Grapes: sugar, blood and a lift in mood
Grapes are a fruit of quick glucose - and one of the few foods people reliably describe as cheering.
Grapes are a fruit of quick sugar. The glucose in them is available almost immediately, which is why a handful lifts a flagging afternoon faster than almost anything else in the fruit bowl.
What they carry
Beyond the sugar, grapes bring water, potassium, vitamin K and a group of plant compounds - resveratrol among them - that have kept researchers interested for decades. Darker grapes carry more of these than pale ones, so black and red are the better buy.
The liver and the blood
Grapes are traditionally regarded as a food for the blood and the liver, and they have long been given to people recovering from illness. As convalescent food they are hard to beat: easy to eat when appetite is poor, hydrating, and pleasant.
A word on quantity
Grapes are dense in sugar and easy to eat by the bowlful without noticing. A cupped handful is a serving. If you are watching blood sugar, treat them with more care than you would an apple.
Wash them properly. Grapes hold residue in the gaps between the fruit, and a rinse under the tap is not quite enough - soak them a few minutes first.
