I have noted that many people have food equipped instead of swallow.
This leads me to question whether consuming say six portions of food
at the start of a fight would result in your health constantly increasing during the fight.

Food HP recovery doesn't stack, as far I know. You can use some of them as a supplement to increase health recovery even further, especially those with long lasting effects. I usually use Swallow during battles and food while out of battle or when it is really desperate and I'm out of Swallow and White Raffard's Decoction.

No, it would not. As already noted, healing does not stack. You need to keep an eye on the regeneration icon. When it disappears or gets close to zero, down another piece of food. Food IS more sensible, and more easily acquirable than potions, that's why you see so many people using it.

Also, if you use food fequently for regeneration, the "Gourmet" skill (under General Skills) is invaluable. It allows regeneration for 20 minutes instead of 5/10 seconds. Food portions won't stack, but food regen for 20 min is far superior to the swallow potion. So good, it almost feels like a cheat.

I use the Gourmet skill from the General Skills. It does almost feel like a cheat it's so good. Geralt only needs to rolls a few seconds to regenerate his health mid combat. Best spent skill point. Just hope he doesn't get fat with all that eating!!

Very interesting and informative posts. So in effect, food consumption could make a long, hard fight easier.

Gourmet is very helpful during extended fights. I just finished a contract fight where the monster caused bleeding damage, which is continual damage, and the Gourmet skill helped to offset that damage.

You can stack swallow and food, so i say both.

That is not stacking. That is parallel use. Not the same thing. Swallow will heal N vitality for X seconds and so will food. They do not (together) heal 2*N vitality for X seconds, which is what stacking would do. Though I admit to not having tested this in-game.

You haven't even tested and claim I'm wrong, that is extremely rude and uncalled for.

Don't be such a cry baby. I simply stated that using two items to do the same thing concurrently is not stacking. Unless both items work together additively, it is not.

Both items stack at healing, actually make healing faster!

Keep flaming, mods will appreciate.

Provide evidence. Idiot.