What is the best diet for a 28 year old male who is moderately active
and works out in the gym 3-4 times a week to follow in order to
eliminate his gut and pronnounce his abs. He is 6 feet tall, 172lbs,
in excellent health, and good shape overall.

thanks!

Rather than dieting, I suggest you focus on building more total body
muscle - all the exercise in the world won't show those abs if there
is a layer of body fat over top.  Most "diets" are largely focused on
calorie deficits, and if deficient in muscle building nutrients, can
start . Building more body muscle overall - is the best fat burning
strategy you can use. And it burns the fat 24x7. Use Weight Training
to max exertion point [don't overdo it!] twice a week. I prefer free
weights as they work several muscles at once. Weight machines are
designed to isolate one muscle group and can lead to muscles getting
out of balance; and overstaining any one muscle group.