European Journal of Clinical Nutrition (2000) 54, 81±86
ß 2000 Macmillan Publishers Ltd. All rights reserved 0954±3007/00 $15.00
www.nature.com/ejcn
Ten-year trends in vitamin and mineral intake from forti®ed
food in German children and adolescents
W Sichert-Hellert1*, M Kersting1, U Alexy1 and F Manz1
1
Research Institute of Child Nutrition (FKE), Dortmund, Germany
Objective: We investigated time trends in consumption patterns, and energy and nutrient intakes (protein, fat,
carbohydrates, added sugars, vitamins A, E, C, B1, B2 and B6, niacin, folate, calcium and iron) from forti®ed
food in children and adolescents between 1987 and 1996 in Germany.
Design: Mixed longitudinal survey (DONALD study) with 3 d weighed dietary records (n ˆ 2062 from 594
subjects), one subject per family per year chosen by random.
Setting: Dortmund (Western Germany) district cohort.
Subjects: 285 males, 309 females; mean age 6 y (2 ± 13 y).
Results: Almost all children and adolescents consumed forti®ed food irrespective of the year studied. With the
exception of vitamin E, signi®cant time trends in the proportions of nutrient intakes from forti®cation were
observed. The forti®cation of food with vitamins A, C, B1, B2 and B6 and niacin raised the already adequate
intakes from non-forti®ed food (100% to 150% of reference intake values) by 20 ± 50%. The forti®cation of food
with vitamin E and folate raised the low intakes from non-forti®ed food (about 50% of reference intake values) to
about 80% (folate) and 100% (vitamin E) of the references. Forti®cation of food with calcium and iron was not
signi®cant (< 10%), but while total intake of calcium was adequate, total intake of iron remained critical.
Conclusions: Since the nutrient intake of the population of children and adolescents studied is adequate with
respect to vitamins A, C, B1, B2 and B6, niacin and calcium, forti®cation seems inef®cient, while forti®cation of
food with vitamin E and folate, but not iron, improves an inadequate intake.
Sponsorship: The DONALD study is supported by the German Federal Ministry of Health and the North-RhineWestphalian Ministry of Science and Research.
Descriptors: forti®ed food; vitamin intake; mineral intake; diet record; children; adolescents; time trends
European Journal of Clinical Nutrition (2000) 54, 81±86
Introduction
A common de®nition of forti®ed food is given by Segen
(1992): `Any food that has been supplemented with essential nutrients either in quantities that are greater than those
present normally, or which are not present in the forti®ed
food. The supplementation of breakfast cereals with iron
and vitamins is an example of forti®ed food. Forti®ed food
includes also enriched food to which various nutrients have
been added to compensate for those essential nutrients
removed by re®nement or processing.' Nowadays, the
terms `forti®ed' and `enriched' are used interchangeability
(FAO, 1996). The forti®cation of food on a wide scale
started in Germany with multivitamin juices in the early
1980s. Forti®ed beverages are still the food group with the
greatest variety of forti®ed products or brands. Forti®ed
milk products were introduced in Germany as early as
forti®ed beverages, but the diversity remained comparatively narrow.
*Correspondence: W Sichert-Hellert, Forschungsinstitut fuÈr
KinderernaÈhrung Dortmund (FKE), D-44225 Dortmund, HeinstuÈck 11,
Germany.
E-mail: [email protected].
Guaruntor: W Sichert-Hellert.
Contributors: WS-H initiated the evaluation, analysed the data and was
primarily responsible for preparation of the paper. MK took part in the
interpretation and the discussion of all results. UA assisted in the writing of
the paper. FM designed the DONALD study and is head of the DONALD
study team. All authors participated in preparation and subsequent revision
of the paper.
Received 26 May 1999; revised 4 August 1999; accepted 9 August 1999
Although forti®ed products have played an increasing
role in food marketing in Germany since the 1980s, data as
to the consumption of forti®ed food is not available.
Furthermore there are only a few newer studied dealing
with the consumption of forti®ed food to be found and
these are either focused on single groups of products, for
example breakfast cereals, or on nutrient intake in adults.
Long-term data on changes in forti®ed food supply or
consumption patterns is neither available for adults nor
for children and adolescents.
