The faulty diet behind acidity:

Eating at irregular times

Eating incompatible foods (eg: fish followed by milk shake)

Skipping meals

Eating late at night
Keep your acidity at bay by avoiding these foods:

Packed, tinned and stale foods- like ready to eat foods; tinned vegetables etc.

Eggs and fried meat

Deep fried foods like samosas and pakodas

Bread and bakery items

Chocolates and toffees

Coffee/ tea

Onion and tomatoes

Pickles and Chutneys

Frozen items

Fermented foods

Dairy products like butter cheese, cream, ice-cream

Carbonated beverages
Other than these foods, there are some food habits that you should follow to avoid hyperacidity:

Avoid eating at night just before sleep. Make sure you eat 2-3 hours before getting to bed.

Avoid late night food binges.

Avoid eating more than 2 meals in a day (breakfast 9-10 am; dinner 7.30 -8.00 pm).

Avoid drinking water during meals or just after.

Avoid drinking cold water.

Avoid eating food too fast.