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for the Promotion of Health
The Journal of the Royal Society
http://rsh.sagepub.com/content/124/2/74
The online version of this article can be found at:
DOI: 10.1177/146642400412400211
2004 124: 74The Journal of the Royal Society for the Promotion of Health
Noor Aini Mohd Yusoff, Shelagh M Hampton, J W T Dickerson and Jane B Morgan
The effects of exclusion of dietary egg and milk in the management of asthmatic children: a pilot study
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INTRODUCTION
In the UK there are over three million people with
asthma.
1, 2
In adults and children a clinical response
can be triggered by a wide variety of agents. These
include dietary and environmental allergens, viral
infections, exercise, exposure to fumes and other
irritants, certain drugs, food, drink and food
additives.
3
In asthmatic children aged less than two years, an
adverse reaction to cows’ milk is reported to be the
most common ‘allergic reaction’ followed by an
adverse reaction to eggs.
4
Anderson
5
and Weeke
4
reported that amongst the factors that determine
asthma prognosis the following were important:
age, immune status, sex, mother’s age at child-birth,
infections, other allergic diseases, and signs and
symptoms of food allergy. Anderson
6
commented
that up to the early 1990s little interest and
investigative effort had been directed towards a
possible role for foods in the provocation of atopic
asthma. Perhaps the general feeling was that inhaled
allergens, rather than those consumed in food, were
more likely to be the main causes and immediate
sensitivity reactions to foods were reported to be
less frequent in children with asthma than in those
with eczema. The results of only a few clinical trials
seem to have been published and priority has been
Abstract
Current understanding of the use of exclusion diets in the management of asthma in children is
limited and controversial.
The aim of this study was to examine the effects of excluding eggs and milk on the occurrence of
symptoms in children with asthma and involved 22 children aged between three and 14 years
clinically diagnosed as having mild to moderate disease. The investigation was single blind and
prospective, and parents were given the option of volunteering to join the ‘experiment’ group,
avoiding eggs, milk and their products for eight weeks, or the ‘control’ group, who consumed their
customary food.
Thirteen children were recruited to the experimental group and nine to the control group. A
trained paediatrician at the beginning and end of the study period assessed the children. A seven-
day assessment of food intake was made before, during and immediately after the period of dietary
intervention in both groups. A blood sample was taken from each child for determination of food
specific antibodies and in those children who could do so, the peak expiratory flow rate (PEFR) was
measured.
Based on the recommended nutrient intake (RNI), the mean percentage energy intake of the
children in the experimental group was significantly lower (p<0.05) in the experimental group. After
the eight-week study period and compared with baseline values, the mean serum anti-ovalbumin
IgG and anti-beta lactoglobulin IgG concentrations were statistically significantly reduced (p<0.05)
for both in the experimental group. In contrast, the values for anti-ovalbumin IgG in the control
group were significantly increased and those for anti-beta lactoglobulin IgG were practically
unchanged. The total IgE values were unchanged in both groups.
Over the study period, the PEFR in those children in the experimental group able to perform the
test was significantly increased, but no such change was noted in the children in the control group
who could do the test.
These results suggest that even over the short time period of eight weeks, an egg- and milk-free
diet can reduce atopic symptoms and improve lung function in asthmatic children.
74 RESEARCH Diet in the management of asthmatic children JRSH 2004; 124(2): 74-80
JRSH
The journal of The Royal Society for the Promotion of Health
The effects of exclusion of dietary
egg and milk in the management of
asthmatic children: a pilot study
Authors
NNoooorr AAiinnii MMoohhdd YYuussooffff
,
Department of Nutrition and
Dietetics, Faculty of Allied
Health Sciences, Universiti
Kebangsaan Malaysia, Jalan
Raja Muda Abdul Aziz, 50300
Kuala Lumpur, Malaysia
SShheellaagghh MM HHaammppttoonn
, School
of Biomedical and Molecular
Sciences, University of
Surrey, Guildford, Surrey GU2
7XH, England
JJ WW TT DDiicckkeerrssoo
n, School of
Biomedical and Molecular
Sciences, as above
JJaannee BB MMoorrggaann
, School of
Biomedical and Molecular
Sciences, as above
CCoorrrreessppoonnddiinngg aauutthhoorr::
Jane B Morgan
Received 6 May 2003, revised
and accepted 2 December
2003
Key words
Asthma, children, diet,
exclusion, milk
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Diet in the management of asthmatic children ARTICLE 75
The Journal of The Royal Society for the Promotion of Health JRSH
on the effectiveness of dietary intervention
during pregnancy,
7-10
during pregnancy
and lactation,
11, 12
in infants,
13, 14
and in
children,
15
on the prevention of atopy
development.
