No, the word 'healthful' is not a noun, it is an adjective, a word used to describe a noun as good for the health of the body or mind (healthful exercise, healthful relaxation).
The noun form for the adjective healthful is healthfulness. A related noun form is health.
Healthful is an adjective.
Eating fruit is very healthful
No, health is a noun. The adverb form of the adjective healthy is "healthily." (it is seldom used)
The word healthful has two syllables. Health-ful.
Here's an easy way to remember: People are healthy, food is healthful.
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A healthful snack should be low in sugar and low in cholesterol.
There are a few healthful claims. Some claims like eating right and working out.
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