JOURNAL OF ADOLESCENT HEALTH 1992;13:384-388
CONFERENCE PROCEEDINGS
Dietary Habits, Food Consumption, and Nutrient Intake During Adolescence NICOLA
L. BULL, M.A.,
M-SC.,
M.PHIL.,
Adolescents and young adults adopt eating patterns which may well form the basis of their dietary habits for much of their lives. At the same time, this section of the population can come under considerable pressure from the world at large, to conform to the current trends in fashion, language, behavior, or foods. Recent developments in Western dietary practice have tended to leave adolescents vulnerable to low intakes of energy and of some nutrients, as snacking accounts for an increasing proportion of dietary intake. Achieving a balanced diet is more difficult when the most popuiar and widely available snack foods are high in sugar or in fat. Results from major British studies, together with a review of data from other developed countries, support the need for more effective dietary education for adolescents and for children generally. KEYWORDS: Diet
Nutrient intake Energy intake In 1982 the British Ministry of Agriculture, Fisheries and Food (MAFF) conducted a dietary survey of l525 year olds. This study attempted to look, to a limited extent, at attitudes and habits as well as at food consumption, and the full results were published in 1985 (1). This was followed by a major study of the diets of British schoolchildren, conducted under the supervision of the Department of Health. Analysis of this study was completed in 1989 (2). There are a number of common conclusions from these two studies and they are further reinforced by the work A&~ssreprint requests to: Nicola Bull, M.A., M.Sc., 84 Grove Raad, Tting, He& HP23 5PB, England. TG w was presented at the 5th Congress of the lnternatiomd A.wcidon fir Adolescent Health, iuly 3-6, 1991, Montreux, SWitilWld.
Manuscript aaeptd October 17,
1991.
384
1034-139x/9245.00
Published by
F.R.S.H.
of others who have studied the diets of adolescents throughout the developed world (3).
Results The MAFF study of 15-25 year olds began in 1981 when groups of young people were brought together in various parts of Great Britain for informal discussion sessions concerning their eating habits and attitudes. A number of factors were important in affecting the individual’s food consumption pattern: age (that is, within the band selected for the main survey, which was 15-25 years); living accommodation, especially whether or not the individual was still living at home with his or her parents; social class, which might tend to determine the spending power of the subject and the family meal habits; and also region, the part of the country in which the subject lived. A quota design was used, with market researchers in different parts of the country given a defined set of young people to recruit to the study. In this way the participants were a representative sample (in terms of marital status, educational status, and living accommodation) of British young people aged between 15 and 25 years. A detailed recruitment questionnaire provided a record of the demographic and socioeconomic data, and each subject then completed a preceded 2-week dietary diary. A followup questionnaire included questions about the height and weight and history of pregnancy. The report of this study gives a breakdown of food consumption and details of energy and nutrient intakes against a wide range of variables (1). Table 1 shows the intakes of young people in the three age ranges as percentages of the 1979 United Kingdom recommended daily amounts (RDAs) for energy and
QSociety for Adolescent Medicine, I!%? Elsevier Science Publishing Co., Inc., 6.55 .%vcnue rf the Americas, New York, NY IOOIO
July 1992
DIETARY HABITS DURING ADOLESCENCE
Percentage of Recommended According to Age”
Table 1.
Men (age, yrs) 15-18 19-21 22-25 Energy (%) Iron (%) % energy from fat
84 92 42
86 115 42
85 116 42
Amounts Women (age, yrs) 15-18 19-21 22-25 86 71 43
78 69 43
85 78 45
“Bull 1985.