No reports have been found in which the
value of eliminating food allergens has
been assessed in the management of
asthma in children. The present study was
undertaken with the defined objective of
determining the potential benefits of
dietary avoidance of egg, and egg products,
and milk and milk products, in reducing
the symptoms of asthma in children.
Allergic reactions are usually mediated
by IgE antibodies to specific antigens.
However, IgE has been found not to be
suitable for general risk screening in
neonates
16
and in older individuals can
give falsely negative and falsely positive
results.
17
Pastorello
18
suggested that
positive skin prick testing (SPT) and
specific IgE levels may be unrelated to
clinical symptoms and may simply be due
to cross-reaction between allergens present
in commercial materials. These reports,
together with an increased recognition of
the value of IgG measurement
19
led us to
measure both total IgE levels, as a check on
previous observations, and food specific
IgG levels in our children.
METHOD
The study design was of a single blind
prospective nature. Parents, children and
the investigator (NMY) were aware of the
study groups to which the children had
been allocated. However, the paediatricians
who saw the children were ‘blind’ in
relation to the study groups during the
pre-study and the post-study assessments
of the children.
Duration of the study
The half-life of IgG antibody is 23 days
and the residual time of mast cells is two
to three months.
20
Therefore, to enable any
change to occur during the study, eight
weeks abstinence from egg and milk was
considered reasonable. For children, it was
anticipated that compliance with the diet
would be difficult if the study lasted longer
than this.
Subject recruitment
Seventy-one asthmatic children aged three
to 14 years were recruited from the 111
asthmatic children attending the
Outpatient Department in the Royal
County Hospital and the Frimley
Children’s Centre. These subjects were
screened for selection into the study, based
on food specific IgG antibody levels. The
baseline values against which these levels
were assessed were obtained in 19 non-
atopic non-asthmatic children (no
personal and family history of atopy or
asthma) chosen from a total of 45 children
approached.
Of the 71 asthmatic children tested, 43
(61%) were identified as possible
candidates for dietary intervention as their
anti-ovalbumin IgG concentrations were
above the mean concentrations found in
the non-atopic non-asthmatic children
(>500 ug/ml), an arbitrary cut-off point
for selection. Of the 43 possible subjects,
22 agreed to participate in the study.
Parents were given the option of allocating
their children into the experimental (diet
intervention) or control (no diet
restriction) groups respectively. As a result,
13 children were included in the group on
the diet with nine in the control group.
The children in the experimental group
were advised to adhere to a diet devoid of
egg and egg products and milk and milk
products. Children in the control group
were asked to continue to eat their
customary diet during the eight weeks of
the study.
Anthropometric measurements
The investigator measured the weights and
heights of all the children before the study
began and after it was completed. Weights
(in light clothing) were measured with
calibrated Seca weighing scales and were
recorded to the nearest 0.1 kg. Heights
(standing, no shoes) were measured with
an upright stadiometer and recorded to
the nearest 0.1 cm.
Guidance on egg and milk avoidance
The investigator for the families in the
experimental group produced a booklet on
egg- and milk-free food products. This
booklet was compiled from two British
Dietetic Association publications, Egg Free
Booklet,
21
and Cows’ Milk Free Booklet.
Cows’ Milk/Egg Free Booklet.
22
These
booklets provided lists for various
commercial food items that could be
consumed by the children in the
experimental group. In addition, verbal
advice was given to families when the
investigator (who is a qualified dietician)
met them (see below). Since the timing of
the study coincided with Easter, children
in the experimental group were given a
dairy- and egg-free ‘Chocolate Bunny’ (D
& D London, UK). No dietary advice was
offered to the control families, and if
advice was sought, only that of a general
nature was given.
