Many people think of grapefruit as sour. It's not. Grapefruit pith is sour. Without it, a grapefruit is sweet and delicious. It also has far more minimal effect on blood sugar than it otherwise should, for yet to be determined reasons, and is a great food for a diet.
Here's how to eat a grapefruit just as you would an orange. A food hack, if you'll indulge the term, that saves a lot of slicing and sugaring.
Step 1: Peel the Fruit
Not very complex. Peel the grapefruit as you would an orange. Thanks to the thick skin, it usually peels quite easily.
Step 2: Remove Pith From the Top Half
One you've removed the skin, you should have a denuded, and very sour fruit in your hands.
Grab on to the pitch near the very top of the fruit, as indicated by the image note below. If you're careful, you can actually peel off the pith, as seen in the second image. Generally, one can only get most of the top half of the pith with this method.
The third image shows the results.
Step 3: Split and Peel Some More
At this point, you might want to hold the fruit in some paper towel. It's going to start to leak and get messy.
Split the grapefruit in half. Grab the remnants of the stem, noted below, and use that as a starting point to peel off more pith. You can see how it works in the second image.
Step 4: Enjoy!
When you're done, you should have a juicy, sweet grapefruit.
Take off a slice as you would an orange and enjoy.