Pulse Testing

Dr Arthur Coca, a leading American allergist, stated that his wife once reported that her pulse raced after eating certain foods. On this simple observation this great, pioneering doctor — who bridged the gap between clinical ecology and conventional immunologically-oriented allergy work comfortably — built a very interesting technique for detecting allergies, especially to foods.

Because Coca identified clearly a group of patients who had food allergies, ascertained that it ran in families and found no antibodies or other humoral agents to explain the reaction (nor yet have been), he called it familial non-reaginic food-allergy. A further characteristic of this type of allergic reaction is that it frequently raises the pulse rate. It is a very widespread phenomenon in the population: Coca put it as high as 90 per cent on circumstantial evidence.

He gave two important factors as the basis of his discovery, pointing out the dependability of the heart rate as a constant, if all other factors remain equal:

1.     The daily pulse range (the difference between the slowest and fastest pulse rate of the day) is rarely greater than 16 beats per minute.

2.     The daily maximum, remarkably, does not vary by more than two beats per minute.

Coca goes on to say that if the daily range of the pulse exceeds 20 and the daily maximal counts per minute vary by more than two beats, the patient is practically certainly affected with an allergy of the non­reaginic type. Furthermore, if the maximal count is 88 or higher, this is good corroborative evidence and the diagnosis can be upheld.

It must be pointed out that all this refers to a resting pulse rate and that there must be no other manifest clinical condition (such as a fever, heart disease, thyroid excess, anaemia, etc.) that would account for a high or variable pulse rate.

As Coca observed, a patient with allergies may present a completely normal pulse-record for several days on an unrestricted diet, though this is rare. We now know that if this occurs it is due to the ‘masking’ phenomenon (see hidden allergy).

Coca’s method has two aspects. First, he advocates a charted survey of the pulse over several days, the patient taking his or her pulse before getting out of bed in the morning, before each meal, twice after each meal (30 and 60 minutes afterwards) and then on retiring. This record may then be studied in the light of the above criteria. The chart we use in my own clinic is shown in Table below. It is the chart of a 55-year-old woman with arthritis. It shows a range of 28 beats. Also you may note that each time she ate banana her pulse rate increased sharply, and she did indeed turn out to be allergic to banana. She was also allergic to tea, milk, egg and beef, but these caused no reaction on this survey, presumably due to the masking effect.

 

It is difficult to identify specific allergens by means of a chart such as this. It serves only as a general, guide to the case. If by chance, however, it shows periods of normal pulse rate (such as on Day 1 and Day 6), the foods eaten before these periods may be selected as ‘safe’ and if the patient concentrates on those foods he or she may then have a steady baseline upon which to project individual feeding tests.

Coca carried out individual food tests on the basis of five small meals a day, consisting of one single food to be tested at each sitting. He recommended small portions so that the reaction, if there is one, clears more quickly. The resting pulse is used and must be counted for a full minute. It is recorded before ingesting the food and again 30, 60 and 90 minutes afterwards. Naturally the patient should avoid any provocative activities in the interim, otherwise con­fusion may occur, though it is not neces­sary to sit still for the entire one-and-a-half hours.

Safe foods may be used cumulatively. That is, foods that do not raise the pulse may be eaten along with the new food being tested. The time of day and also the sequence in which foods are tested is unimportant, Coca stated, though today we benefit by being able to suggest avoiding foods from the same family within the same two-day period, in case inadvertent cross-reaction and masking occurs.

Essentially this is a simple method and can easily be carried out by the individual on him- or herself. However there are one or two pitfalls. For example, cumulative productive reactions can occur. That is, a food that has little or no effect at first may, if eaten repeatedly as a ‘safe’ food, steadily increase the pulse rate. This problem can usually be sorted out by rotating safe foods.

Environmental factors may also confuse the issue.  It may appear that a food is causing a reaction when in fact it is due to something in the room at the time of testing.  It is important to keep conditions as consistent as possible, to avoid this difficulty.