Therefore we evaluated in 3 d weighed dietary records of
2 ± 13 y-old children and adolescents from the DONALD
study (Dortmund Nutritional and Anthropometric Longitudinally Designed study) diversity and time trends in the
consumption of forti®ed food products (Sichert-Hellert et
al, 1999). Here we investigate time trends in nutrient intake
from forti®ed food between 1987 and 1996 in the
DONALD study.
Subjects and methods
Subjects
The sample for this report was taken from the DONALD
study. Details of the study have been described elsewhere
(Kersting et al, 1998b). In short, the DONALD study aims
to collect detailed and repeated data on diet, metabolism,
growth and development from health subjects between
infancy and adulthood. The study started in 1985 with
children and adolescents of different ages participating in
Vitamin and mineral intake from forti®ed foods
W Sichert ± Hellert et al
82
purely anthropometric studies of our institute. Since 1986,
yearly cohorts of 30 ± 40 healthy infants have been
enrolled. Mothers are recruited in maternity wards or are
informed by other study participants without selection. The
DONALD study sample comprises mainly upper social
class families. About 35 (45)% of the mothers (fathers)
have a grammar school education and 21 (39)% a university or graduate professional quali®cation.
The study is purely observational and non-invasive as
approved by the International Scienti®c Committee of the
Research Institute of Child Nutrition. Between 1987 and
1996 a total of 2835 dietary records (one record per year
per subject) from 634 subjects aged 2 ± 13 y were collected
in the DONALD study. For the present evaluation only one
record of a subject of participating family was chosen
randomly leading to a ®nal sample of 2062 records from
594 subjects (mean repeated records per subject 3.5; 128 ±
262 subjects per year; mean age 5.3 3.5 ± 6.6 3.2 y; 285
males and 309 females; see Figure 1).
Data analysis
SAS procedure (Version 6.11) were used for data analysis.
Group speci®c intakes were calculated from the individual
means of the three record days. Results are mean values
( s.d.). Ten-year time trends in intake were tested with a
sign test (Cox & Stuart, 1955) and results were labeled as
( ‡ )=( 7 ) if a signi®cant (P < 0.05, two-sided) increase=
decrease with time was found.
With only a few exceptions, the intake of the different
nutrients from forti®ed food (as a percentage of total
intake) did not vary with sex or age (Wilcoxon test, n.s.).
Therefore results are presented for all subjects per year,
regardless of sex or age. To evaluate reported nutrient
intake in our subjects, the latest (prepublished) dietary
reference intakes were used: AI for calcium (Yates et al,
1998); and EAR for vitamins B1, B2 and B6, niacin and
folate (Yates et al, 1998). For iron and vitamins C, A and E
we used RDAs from the previous edition (National
Figure 1
Research Countil, 1989) because there are no new data
available at present.
Nutrition survey
In the DONALD study food consumption was assessed
with 3d consecutive weighed diet records as described
previously (Kersting et al, 1998b; Alexy et al, 1998). In
short, parents of the children or the subjects themselves
weighed and recorded all foods and ¯uids consumed, as
well as leftovers (electronic food scales, 1 g). Original
product information, for example on wrappers and cartons,
was kept by the participants and collected by a dietitian
together with the diet record. Semi-quantitative recording
(for example numbers of scoops, spoons) was allowed if
weighing was not possible. However, more than 90% of the
recorded food items were weighed in 87% of the records.
Week days (70%) and weekend days (30%) were proportionally distributed in the sample.
To check the validity of dietary recording, the ratio of
reported energy intake (EI) and predicted basal metabolic
rate (BMR) is recommended (Goldberg et al, 1991). We
used measured weight and height to predict BMR according to age- and sex-speci®c formulas given by Scho®eld
et al (1985). In our sample mean EI : BMR ratios of
1.40 0.24 (< 6-y-olds), 1.48 0.26 (males: 6 ± 13-yolds) and 1.43 0.25 females: 6 ± 13-y-olds) were found,
indicating plausible dietary information compared to ranges
given for acceptable results of dietary surveys in these
subgroups, 1.28 ± 1.79, 1.39 ± 2.24 and 1.30 ± 2.10, respectively (Torun et al, 1996).
