Subway Parmesan Cheese

Subway's Parmesan Cheese is high in histamine, and it is the aging that does it rather than the milk. Parmesan spends months maturing, which is exactly the condition histamine builds under.

Why subway parmesan cheese is rated high

The ingredient list is two lines long: parmesan cheese and salt. That short list is the whole story, because parmesan is one of the most heavily aged cheeses on any menu. During that long maturing period, bacteria and enzymes steadily break the milk proteins down, and histamine is one of the things that accumulates along the way. Milk starts out low. The process is what makes the finished cheese high, which is why aged hard cheeses sit near the top of nearly every low-histamine avoid list while very fresh unaged cheeses are treated as a completely different situation.

What changes your risk

• The aging is already finished — this cheese was matured for months before it was grated, so it arrives at the store high and nothing at the counter moves it.
• Older and harder tends to mean higher — parmesan sits at the far end of the aging scale, which is why it rates above softer, younger cheeses rather than alongside them.
• A light sprinkle is not a light dose — hard cheese has had a lot of its water driven off during aging, so what formed is packed into a small amount of dry cheese.
• The shaker sitting out is not the issue — this is a dry grated product, so how long it waits on the line is not what sets the level. It came in high.
• Melting or toasting does not fix it — heat can kill bacteria, but it cannot remove histamine that formed while the cheese was aging.

Lower-histamine alternatives

There is no lower-histamine cheese on the rated list at Subway, so this is not a swap-one-cheese-for-another situation. The items here that come out low are Cucumbers, Lettuce and Red Onions. Worth understanding for the wider diet: it is the aging and not the dairy itself that causes the problem, so the length of maturing is the thing to look at whenever you are judging a cheese, and no amount of aging is short enough to make parmesan a low choice.

How to lower the risk

Treat the parmesan as the component that decides the rating of the whole sub, because with a single high-histamine driver in it, nothing else you add can pull the sandwich back down. Building around the items that do rate low here, meaning Cucumbers, Lettuce and Red Onions, is what actually keeps a Subway order in low territory. And do not assume a smaller shake is a smaller problem, since the cheese is concentrated by the same aging that made it high.

Common questions

Is parmesan high in histamine?

Yes, it is one of the highest cheeses on a low-histamine diet, because it is aged for a long time and histamine accumulates during that aging.

Is grated parmesan different from a wedge?

Not in any way that helps. The aging happened long before the cheese was grated, so both carry it.

Is this a lactose problem or a histamine problem?

A histamine one. The rating comes from the maturing process, not from the sugar in milk, so lactose-free products are not the answer here.

Can I make it work by only having a little?

No. Aged hard cheese is treated as an avoid item on a low-histamine diet, and there is no amount that can be called safe.