You've heard this phrase a thousand times:

"Abs are made in the kitchen!"

No, abs are revealed by what you're doing in the kitchen. They're made in the gym, like any other muscle group.

This expression comes from two things:

1. You can do a million reps of various ab exercises, but if you have too much fat covering them you won't see a six pack.
2. Some people who are very lean have abdominal definition even if they don't train them (or train at all).

So it's pretty easy to jump to the conclusion that the secret to having abs is getting lean, which most people believe to be solely diet thing.

But That's Not Quite Right

Tell me, what foods should I eat to hypertrophy my abs? Like, really heavy foods? Obviously, abs have to be trained to grow bigger, which in turn makes them more visible.

Some people can even get lean and still not see their abs. And others (like me) can have a full six pack even at a higher body fat level.

That's because having that six pack is dependant both on having a thinner layer of fat and having separation between the sections of the "pack." And that separation occurs when the muscle bellies of your abs are thicker than the tendinous attachments (the lines between the abs). Since the muscle bellies can get thicker if you train them, but not the attachments, training can give you that separation you need.

Some people are born with more natural separation than others and might not need to directly work their abs to have a visible six-pack. And others who have thinner abdominal muscle bellies might not have that separation even when they're super lean.

If you're lucky and born with good separation then you might not need to train your abs directly; all you need is to get super lean. But most people will need to work their abs to get that look. Furthermore, the direct ab work will make the abdominal bellies thicker which also means that you won't need to get as lean to have ab definition.