iron. All other nutrients studied were deemed to be
available in more than sufficient quantities for each of these age/sex groups. Energy intakes were between 80 and 90% adequate on average, suggesting that there were some individuals with very low energy intakes. Iron intakes were markedly lower than recommended levels among the female participants, at between 70 and 80% of RDAs, on average. For rneir and women energy from fat was consistently above 42% on average. The levels were not significantly different for the married subjects. The balance of energy nutrients did not alter in a favorable way when the subject reported being on a diet to lose weight. There still appears to be a preoccupation with carbohydrate-rich foods as “fattening foods” (Table 2). The average energy intakes in these groups over the 2 weeks of the study were quite low, but the percentage of energy from fat remained very high. The older group of weight- and diet-conscious women had decreased the proportion of energy from carbohydrate and increased that from fat. When this diet- and weight-conscious group are looked at further, it can be seen that it contains some of the subjects with very low intakes of both energy and dietary iron compared with the recommended levels for women of their ages (Table 2). It is well known that some young women take weight loss to an extreme and thereby endanger their health or their lives. The following dietary features emerged from the British MAFF study of 15-25 year olds: 1. Consumption of alcoholic drinks increased with age and was higher for men. Almost 40% of
the 15-18 year olds as a whole, said that they drank alcohol between once and three times a week and in the age range 22-25 years, 16% were daily drinkers. 2. Consumption of chocolate and other confectionery showed a tendency to decline with age. 3. Consumption of crisps and similar snacks av-
385
eraged 15 grams per day, but ranged up to 105 grams per day. 4. Average daily consumption of meat and meat products was somewhat higher for men than for women. Chicken was the most popular meat, followed by beefburgers and beef. Meat pies, pork, bacon, and sausages also featured significantly within this category. 5. Vegetable consumption was greater by men than by women and increased with age for both men and women. 6. Average fruit consumption decreased slightly with age and, like the consumption levels of cakes and desserts, appeared to be positively associated with social’class. 7. Consumption of eggs averaged the equivalent of approximately two large eggs per week, and the majority were eaten as fried eggs. 8. Cheese (approximately 90% of it hard cheese) was eaten more by the older groups and averaged 30 grams per day over all subjects. 9. Of the survey participants, 18% reported that they never ate breakfast; only 58% said that they ate breakfast every day. When asked which foods they liked but thought that they should not eat, women produced more answers than men; 26% of the female subjects said chocolate, 18% said chips, and 15% said sweets. (The primary reason given by subjects for listing these foods was that they were fattening.) Of the male subjects, 10% said chocolate, 13% said chips, and 8% said sweets. The women were much more foodconscious than the men; more of them thought that they were overweight, and more of them took an Table 2. Percentage of Recommended Daily Amounts (RDAs) and Nutrient Intake for Women According to Age and Dieting Practice“ Aee
range (vears)
15-18 A Energy (%) Energy (Ml/day) Iron (%) % energy from fat
B
19-21 C
A
B
22-25 C
A
B
C
76 76 74 73 67 66 80 77 80 6.8 6.8 6.6 0.6 6.1 6.0 7.2 6.9 7.2 63 65 62 66 63 58 74 74 73 44 42 43 43 41 43 45 44 46
“Bull 1985.
(A = those subjects who considered themselves to be overweight; B = those subjects who reported being on a diet at the time of the study or who said that they always watched their diet; and C = those subjects who considered that they were overweight and who were also on a diet or watching what they ate.)
386
JOURNAL OF ADOLESCENT HEALTHVol. 13, No. 5
RULL
Table 3. Average Intakes of Energy“
Boys(age,yrs) lo-11 (W/day) % RDA
8.67 91
14-15 10.40 90
Girls (age, yrs) 10-11 7.69 90
14-15 7.85 87
RDA, recommended daily amount. “DOH 1989.