Dietary supplements
The experimental children were provided
with a hypoallergenic milk supplement
(Pepti-Junior, Cow & Gate, Nutricia,
Trowbridge, Wiltshire, UK) to replace all
milk drinks. A recipe booklet (Cooking
with Pepti-Junior, published by Cow &
Gate, Nutricia) provided parents with
advice on the more versatile use of the
milk supplement. Parents were contacted
regularly for replenishment of the milk
supplements. The children in the
experimental group were also given a
calcium supplement in the form of a tablet
(Calcichew, 500 mg calcium tablet, Shire
Pharmaceuticals Ltd, Andover, Hants, UK),
which was taken on alternate days to
ensure that calcium requirements were
met. In addition, children were advised to
consume a daily helping (4 g) of a yeast
extract (Marmite) in order to obtain the
recommended amount of riboflavin.
Assessment of non-compliance
Monitoring non-compliance was essential
in the experimental children. If a dietary
accident occurred, the parents were asked
to record on a form designed for the
purpose the date and type of eggs and/or
milk products consumed. The investigator
kept regular contact with the parents by
telephone and home visits. This ensured
that the morale of the parents and their
children, especially those in the
experimental group, was maintained
throughout the study.
Recording of energy and nutrient intake
All parents were asked to record their
children’s daily food intake for the first,
fourth and eighth week in a seven-day
estimated ‘food diary’, developed and
validated by the Dunn Clinical Nutrition
Centre, Cambridge, UK. The food diary
was validated by the UK European
Prospective Investigation of Cancer and
Nutrition studies comparing various
dietary assessment methods in nutritional
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76 RESEARCH Diet in the management of asthmatic children
epidemiology.
23, 24
The food diary
contained colour photographs of small,
medium and large portions of 17 foods
pictured on a ten-inch dinner plate.
Parents could choose one of the amounts
shown in the photograph or indicate that
their children consumed less than the
smallest or more than the largest amount
shown. Parents were encouraged to weigh
foods using their home kitchen scale (not
validated) if any food consumed was not
available, or no similar food was available
in the pictures. Parents were given stamped
addressed envelopes to mail completed
food diaries to the investigator.
The food diary was also used to monitor
non-compliance in the experimental group
for the food intake records were checked as
soon as the diaries were received and any
queries were clarified immediately with
parents. The amount of food consumed
and recorded in the food diaries was either
computed directly with portion sizes or
converted into weight (g) using Food
Portion Sizes
25
on the computer
programme, Comp-Eat 4.0 (Lifeline Ltd,
London, UK). Nutrient analysis was
undertaken using this programme and
compared with the Dietary Reference
Values for Food Energy and Nutrients for
the United Kingdom.
26
Intakes of calcium
and minerals and vitamins derived from
supplements were included in the
computed nutrient analysis. Because of the
fact that the children varied in age between
three and 14 years of age and were of both
sexes, the results of the dietary assessments
were expressed as a percentage of the
recommended nutrient intakes (RNI).
22
Clinical assessment
All the children who participated in the
study were invited to Frimley Park
Hospital or Frimley Children’s Centre for
clinical assessment carried out by a
paediatrician or a trained registrar
responsible for running the Out-Patient
Paediatric Asthma Clinic at the Frimley
Children’s Centre. The paediatrician and
registrar were both involved in the design
of the study and the pre- and post-dietary
clinical assessments. They agreed to use
the same methods and criteria to reduce
any bias in their assessment. On both
occasions, one of the two clinicians,
without knowledge of the children’s study
group, evaluated the children using a
standard form for current signs and
symptoms of asthma including the
presence of coughing, nocturnal coughing,
wheezing, the number of asthmatic
episodes during the past eight weeks and
current medication including the type,
dose and frequency of medication.
