Five a Day refers to the international campaign to get people to eat fruits and vegetables. The mention of “six times that” suggests that there are thirty fruits and vegetables hidden in this word search.
They are:
Asparagus
Avocado
Banana
Blackberry
Blueberry
Broccoli
Cantaloupe
Carrot
Cauliflower
Celery
Cherry
Corn
Cucumber
Eggplant
Grape
Kiwi
Lemon
Mango
Onion
Orange
Pear
Pepper
Pineapple
Pomegranate
Potato
Pumpkin
Raspberry
Strawberry
Tomato
Watermelon
Note that this list disregards names of fruits and vegetables that are part of longer names, such as PEAr or pineAPPLE.
Once you have found all thirty words, the unused letters, reading from top to bottom, left to right, spell out the phrase DESSERT SHORTENED TO FROYO, which gives the answer FROZEN YOGURT.