Nutrient contents of recorded non-forti®ed and forti®ed
food items were stored in our nutrient database `LEBTAB'
(3660 different food items including 1340 commercial
infant food varieties at present). Nutrient contents of
staple foods were taken from standard nutrient tables,
those of commercial food products from product labels or
estimated by simulated recipes from the ingredients listed
by the manufacturers. Added sugars were the sum of added
mono-, di- and oligosaccharides. In some products we
Energy and nutrient intake from forti®ed food as percentage of total intake in 2 ± 13-y-old participants of the DONALD study.
European Journal of Clinical Nutrition
Vitamin and mineral intake from forti®ed foods
W Sichert ± Hellert et al
could not distinguish between natural and forti®ed nutrient
contents because the product labels lacked speci®c information, for example vitamin C in fruit juices. Therefore
nutrient intake due to forti®cation was slightly overesimated in this evaluation. However, the overall concentration of added nutrients in forti®ed products was higher than
that stated, in order to compensate for nutrient destruction
during shelf life.
Here food products were de®ned as forti®ed if enriched
with at least one of the following nutrients: vitamin A or
provitamin A carotenoids (here summarized as vitamin A),
vitamins E, B1, B2, B6 or C, niacin, folate, calcium,
potassium, magnesium, phosphorus or iron. However, forti®ed potassium, magnesium and phosphorus were only
added in some energy drinks and were considered irrelevant for nutrient intake in our sample. Nutrient supplements
and medicine containing nutrients were excluded from this
evaluation.
Results
In 90 ± 98% of the records per study year at least one
forti®ed food item was found, in the 10-y study period, our
subjects consumed a total of 472 different forti®ed products. In the 10 y studied, mean energy intake ranged from
5.72 1.68 ± 6.18 1.64 MJ=d (1368 403 ± 1477 392
kcal=d) with no signi®cant changes over the years.
Forti®ed nutrient intakes in percentage of total intake
With respect to forti®ed food we found signi®cant time
trends. Mean energy intake from forti®ed food increased
from 6 ± 9% (P < 0.0001) of total energy intake (Figure 1)
and intake of added sugars almost doubled (from 10 ± 19%;
P < 0.0001). However, fat intake from forti®ed food (about
8%, n.s.) remained quite constant.
With the exception of vitamin E, the amount of all
forti®ed nutrients in total nutrient intake increased signi®cantly with time (Figure 2). Intakes of forti®ed vitamins
B1, B2 and B6 and niacin showed almost parallel increases
over time from 8 ± 19% of total intake in 1987 to 20 ± 32%
in 1995 (Figure 3). In comparison to other vitamins of the
B-group, forti®ed folate had a slighter increase from 19%
of total intake in 1987 to 29% in 1995. Intake of forti®ed
vitamin E was highest in 1993 (about 40% of total intake)
but decreased to about 30% at the end of the study. The
intake of forti®ed vitamin C increased from 13% of total
intake in 1987 to 29% in 1995. Among the forti®ed
vitamins, vitamin A and niacin showed the smallest contribution to total intake, with maximal values of 17 ± 18%.
Forti®ed calcium increased in time but never exceeded 5%
of total intake. However, for forti®ed iron there was a
pronounced increase from 1992 onwards to about 13% of
total intake in 1996 (Figure 2). With the exception of
vitamin A and iron, the amounts of all forti®ed nutrients
in total intake decreased in the last year of the study period.
83
Nutrient intake in percentage of reference values
To evaluate the importance of forti®cation to the nutrient
supply of our sample we calculated individual intakes of
forti®ed nutrients as well as total nutrient intakes, both in
percentages of references. For vitamins A, C, B1, B2 and
B6 and niacin, total intake was well above 100% of the
respective references (Table 1). Total intakes of calcium
and vitamin E failed to meet the reference values by about
10% in some years, whereas total intakes of iron and of
folate almost always failed to meet references by about
20% (Table 1). Over the study period we found signi®cant
positive time trends for the total nutrient intakes as percentages of references only for vitamins B1 and B6 and
niacin (Table 1). However, with the exception of vitamin E,
intakes from all forti®ed nutrients increased signi®cantly
(Figures 2 and 3).