Peak expiratory flow rate
All the children were assessed for their
ability to perform the measurement of the
PEFR. Those children who were able to
perform this measurement correctly were
given a Mini-Wright Peak Flow Meter
(Clement Clarke International Ltd, UK) if
they did not already own one. Children
who were able to make the PEFR
measurement were asked to record the best
of three measurements taken twice daily
(first thing in the morning and just before
going to bed) on a fortnightly chart. These
charts were mailed to the researcher
(stamped addressed envelope provided)
together with the food diary after the first,
fourth and eighth week of the dietary
intervention period.
Blood sampling and analysis
A 2 ml non-fasting venous blood sample
was taken from the children at the start
and at the end of the intervention period
by one of the doctors or a nurse. The
blood sample was allowed to clot at room
temperature, centrifuged and the serum
aliquoted and frozen at -20°C until the
completion of the intervention period.
The sera taken at the beginning and at
the end of the intervention period were
analysed in the same batch for the
measurement of anti-ovalbumin IgG and
anti-beta lactoglobulin using indirect
ELISA methods.
27
Total IgE was measured
with the CAP system of Pharmacia
(Uppsala, Sweden).
Statistical analysis
The data were analysed using the Statistical
Package for Social Science (SPSS). Paired
Student’s t-test was used to test the
significance of the difference in the
anthropometric and dietary data before
and after exposure to dietary intervention
in the two groups of children. As the data
for the specific food IgG, IgE and total IgE
antibodies were not normally distributed
despite being logarithmically transformed,
statistical analyses were performed using
the non-parametric, Mann-Whitney U
tests and Wilcoxon signed rank sum tests.
Ethical approval
Ethical approval for the study was
obtained from the South West Surrey
Regional Health Authority Ethics
Committee in March 1995 and from the
North West Surrey Local Research Ethics
Committee in August 1995.
RESULTS
Subjects
The mean age and gender of the 22
children in the experimental and control
groups are given in Table 1. The range of
ages of the children in each group was
rather wide and each group contained
children of both sexes and more boys than
girls. There was no significant difference
between the changes in the mean heights
of the children in the two groups at the
end of the study compared with those at
the beginning. However the control
children gained a significant amount of
weight during the study period whereas
those on the special diet showed a mean
loss in weight (Table 1). It is to be noted
that some individual children in both
Table 1
Gender, height and weight of asthmatic children in the study during the
eight-week dietary intervention
Experimental Control
Number of children 13 (8 male, 5 female) 9 (7 male, 2 female)
Mean age (range), years 6.5 (4-14) 5.0 (3-8)
Mean height change (range), cm 0.6 (0-1.65) 0.5 (0-1.2)
Mean weight change (range), kg –0.16 (–1.2-1.15) +0.34* (–0.6-1.2)
*Mean weight gain in the control group was significantly higher in the experimental
group (p<0.05)
JRSH The Journal of The Royal Society for the Promotion of Health
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Diet in the management of asthmatic children RESEARCH 77
groups lost weight during the study.
Dietary supplements
None of the control children received or
consumed vitamin or mineral
supplements. All the children on the egg-
and milk-free diets received and
consumed 500 mg calcium on alternate
days and two of the children took multi-
vitamin supplements daily containing
vitamins A, D, E, C, thiamin, riboflavin,
niacin, pyridoxine and pantothenic acid.
Two children in this group consumed soya
milk as their main drink. The
hypoallergenic formula (Pepti-Junior) was
not popular as a milk alternative eaten
with cereals with ten of the children. It
was said to be ‘unpalatable’ when eaten in
this way. One child complained of being
sick after consuming it, and another
refused to drink it after tasting it for the
first time despite the mother masking it
with flavourings. Alongside this response,
three children requested additional
supplies after the first consignment and
tolerated it for the first few weeks before
rejecting it. Mothers utilised the formula
in cooking with the help of the recipes
provided.
Compliance with the egg- and milk-free
diet
Of the 13 children who were on the diet,
six appeared to have inadvertently
consumed small amounts of egg and milk
products during the study period. These
foods were in the form of cakes consumed
once or twice in family gatherings. The
remaining seven children strictly followed
the diet for the whole of the eight weeks.
No significant differences were observed in
the levels of food-specific IgG antibodies
in those children who complied fully with
the diet compared with those who
complied partially.
