Buy canned tomatoes with no salt added, then feel free to add as much salt as you like. If you added enough table/kosher salt to reach the sodium levels in processed foods, you wouldn’t be able to even consume it. Processed foods are “formulated” to taste the way you expect (read: chemicals and other nasty additives), so you can’t readily tell how full of sodium the product is.

Making homemade tomato sauce is about the easiest thing you can do. I use cans of salt-free tomatoes, onions, garlic, carrots, herbs, red wine, etc, making a huge batch and freezing 3-cup portions. It defrosts beautifully, and is far healthier than anything I can get in a grocery.

As far as cooking pasta goes, there’s nothing particular magical about the boiling point – it’s just as hot as you can get the water going, and in this case, hotter = better. It’s easier to make your pasta al dente.

But that’s all secondary – pasta is, by itself, a bland food and strongly benefits in flavor from some salt. And even though you’re adding a lot of salt to the pot, the vast majority of it is going to be poured off when you drain your noodles.

The healthiest and tastiest option is usually to try to limit the salt in your food that doesn’t come out of your own saltshaker. But you can usually be very liberal with your own supply.

Water boils when the vapor pressure of the water gets to be as big as the pressure of the atmosphere, so in other words…vapor bubbles grow.

You must heat the liquid with solutes higher to get the vapor pressure in it to equal the atmospheric pressure, so it has a higher boiling point.

Sorry, I’m a nerd.