Discussion
Our evaluation offers an insight into time trends in nutrient
intakes from forti®ed food in German children and adolescents over the last 10 y. This analysis is only practicable
Figure 2 Vitamins C, A and E, calcium and iron intake from forti®ed food as percentage of total intake in 2 ± 13-y-old participants of the DONALD
study.
European Journal of Clinical Nutrition
Vitamin and mineral intake from forti®ed foods
W Sichert ± Hellert et al
84
Figure 3
study.
Vitamins B1, B2 and B6, niacin and folate intake from forti®ed food as percentage of total intake in 2 ± 13-y-old participants of the DONALD
using both prospective quantitative dietary records and a
speci®c and continuously updated nutrient database. This
may be the reason why there are only a few studies
concerning the intake of forti®ed food. Some are con®ned
to single food groups, for example breakfast cereals
(Morgan et al, 1981; McNulty et al, 1996; Nicklas et al,
1995; Moynihan et al, 1996; Ortega et al, 1996), while
others focus on nutrient intake from forti®cation in adults
(Subar & Bowering, 1988; Stanton & Keast, 1989; Block et
al, 1994; Cuskelly et al, 1994). Long-term data on forti®ed
food consumption patterns is neither available for adults
nor for children and adolescents.
Nutrient intake compared with other studies
Total nutrient intakes in the DONALD study are similar to
other representative cross-sectional studies using dietary
records. Greek children (2 ± 14-y-old) have much the same
mean intakes of iron and vitamin C, but higher intakes of
vitamin A (Roma-Giannikou et al, 1997). American children and adolescents (2 ± 19 y-old) have comparable
intakes of vitamins A and C and calcium (Munoz et al,
1997). Allowing for the lower average age in the DONALD
study sample (5.3 ± 6.6 y), 9 ± 13-y-old Spanish children
have comparable intakes of calcium, iron and vitamins A,
E, B1, B2 and B6, niacin and vitamin C (Ortega et al,
1996), and 11 ± 12-y-old British children have comparable
calcium intakes (Moynihan et al, 1996). Moreover the
macronutrient patterns of another sample of 1 ± 18-y-old
subjects from the DONALD study are typical for the
German population in these age groups (Kersting et al,
1998a).
Consumption of forti®ed food
Our study participants consume a typical part of the
forti®ed food supply available in Germany. In a market
survey in 1994 we found a total of 288 forti®ed products:
44% beverages (including instant beverages), 20% sweet
foods, 18% breakfast cereals, and 12% dairy products
(Kersting et al, 1995). In the same year the participants
in the DONALD study consumed 158 different forti®ed
Table 1 Intake of vitamins and minerals as percentage of recommendations in 2 ± 13-y-old participants of the DONALD study in the total
diet (forti®ed food only)
Vitamin as percentage of recommendations
Minerals
Year of DONALD
A
E
C
B1
B2
B6
Niacin
Folate
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
Recommendationa
Trend-totalb
Trend-forti®edb
113 (12)
122 (21)
127 (23)
123 (22)
130 (26)
116 (9)
119 (23)
116 (24)
114 (23)
116 (23)
RDA
0.06
0.008
83 (28)
94 (34)
93 (38)
91 (41)
98 (44)
103 (47)
104 (49)
103 (49)
100 (44)
96 (40)
RDA
0.1
0.03
196 (33)
196 (42)
212 (56)
192 (63)
201 (69)
203 (60)
207 (63)
216 (78)
211 (79)
208 (70)
RDA
0.2
0.0001
135 (33)
141 (40)
143 (45)
139 (49)
139 (47)
142 (49)
148 (55)
151 (61)
151 (63)
153 (63)
EAR
0.0003
0.0001
221 (38)
238 (51)
240 (55)
247 (64)
245 (61)
239 (60)
250 (68)
255 (76)
251 (77)
237 (74)
EAR
0.1
0.0001
193 (41)
199 (52)
209 (63)
213 (73)
208 (70)
214 (73)
222 (82)
227 (92)
224 (96)
224 (95)
EAR
0.0001
0.0001
275 (25)
278 (35)
278 (38)
277 (45)
276 (44)
285 (46)
299 (56)
296 (62)
295 (65)
295 (67)
EAR
0.0005
0.0001
82 (22)
87 (27)
90 (33)
89 (34)
85 (31)
84 (28)
86 (31)
86 (33)
86 (35)
81 (31)
EAR
0.31
0.0001
a
Yates et al (1998). bSign test (Cox and Stuart, 1955); P-values; all trends with P < 0.05 are positive.