Energy and nutrient intake
The results of the 21-day food records
from the two groups of asthmatic children
are summarised in terms of the
percentages of the RNI in Table 2. The
children on the experimental diet
consumed a significantly lower percentage
of energy than the controls. The protein
intake of both groups of children was high,
with some children in both groups having
more than 300% of the RNI. It is to be
noted that the mean percentages of the
RNI for most nutrients consumed by the
children on the experimental diet were
lower than those of the controls and this
was particularly true for the amounts of
iodine and vitamin A. Although the value
for calcium intake exceeded 100% of the
RNI in the children on the experimental
diet, there were some children who, in
spite of taking the supplement, consumed
only 61% of the RNI. At least one of the
control children also consumed a similar
amount of calcium. The amount of zinc
consumed was inclined to be low in
children in both groups. In spite of being
told to take a supplement containing
riboflavin, at least one child in the
experimental group consumed only 49%
of the RNI for this vitamin. Some children
in both groups, and particularly those on
the restricted diet, had low intakes of
Table 2
Percentage of RNI consumed by the experimental and control asthmatic children derived from 21-day food record
data. Values include the contribution from supplements (see text for detail)
Experimental Control
Mean % ± SD Range Mean % ± SD Range
Energy 84 ± 14* 55-105 100 ± 11 84-113
Carbohydrate 116 ± 9 103-131 106 ± 4 99-111
Protein 182 ± 60 106-319 251 ± 52 197-356
Fat 102 ± 9 88-115 116 ± 7 108-125
Calcium 109 ± 30 61-149 155 ± 63 60-275
Iron 125 ± 57 60-249 133 ± 18 113-165
Zinc 77 ± 32 31-138 95 ± 20 68-119
Selenium 135 ± 45 60-195 168 ± 56 106-277
Iodine 47 ± 22 10-84 122 ± 89 55-330
Thiamine 227 ± 86 134-345 172 ± 36 130-240
Riboflavin 155 ± 89 49-287 189 ± 55 129-279
Nicotinic acid 213 ± 41 125-266 189 ± 28 150-230
Pyridoxine 238 ± 82 145-421 193 ± 43 134-260
Vitamin B
12
188 ± 49 90-255 339 ± 97 180-456
Folate 137 ± 66 73-298 171 ± 53 115-263
Vitamin C 274 ± 153 117-517 241 ± 91 157-376
Vitamin A** 75 ± 39 10-147 171 ± 114 93-435
Vitamin E 113 ± 50 43-213 116 ± 33 76-168
* Mean value in children in the experimental group was significantly (p<0.05) lower than in the control group
** Vitamin A equivalent
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78 RESEARCH Diet in the management of asthmatic children
JRSH
The journal of The Royal Society for the Promotion of Health
vitamin E. By contrast, the amounts of
nicotinic acid, pyridoxine and vitamin C
consumed by the children on the restricted
diet exceeded those of the control
children.
Immunoglobulin concentrations
Results for the analysis of the
immunological data are given in Table 3. In
the children that had been in the
experimental group, the mean serum
anti-ovalbumin IgG concentration was
significantly (p<0.01) lower at the end of
the diet period than it was at the beginning
of the study. This contrasted with the values
in the control group, which increased
(p<0.05) during the study period. Similarly,
the post-study anti-beta lactoglobulin IgG
concentrations for the experimental group
were also significantly (p<0.01) lower at the
end of the study than at the beginning. The
post-study values for this immunoglobulin
for the control group were not significantly
different from their baseline values. The
post intervention values for the total IgE
concentrations were not significantly
different from the baseline values in either
group.
Peak expiratory flow rate
Of the 22 asthmatic children participating
in the study, 11 (50%) were able to carry out
the PEFR measurement correctly (six from
the experimental group and five controls).
Figure 1 shows the mean values for the two
groups of children before and after the
eight-week study period. After completing
the eight weeks on the exclusion diet the
mean value for the PEFR had risen by 22%
(p<0.05) whereas the value for the controls
had decreased by 0.6%. The value for one
child in this group had actually decreased by
25%, which may have indicated a
forthcoming asthma attack.
Other outcomes
One experimental child was able to sleep
undisturbed throughout the remainder of
the study after one week on the diet and
another experimental child’s eczema
improved. Neither of these children
claimed an improvement in their asthma.
