According to Coca, if you eat something to which you are allergic, your pulse-rate will speed up. To determine whether you are allergic to foods, take your pulse before a meal and then at several intervals after eating. Unfortunately, since many factors can cause an increase in pulse-rate it may be difficult to isolate the specific items. Also, remember that sometimes a delayed reaction can take as long as several days to appear. If the pulse does not increase within two or three hours it may not mean you are not allergic only that there is not a rapid reaction.
Liquids are more likely to produce a fast reaction.
There are a number of dietary tests to identify allergies to specific foods. Such tests often begin with a fast, and then introduce foods one at a time, to observe whether there are any allergic reactions. A variation on this approach, if you are suspicious of a particular food, is to eliminate that food and related food, from your diet for about two weeks, then eat a lot of it and see if you get a reaction. Two kinds of reactions may occur. First, you may observe withdrawal symptoms on eliminating the food from your diet.