European Journal of Clinical Nutrition
Ca
89 (1)
93 (2)
99 (2)
97 (3)
96 (3)
93 (3)
94 (2)
99 (4)
94 (5)
87 (4)
AI
0.5
0.0001
Fe
77 (2)
77 (3)
71 (3)
69 (4)
71 (4)
74 (4)
74 (4)
72 (5)
77 (10)
78 (11)
RDA
0.06
0.0001
Vitamin and mineral intake from forti®ed foods
W Sichert ± Hellert et al
food items with about the same food group proportioins
(42% beverages, 15% breakfast cereals, 10% sweets=biscuits and 6% dairy products). During the 10 y DONALD
study period the number of recorded different forti®ed
products or product diversity doubled, but the proportional
3 d records with at least one forti®ed food item remained
stable (90 ± 98%). This means that almost all children and
adolescents eat some sort of forti®ed food products. Irrespective of the year studied, `beverages', `fats=oils' and
`breakfast cereals' were the food groups with the highest
product diversity.
Energy and nutrient intake from forti®ed food
Along with increasing forti®ed product diversity we
observed a signi®cant increase in energy intake from
forti®ed food, up to about 10% of total energy intake in
1996. Many of the forti®ed products consumed were low in
fat but high in added sugars, for example about 20% of the
carbohydrate intake from forti®ed food came from added
sugars. Our market study in 1994 showed 56% of forti®ed
products with added sugars (Kersting et al, 1995). Food
marketing probably uses forti®cation to raise the image of
high sugar products (for example sweets, sweetened beverages) for consumers.
Nutrient intake and recommendations
The latest North American data on dietary references
intakes for calcium, vitamins B1, B2 and B6, niacin and
folate (Yates et al, 1998) differ considerably from the
previous US-RDA edition (National Research Council,
1989). Due to new ®ndings in preventive medicine the
new reference values for folate are about twice as high as
the previous RDA, and calcium references differ depending
on age (about 40% lower for 1 ± 3 y-olds, and about 10%
higher for 9 ± 18 y-olds). In contrast, the new references for
vitamins B1, B2, B6 and niacin are reduced by about 30 ±
50%.
We identi®ed four typical situations of nutrient intake in
our study population: (a) Intakes of vitamin C, B2 and B6
and niacin were well above the reference values with more
than 150% derived from non-forti®ed food alone and an
additional amount of about 50% from forti®ed food. Under
these circumstances forti®cation seems to be unnecessary;
(b) Intakes of vitamin A and B1 were about 100% of
reference values derived from non-forti®ed food and additionally about 20 ± 50% from forti®cation. Taking into
account safety considerations in the estimation of reference
values (National Research Council, 1989), forti®cation
with vitamin A and B1 seems to be inef®cient here; (c)
For vitamin E and folate, non-forti®ed food supplied about
50% of reference values and forti®cation raised the intakes
to about 100% (vitamin E) or 85% (folate) of the references. Here, forti®cation plays an important role in nutrient
intake; and (d) Total intake of calcium can be considered as
adequate, but total iron intake was critical. However, in
both cases forti®cation is not signi®cant (almost lower than
10%) with respect to nutrient intake.
In forti®cation in Germany, critical nutrients such as
iron or folate are under-represented. In 1994, only 7% of
288 products were forti®ed with iron and 46% with folate,
but 62% were forti®ed with vitamin C (Kersting et al,
1995).
Time trends in nutrient intake investigated here showed
small but signi®cant uniform increases in intakes of forti®ed calcium, iron, folate and vitamins A, E, B2 and C, but
they were not accompanied by signi®cant increases in total
nutrient intake. This may indicate time trends in food
choice towards non-forti®ed food with lower amounts of
these essential nutrients.
