms of the spell an item duplicates.  ? indicates an item I've never used, or I'm unsure of.  What the various baits are for is covered under Ryu's profile.

Healing

Herb - Casts Cure
HelpBall - Casts Cure2
Extract - Casts Cure4
Van. Extract - Casts Cure3
Moon Drop - Casts CureX
Biscuit - Casts CureX and Defense-UpX

Gained by hunting

Roast - Casts Cure4
Antler - Cures poisen?
Beef - Casts Cure2?
Meat - Casts Cure?
SpareRib - Casts Cure 4
Tendon - Restores 20 AP, does 20 HP damage?
Egg - Casts Heal
Chicken - Casts Cure2?

Gained by fishing

Sardine - Casts Cure
Unagi - Casts Cure2
Mackarel - Does nothing
Bait - Reduces HP to 1
Tuna - Cures poisen
Minnow - Restores 20 AP, does 20 HP damage
Snapper - Casts Heal
Pile Worm - Casts Cure4

Cure Conditions

Antidote - Cures poisen
Tear Drop - Cures Zombie
Vitamn - Cures curse
Cure All - Casts Heal
Life Plant - Casts RenewX

Combat only

F. Spice - Casts Flame
Shave Ice - Casts Freeze
Frizbee - Casts S. Boom
Fire Rock - Casts Fireball
Kamakaze Ball - Casts Typhoon
Ice Chunk - Casts Hail
Pan Pizza - Casts Attack-Down on all foes
Octopus - Casts Attack-Up on whole party
Poupourri - Casts Angel
Medicate - Casts Attack-Up
Shaker - Casts 8.0

Restore AP

White Fruit - Restores 20 AP, does 20 HP damage
Wise Ball - Restores 100 AP

Odd ones out

Smoke - Casts Smoke
Divide Ball - Undoes Shaman combos
Condition Up - Raises Condition to Super
Tolen - Used for the game with the tree-hosue carpenter
Charcoal - Useless
Whale Cake - More useless than Charcoal

Etc. items (must worn to have any effact; effect ends when taken off)

Dark Earring - Protects from Sleep
Kramer Bracelet - Protects from Zombie
Diamond Braclet - Unknown
Collar - Reduces frequency of random encounters?
Life Bracelet - Protects from Death; Regenerate 1 HP with every step
Shiny Bracelet - Protects from everything but Death
Love Bracelet - Regenerate 1 HP with every step
Holy Scarf - Reduces frequency of random encounters
Charm - Protects from Curse
Dream Bracelet - Sometimes protects from magic

Hero Belt - raises Attack power by 10 points
Fast Shoe - raises Vigor by 10 points
Guts Belt - raises Guts by 10 points
Wise Hoop - raises Wisdom by 10 points
Iron Bracelet - raises Defense by 10 points
Wind Bracelet - raises Vigor by 10 points

PAR (permanent attribute raisers)

Dinker - raises Agility by 1 point
Power Food - raises Strength by 1 point
Miso Soup - raises Wisdom by 1 point
Guts Ball - raises Guts by 1 point
Stamina - raises Stamina by 1 point

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