Hi,

The below 2 statements sound correct

Consumption of any particular food reverses hardening of the arteries

Consumption of any particular food will reverse the hardening of the arteries

so why it it that writing the sentence in the future tense changes the singular reverses to reverse ?

that's not a singular construction. future tense verbs ALWAYS follow "will" with the infinitive form of the verb (minus the "to" in front):
i am happy.
i will be happy.

future tense verbs don't conjugate at all, actually. every future tense verb has exactly one form, which looks the same for ALL possible subjects.
this is one of the blessed simplicities of the english language. (unfortunately, there are plenty of complexities to balance out those simplicities)