Plain hummus may be low histamine, but sometimes there are high histamine ingredients added. A basic hummus will be made from steamed chickpeas, ground sesame seeds, oil, lemon juice, garlic, salt, and cumin, all of which are generally low histamine; but anyone can be sensitive to any one ingredient. If an oil you don’t tolerate is used or an aged cheese is added, for example, the level of histamine in hummus can be raised immediately.
So if you’d like to enjoy hummus on a low histamine diet, I highly recommend either making your own or trying a store-bought brand that you know is freshly-made, with tolerated low histamine ingredients. Another workaround is to make hummus with cauliflower in place of chickpeas, though the flavor isn’t quite the same.