It was noted that after the trial was
completed and the experimental children
reverted to their usual diet, several
mothers reported one of the following:
one child had an asthma attack after
consuming a piece of cake, two children
frequently required a beta 2 agonist when
engaged in sports activities, the eczema of
three children got worse and the child
whose sleep had become undisturbed
while on the trial reverted to her earlier
sleep pattern after the trial.
One child from the restricted diet group
and one of the controls had reduced their
intake of a beta 2 agonist over the course
of the study. Both children showed an
improvement in their PEFR value and had
reduced concentrations of anti-ovalbumin
IgG, anti-betalactoglobulin and total IgE
values. The child on the restricted diet
reported improved ‘well-being’ when
engaged in sports activities.
DISCUSSION
In 1968 Rowe and Rowe
28
conducted a
survey on 1,491 asthmatic patients. They
reported that 40% of children under five,
25% of children between five to 15 years,
29% of adults 15 to 55 years, and 40% of
adults over 55 years, had asthmatic episodes
with foods. These results were based on case
histories, skin tests, and response to the
Rowe 1-2-3 elimination diets. They were
convinced that if physicians were more
concerned, they would find that half the
cases of allergic asthma and psychogenic
asthma in adults were caused by an adverse
response to foods.
Van Metre et al
29
evaluated the Rowe
cereal-free 1-2-3 diet along with a high
allergenic foods diet in a double-blind
crossover study on 18 randomly selected
asthmatic adults with no history of
diagnosed food allergy. No difference in
the frequency or severity of asthmatic
symptoms was observed in these subjects
after a three-week period following the
Rowe cereal-free diet. However, Rowe and
Rowe
28
commented that the duration of
Van Metre’s trial was too short and noted
that the body requires a longer period of
time to adapt before any improvement in a
subject’s respiratory symptoms could be
expected.
The present study involved 22 children in
a single-blind diet intervention study of
eight weeks. Their parents allocated the
children to either the experimental group or
the control group. The resulting groups
contained 13 and nine children respectively,
Table 3
Food specific IgG and total IgE concentrations in the serum of asthmatic children before and after the eight-week
dietary intervention
Experimental Control
Mean (SD) Range Mean (SD) Range
Anti-ovalbumin IgG (mg/ml) Baseline 2483 (935) 999-3939 1447 (956) 28-2981
Post diet 1876 (805)* 652-3147 1659 (1033)** 34-3609
Anti-betalactoglobulin IgG (mg/ml) Baseline 223 (182) 13-567 399 (600) 31-1886
Post diet 149 (108)*** 8-343 415 (686) 53-2198
Total IgE (kU/ml) Baseline 1603 (2469) 4-4096 851 (1547) 13-4794
Post diet 1610 (2387) 8-7258 694 (1149) 7-3545
*** Mean value significantly lower in the post diet period compared with the baseline value (p<0.01)
*** Mean value significantly higher in the post diet period compared with the baseline value (p<0.05)
*** Mean value significantly lower in the post diet period compared with the baseline value (p<0.01)
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Diet in the management of asthmatic children RESEARCH 79
The journal of The Royal Society for the Promotion of Health JRSH
with the experimental group containing
children up to 14 years of age and the
control group up to eight years of age.
The study cannot be considered as more
than a pilot because of the small number
of children involved. Of the 111 children
attending the collaborating hospitals, 43
were identified as possible subjects for the
study. After being acquainted with the
requirements of the investigation and the
degree of commitment required by both
parents and children, only 22 agreed to
participate. Those who did were dedicated
to the investigation and problems with the
diet were minimal; rather more parents
(13) agreed to the inclusion of their
children in the diet group than in the
control (9). Ethical considerations
precluded the inclusion of a control group
of non-asthmatic children.
The eight-week study period was used
on the basis that the half-life of IgG is 23
days and the residual time of IgG on the
mast cells is two to three months.
