SQL - Merging fields from two tables into one, including dup

Rails
#1

Hi,

I have two tables, nutritions and food_options.
nutritions has two fields, fooditem_id, taken and .
food_options has two fields, fooditem_id and taken.
fooditem_id in nutritions and food_options will point to id in
food_items table(third table).

I want to select all records from nutritions and food_options into a new
table, C with Fields fooditem_id and taken. This means I need to
combine the values of fooditem_id in nutritions and fooditem_id in
food_options into one field (fooditem_id), including the duplicates in
both tables.

EX:
nutritions
id fooditem_id taken
1 23 1
2 23 1

food_options
id fooditem_id taken
1 34 1

C
id fooditem_id taken
1 23 1
2 23 1
3 34 1

How can I do this?

thanks,
srinath