interest in the ingredients of processed foods. Some of the survey subjects were concerned about food additives. A second major British survey was conducted among young people during the early 1980s. This time the focus of attention was schoolchildren and the effects of new school meal arrangements. Two age groups were selected which complement the previous study by covering the younger and preadolescent age group. Boys and girls aged lo-11 years and aged 14-15 years were selected, and the final weighted sample consisted of almost 2700 children who provided 7-day dietary records and whose heights and weights were measured. Again, results have been tabulated in the full published report (2), against a range of demographic variables. included here are some of the main features relating to energy and nutrient intakes and dietary patterns. The average daily energy intake of the 14-15 year old boys was higher than that of the younger boys, and the average energy intakes of boys were higher than those of girls in both age groups (Table 3). Mean energy intakes were about 10% lower than the RDAs, but the children were, on average, on or above the 50th percentile of standards for height and well above the 50th percentile of standards for weight, regardless of energy intake. The average proportion of energy from fat ranged from 37.4 to 38.7% across the different age and sex groups, and three-quarters of the children had intakes of fat which gave a proportion of energy from fat exceeding the 35% recommended by a United Kingdom government panel on diet and cardiovascular disease (4). Milk and chips were fhe two main contributors to these fat intakes. Mean iron intakes of girls were below the RDAs, and older girls also had mean riboflavin intakes below the RDA. Girls, especially the older group, had lower average consumption of milk and breakfast cereals, major sources of this vitamin. Milk and cereals together with bread are also important dietary SXUCES of calcium and again, among the older girls,
some 60% had calcium intakes over the 7 days which were below the RDA. The main sources of energy in the diets of British schoolchildren were bread, chips, milk, biscuits, meat products, cake, and puddings. Almost all children recorded consumption of chips, crisps, cakes, and biscuits. Boys consumed more chips, milk, breakfast cereals, and baked beans. Girls recorded more fruit and fruit juice. Reinforcing the trend emerging from the previous study, fizzy drinks and sweets were more popular among the younger children. The Scottish youngsters recorded higher median consumption of beef, soups, milk, cheese, sausages, chocolates, and sweets and lower median consumption of cakes, biscuits, puddings, potatoes, and vegetables of all kinds, when compared with children in the other regions of Great Britain. Chips and milk were the two major items which varied most with socioeconomic variables. Greater median consumption levels for chips were recorded by children whose fathers were unemployed or whose families received supplementary benefit, and children who had school meals or, in the case of the older group, who ate out of school at cafes, etc., rather than having lunch at home or taking a packed lunch to school. Milk consumption was, on average, lower among these same groups. Although the total average daily intakes of energy and nutrients did not vary with the kind of meal eaten at lunchtimes on weekdays, the dietary patterns of foods consumed, and therefore the dietary sources of energy and nutrients, were to some extent dependent on the provision from school meals. Thus, the older children obtained more than onehalf of the chips they ate during the week from school meals and younger children obtained over one-half the buns and pastries they ate from their school meals. The school meal provided, on average, between 30 and 43% of average daily energy intakes. The older children, especially the girls, who ate out of school at cafes, take-away, or fast-food outlets, chose meals that were low in many nutrients and they failed to compensate for this elsewhere. This particular group of older girls, then, had the diets with the poorest nutritional quality. For comparison with the dietary picture in other countries, the data in Tables 4-6 are taken from a review of some 40 surveys conducted with young people (3). Here, three age ranges are considered, ages lo-18 years. Although there are some differences in the results obtained from these different
DIETAR’y’HABITS DURING ADOLESCENCE
July 1992
Table 4. Average Daily Energy and Nutrient Intakes by Subjects Aged Apgwximately IO-12 Years .-.__- _-.. z_L_Q_._ ..~. __ji- _._i _____..__ Energy Protein
Fat
Carbohydrate
Iron Vitamin C
(MJ)- (g) (g) (a EJ
(g)
(mg)
(mg)
France U.S.A. Australia Finland Canada U.K.
8.3 11.1 9.9 9.9 9.1 8.7
70 106 80 83 79 61
88 106 98 102 87 88
40 36 37 39 36 38
228 340 291 289 273 274
11.3 na 13.8 17.0 12.1 10.0
88 na 79 97 96 49
Females France U.S.A. Australia Finland Canada U.K.