20
Although a period on a diet devoid of eggs
and milk of 12 weeks would have been
preferred, compliance would have been
even more difficult. Over the eight-week
study period, the mean weights of the
children in the experimental group
decreased by 0.16 kg whereas those of the
control group rose by 0.34 kg. The reason
for the loss in weight of the experimental
group was probably that the food
consumption of the experimental group
did not achieve the RNI for energy (84%)
whereas that of the controls did (100%).
The amount of protein consumed by the
experimental group was also lower (182%
RNI compared with 251% for the
controls). It is to be noted that in spite of
being asked to take appropriate
supplements, the intakes of many of the
micronutrients by the experimental group
were below those of the controls. This may
suggest that not all the children on the
restricted diet actually consumed the
supplements. The biggest differences were
for iodine (47% RNI in experimental
children and 122% RNI in controls) and
for vitamin A equivalents (75% RNI in
experimental children and 171% RNI for
controls). This is evidently a matter that
should be given special attention in future
trials of restricted diets in asthmatic
children.
When considering the dietary intake of
the two groups of children it should be
noted that the foods in the experimental
diet were different in taste, texture and
variety, especially those likely to have been
favourite foods such as desserts and snacks
which included cheese, ice cream and
yoghurt. Milk and eggs not only enhance
flavour, but also enhance the texture of
most commercial and home-prepared
foods. A longer study period might have
given time for the children to adapt to the
new foods and hence to increase their food
consumption.
Immunological effect of egg- and milk-
free diet
All the children on the experimental diet
had significantly reduced concentrations
of specific food IgG antibody to
ovalbumin and beta lactoglobulin after
eight weeks on a diet devoid of eggs and
milk. This finding seems to confirm that
antibody measurements can be used to test
for compliance in food exclusion studies.
The changes in IgG were associated with
functional improvement in the five
children on the experimental diet who
were able to perform the PEFR test, which
is a measure of lung function. Admittedly,
these numbers are small, but for each
individual child the effect on well-being
should not be under-estimated. For two of
the children the paediatrician confirmed
an improvement in well-being. The same
children claimed that they were ‘less
chesty’ when engaged in sports activities
and thus required less treatment with a
0
50
100
150
200
250
300
350
PEFR (L/min)
DG pre-intervention n=6
DG post-intervention n=6
NDG pre-intervention n=5
NDG post-intervention n=5
Groups of asthmatic children
Figure 1
Mean peak expiratory flow rate for the experimental group and the
control group of asthmatic children before and after eight-weeks dietary
intervention
PEFR = peak expiratory flow rate
DG = experimental group
NDG= control group
*Post-intervention mean value PEFR was significantly increased from baseline mean
value PEFR for experimental group DG (p<0.05)
*
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beta agonist. One child reported an
improvement in eczema. None of the
children had a change of grading in their
total IgE results. The finding of no change
in the total IgE levels in children, but
clinical improvement correlated with a
decrease in food specific IgG levels, in
decrease in the concentrations of the
corresponding IgG components in the
blood that was associated with functional
and clinical improvements in asthmatic
children. These beneficial changes tended
to be lost when the diet was stopped.
children receiving a milk-free, egg-free diet
seems to confirm the greater reliability of
food specific IgG measurements in the
children.
CONCLUSION
An egg-free, milk-free diet caused a
80 RESEARCH Diet in the management of asthmatic children
JRSH
The journal of The Royal Society for the Promotion of Health
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RSPH Fish & Chip Supper
Harry Ramsden's, Brighton, Sunday 18 April 2004 – 12th Annual Public Health Forum
To kick off the four-day Annual Public Health Forum, organised by the UKPHA and the World Federation of Public Health Associations,The
Society is holding a Fish & Chip Supper on Sunday 18 April at the world-famous Harry Ramsden's restaurant. The supper offers an opportunity
to put aside the pressing health issues that will dominate the week and break the ice with colleagues from around the globe with a traditional
British three-course meal. All Society members living in Brighton or attending the conference are welcome to join us.
To book, send credit card details or a cheque for £19 per person, to
The Royal Society for the Promotion of Health, 38A St George's Drive, London SW1V 4BH
Or email: events@rsph.org
Please mark your correspondence, ‘Fish & Chip Supper’.
74-80 Research_Asthma 2279 5/3/04 2:53 pm Page 80
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