85
Food forti®cation policies
The American Dietetic Association distinguishes between
three complementary approaches to enhancing the nutritional adequacy of populations at risk: (a) nutrition education; (b) forti®cation of staple foods, and (c) use of nutrient
supplements. The use of supplements is an individual
approach and largely self-directed. In contrast food forti®cation is a public health approach designed to increase
the nutrient intake for a targeted population by increasing
the nutrient quantity in the food supply (Stephenson &
Guthrie, 1994). The US Food and Nutrition Board in 1974
and the FAO in 1986 almost agree on the de®nition of
stipulations for forti®cation, for example: (a) the intake of
the nutrient is below the desirable level in the diets of a
signi®cant number of people; (b) the food used to supply
the nutrient is likely to be consumed in quantities that will
make a signi®cant contribution to the diet of the population
in need; (c) the addition of the nutrient is not likely to
create an imbalance of essential nutrients; (d) there is
reasonable insurance against excessive intake to a level
of toxicity (FAO, 1996; Mertz, 1997). Furthermore, a
Codex Alimentarius Commission postulates that added
essential nutrients should not lead to either excessive or
insigni®cant intake and should not be used to mislead or
deceive the consumer as to the nutrional merit of the food.
In industrialized countries, food forti®cation is often justi®ed by rapidly changing lifestyles and by increasing
reliance on more highly processed foods, but there is no
general consensus regarding the extent to which food
forti®cation should be practised and fear of over-forti®cation is rising as manufacturers seeks to use forti®cation as a
marketing tool (FAO, 1996).
In Germany there is no forti®cation of staple foods with
the exception of margarine (vitamins A, E and D) and table
salt (¯uoride, iodine), because the general social consensus
is lacking. In the forti®ed food items marketed in Germany
we found large variations in the numbers and amounts of
forti®ed nutrients, which were mirrored in the forti®ed
products consumed in our study sample. In a considerable
number of forti®ed products, especially forti®ed beverages,
amounts of single forti®ed nutrients reached more than
100% (maximum 660%) of daily reference doses in an
average portion, while other forti®ed nutrients made up no
more than about 30% from the same product. In about 50%
of the forti®ed products at least six nutrients were added
simultaneously (Kersting et al, 1995). The present evaluations of the diet records in the DONALD study together
with our food market observations seem to point to overforti®cation without a sound nutritional policy Ð at least
for the population of children and adolescents in Germany.
In particular the wide user of multi-vitamin-foods used in
forti®cation violates the principles of food forti®cation
outlined above.
Food forti®cation may give consumers a misleading
feeling of security in their nutrient intake and may prohibit
necessary changes in overall food choices with respect to
overall prevention and health promotion (for example
decrease in fat intake and increase in fruit and vegetable
consumption). However, an overall change in food choices
is necessary in German children and adolescents, as is
European Journal of Clinical Nutrition
Vitamin and mineral intake from forti®ed foods
W Sichert ± Hellert et al
86
shown in another evaluation of the DONALD study which
found high proportions of fat, saturated fatty acids, animal
protein and added sugars and low proportions of complex
carbohydrates and dietary ®bre (Kersting et al, 1998a). As
to the essential nutrients investigated here, in most cases
the total intake remained quite stable over the 10 y study
period, although the intake of forti®ed nutrients and the
variety of forti®ed products increased. This might be a hint
to changing food patterns in our sample towards nonforti®ed food with lower nutrient contents.
Our data shows that the stipulations of food forti®cation
policies outlined above are not evident in the present day
diet of children and adolescents in Germany. To meet
special needs (iron, folate) in some target population
groups the use of single nutrients or at least well-composed
nutrient supplements might be considered instead of forti®cation. However, at present there is no agreement in the
scienti®c community as to whether to fortify food or to
educate people or to use supplements, but it is mostly
agreed upon that priority should be given to a balanced
food choice combined with nutritional education, especially in children and adolescents.
Acknowledgements ÐWe are very grateful to Christa Chahda and Ruth
SchaÈfer for collecting and coding the dietary records in the DONALD
study.
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