7.4 8.6 8.9 8.2 7.9 7.7
64 77 62 71 70 53
78 82 84 82 77 79
40 36 36 38 37 39
200 269 268 242 234 241
10.4
84 na 96 95 80 49
m
1:9 15.0 10.6 8.6
na, not applicable.
surveys, it should be remembered that different survey methods have been used in different countries, the studies may have been conducted up to a dozen years apart, and the children studied may have been from very different backgrounds. What is surprising, then, is the extent to which the diets of young people in the developed countries of America, Europe, and Australia result in very similar patterns of nutrient intake. Since the late 197Os, the eating habits of adolescents and young adults have fairly consistently resulted in a high proportion of energy from fat. The foods which are most popular are such that decreasing the total food intake, whether because of an attempt to lose weight or for some other reason, tends to increase the level of fat calories because it is the consumption of high carbohydrate foods that is reduced. Results from the lo-12 year old age group show a similar pattern of energy nutrients from all countries, whereas average intakes of selected vitamins were quite variable. For ages J.3-15 years protein, fat, and carbohydrate intakes were all lower for girls than for boys (girls of this age ate less food than boys in this age group). Over the lo-18 year age range, the carbohydrate intakes of boys goes up markedly between lo-12 and 13-15 years and again between 13-15 and 16-18 years. This seen for the girls.
Conclusions Data from other parts of the developed world reinforce the findings of recent studies conducted in
387
Great Britain. The conclusions to emerge from this work are that young people consume diets that are often high in fat and in refined carbohydrate. For the most part their requirements for vitamins and minerals are adequately met, but older girls are prone to low intakes of iron when comparison is made with recommended levels. While there may be concern at the amount of fat in the diet and at the apparently low intakes of energy and of iron by some sections of the adolescent population, the immediate significance of these findings needs to be verified, using biochemical and clinical measurements. Furthermore, the only way to approach an overall change in eating patterns is to look closely at the foods that are eaten by young people. Adolescents are snack eaters (5). Beyond the age of about 12 years they tend not to conform to a regular three-meals-a-day pattern, even while they are still at school. Snack foods should not necessarily be equated with junk food because there is a place for all types of food in a balanced diet-however, by replacing a balanced diet with a succession of high-fat snack foods and confectionery it is probable that some young people are eating “junk diets.” Such eating patterns are probably behind the apparent improvements in intellectual performance brought about by vitamin supplementation (6), and may well reflect a degree of marginal malnutrition among some youngsters who are simply not attaining their potential in school or elsewhere because they are not eating properly* The idea of a balanced diet is not easily marketable Table 5. Average Daily E~rgy and Nutrient Intakes by Subjects Aged Approximately 13-15 Years Carbohydrate
NJ)
(g) (g) (B E)
(9)
Iron Vitamin C (mg) (mg)
Males France U.S.A. Sweden Australia Finland Canada U.K.
10.9 10.7 10.6 9.6 11.8 10.9 10.4
95 97 92 80 101 94 75
291 299 295 292 337 327 324
16.7 17.4 18.7 14.8 21.0 15.0 12.2
88 154 79 68 86 119 49
kmales _trance U.S.A. Sweden Australia Finland Czaada U.K.
8.5 8.0 8.1 8.5 7.6 8.6 7.9
72 97 70 65 63 74 56
222 229 225 249 227 255 240
12.2 12.7 13.9 12.8 13.0 11.3 9.3
72 120 60 65 86 101 48
Energy Protein
Fat
117 40 113 40 103 37 96 38 125 40 105 36 106 38 Yl 85 77 88 73 83 82
40 40 36 39 36 36 39
388
JOURNAL OF ADOLESCENT HEALTH Vol. 13, No. 5
BULL
Table 6. Average Darly Energy and Nutrient Intakes by Subjects Aged Approximately 16-18 Years CarboEnergy Protein
Fat
hydrate
Iron Vitamin C
(g)
(mg) (mg)
32 40 39 39 36 43
330 299 349 351 347 270
lY4 18.6 22.0 16.3 11.0
:; 95 113 114 50
34 40 41 38 36 44
208 229 199 225 235 210
lY7 8.5 13.0 10.3 8.5
na 120 43 89 87 50
WJ)
(g) (8 (%E)
Israel U.S.A. Australia Finland Canada U.K.
10.4 10.7 11.9 12.5 12.3 10.1
82 97 93 110 107 76
93 113 123 130 118 116
Females Israel U.S.A. Australia Finland Canada U.K.
6.7 8.0 7.0 7.7 8.0 7.8
53 74 54 64 68 59
63 85 75 78 76 90
Males
na, not applicable.
and somehow nutrition educators need to find a way of making it more appealing. Fresh fruit and vegetables, foods high in unrefined carbohydrate, need the sort of appeal that advertisers are able to give to the cult characters of television. If turtles with strange names can sell not only clothes and toys but yogurts and pizzas (tasting the same but costing more than their ordinary counterparts), and media hype can get mothers flocking to the chemists for multivitamins in the hope of boosting their children’s intelligence, why cannot those same mothers-who are obviously impressionable when it comes to their children’s health and performance, and persuaded by what their children see and ask for when it comes to the latest craze-be persuaded of the long-term benefits of a balanced diet. For children younger than 9 years of age and for adolescents, too, there needs to be, both in schools and in the home, a system of dietary education which relates food consumption not only to the health and well-being of the individual but which puts the individual’s dietary habits into a global context. In the new climate of “green” awareness, nutrition educators have a new opportunity to reach young people, many of whom arc both knowledgeable and concerned about the environment. If healthy balanced eating is approached from the angle of conservation of resources, minimizing wastage, and preserving the planet there is perhaps
more scope than within the traditional message of “if you continue to eat too much fat and sugar and not enough unrefined carbohydrate, you may one day have a heart attack and you may have poor teeth”-what a negative, uninspiring, often confusing, and apparently contradictory message, nutritionists and health educators have proclaimed. Some progress is being made in trying to interest and motivate young people. Recommendations to eat a balanced diet are being couched in terms of “Look great-get healthy” or “Get healthy-feel great,” appealing to the appearance-conscious among the young women and the sports-conscious among the young men. Young people are much more interested in the immediate effects of what they eat, than in any possible long-term effects on their health and well-being (Howcroft, unpublished observations). This makes the task of educators much more difficult, given the nature of the links between diet and health in affluent countries. The concept of healthy, balanced eating somehow needs to be “packaged” in a way that has lasting appeal. One possible way of approaching this in the current climate of environmental awareness, has been suggested. Before any new dietary educational strategy is planned, it would perhaps be beneficial for those involved in nutrition and health education, together with the producers of snack foods, the caterers, the schoolteachers, the advertisers, and the marketing people to have some sort CAforum for discussing the whole approach to the eating habits of young people.
References ~iI’l%d~fi~~bietary habits of 15 to 25-year-olds. Hum Nutr Appl Nutr 1985. 39:1-68. 2. Department of Health. The Diets of British Schoolchildren, 1989. Report on Health and Social Subjects 36. HMSO. London. 3. Bull NL. Studies of the dietary habits, food consumption and nutrient intakes of adolescents and young adults. World Rev Nutr Diet 1988: 57~24-74. 4. Department ofHealth and Social Security. Diet and Cardiovascular Disease, 1984. Report on Health and Social Subjects 28. HMSO. London. 5. Court JM. Nutrition and adolescents: An overview of concerns in Western society. Med J Austr 1988; 148:S2-7. 6. Schoenthaler SJ, Amos SP, Eysenck HJ, et al. Controlled trial of vitamin-mineral supplementation: effects on intelligence and performance. Pers Indiv Diff 1991; 12~351-62.
CONFERENCE PROCEEDINGS
Dietary Habits, Food Consumption, and Nutrient Intake During Adolescence NICOLA
L. BULL, M.A.,
M-SC.,
M.PHIL.,
Adolescents and young adults adopt eating patterns which may well form the basis of their dietary habits for much of their lives. At the same time, this section of the population can come under considerable pressure from the world at large, to conform to the current trends in fashion, language, behavior, or foods. Recent developments in Western dietary practice have tended to leave adolescents vulnerable to low intakes of energy and of some nutrients, as snacking accounts for an increasing proportion of dietary intake. Achieving a balanced diet is more difficult when the most popuiar and widely available snack foods are high in sugar or in fat. Results from major British studies, together with a review of data from other developed countries, support the need for more effective dietary education for adolescents and for children generally. KEYWORDS: Diet
Nutrient intake Energy intake In 1982 the British Ministry of Agriculture, Fisheries and Food (MAFF) conducted a dietary survey of l525 year olds. This study attempted to look, to a limited extent, at attitudes and habits as well as at food consumption, and the full results were published in 1985 (1). This was followed by a major study of the diets of British schoolchildren, conducted under the supervision of the Department of Health. Analysis of this study was completed in 1989 (2). There are a number of common conclusions from these two studies and they are further reinforced by the work A&~ssreprint requests to: Nicola Bull, M.A., M.Sc., 84 Grove Raad, Tting, He& HP23 5PB, England. TG w was presented at the 5th Congress of the lnternatiomd A.wcidon fir Adolescent Health, iuly 3-6, 1991, Montreux, SWitilWld.
Manuscript aaeptd October 17,
1991.
384
1034-139x/9245.00
Published by
F.R.S.H.
of others who have studied the diets of adolescents throughout the developed world (3).
Results The MAFF study of 15-25 year olds began in 1981 when groups of young people were brought together in various parts of Great Britain for informal discussion sessions concerning their eating habits and attitudes. A number of factors were important in affecting the individual’s food consumption pattern: age (that is, within the band selected for the main survey, which was 15-25 years); living accommodation, especially whether or not the individual was still living at home with his or her parents; social class, which might tend to determine the spending power of the subject and the family meal habits; and also region, the part of the country in which the subject lived. A quota design was used, with market researchers in different parts of the country given a defined set of young people to recruit to the study. In this way the participants were a representative sample (in terms of marital status, educational status, and living accommodation) of British young people aged between 15 and 25 years. A detailed recruitment questionnaire provided a record of the demographic and socioeconomic data, and each subject then completed a preceded 2-week dietary diary. A followup questionnaire included questions about the height and weight and history of pregnancy. The report of this study gives a breakdown of food consumption and details of energy and nutrient intakes against a wide range of variables (1). Table 1 shows the intakes of young people in the three age ranges as percentages of the 1979 United Kingdom recommended daily amounts (RDAs) for energy and
QSociety for Adolescent Medicine, I!%? Elsevier Science Publishing Co., Inc., 6.55 .%vcnue rf the Americas, New York, NY IOOIO
July 1992
DIETARY HABITS DURING ADOLESCENCE
Percentage of Recommended According to Age”
Table 1.
Men (age, yrs) 15-18 19-21 22-25 Energy (%) Iron (%) % energy from fat
84 92 42
86 115 42
85 116 42
Amounts Women (age, yrs) 15-18 19-21 22-25 86 71 43
78 69 43
85 78 45
“Bull 1985.
iron. All other nutrients studied were deemed to be
available in more than sufficient quantities for each of these age/sex groups. Energy intakes were between 80 and 90% adequate on average, suggesting that there were some individuals with very low energy intakes. Iron intakes were markedly lower than recommended levels among the female participants, at between 70 and 80% of RDAs, on average. For rneir and women energy from fat was consistently above 42% on average. The levels were not significantly different for the married subjects. The balance of energy nutrients did not alter in a favorable way when the subject reported being on a diet to lose weight. There still appears to be a preoccupation with carbohydrate-rich foods as “fattening foods” (Table 2). The average energy intakes in these groups over the 2 weeks of the study were quite low, but the percentage of energy from fat remained very high. The older group of weight- and diet-conscious women had decreased the proportion of energy from carbohydrate and increased that from fat. When this diet- and weight-conscious group are looked at further, it can be seen that it contains some of the subjects with very low intakes of both energy and dietary iron compared with the recommended levels for women of their ages (Table 2). It is well known that some young women take weight loss to an extreme and thereby endanger their health or their lives. The following dietary features emerged from the British MAFF study of 15-25 year olds: 1. Consumption of alcoholic drinks increased with age and was higher for men. Almost 40% of
the 15-18 year olds as a whole, said that they drank alcohol between once and three times a week and in the age range 22-25 years, 16% were daily drinkers. 2. Consumption of chocolate and other confectionery showed a tendency to decline with age. 3. Consumption of crisps and similar snacks av-
385
eraged 15 grams per day, but ranged up to 105 grams per day. 4. Average daily consumption of meat and meat products was somewhat higher for men than for women. Chicken was the most popular meat, followed by beefburgers and beef. Meat pies, pork, bacon, and sausages also featured significantly within this category. 5. Vegetable consumption was greater by men than by women and increased with age for both men and women. 6. Average fruit consumption decreased slightly with age and, like the consumption levels of cakes and desserts, appeared to be positively associated with social’class. 7. Consumption of eggs averaged the equivalent of approximately two large eggs per week, and the majority were eaten as fried eggs. 8. Cheese (approximately 90% of it hard cheese) was eaten more by the older groups and averaged 30 grams per day over all subjects. 9. Of the survey participants, 18% reported that they never ate breakfast; only 58% said that they ate breakfast every day. When asked which foods they liked but thought that they should not eat, women produced more answers than men; 26% of the female subjects said chocolate, 18% said chips, and 15% said sweets. (The primary reason given by subjects for listing these foods was that they were fattening.) Of the male subjects, 10% said chocolate, 13% said chips, and 8% said sweets. The women were much more foodconscious than the men; more of them thought that they were overweight, and more of them took an Table 2. Percentage of Recommended Daily Amounts (RDAs) and Nutrient Intake for Women According to Age and Dieting Practice“ Aee
range (vears)
15-18 A Energy (%) Energy (Ml/day) Iron (%) % energy from fat
B
19-21 C
A
B
22-25 C
A
B
C
76 76 74 73 67 66 80 77 80 6.8 6.8 6.6 0.6 6.1 6.0 7.2 6.9 7.2 63 65 62 66 63 58 74 74 73 44 42 43 43 41 43 45 44 46
“Bull 1985.
(A = those subjects who considered themselves to be overweight; B = those subjects who reported being on a diet at the time of the study or who said that they always watched their diet; and C = those subjects who considered that they were overweight and who were also on a diet or watching what they ate.)
386
JOURNAL OF ADOLESCENT HEALTHVol. 13, No. 5
RULL
Table 3. Average Intakes of Energy“
Boys(age,yrs) lo-11 (W/day) % RDA
8.67 91
14-15 10.40 90
Girls (age, yrs) 10-11 7.69 90
14-15 7.85 87
RDA, recommended daily amount. “DOH 1989.
interest in the ingredients of processed foods. Some of the survey subjects were concerned about food additives. A second major British survey was conducted among young people during the early 1980s. This time the focus of attention was schoolchildren and the effects of new school meal arrangements. Two age groups were selected which complement the previous study by covering the younger and preadolescent age group. Boys and girls aged lo-11 years and aged 14-15 years were selected, and the final weighted sample consisted of almost 2700 children who provided 7-day dietary records and whose heights and weights were measured. Again, results have been tabulated in the full published report (2), against a range of demographic variables. included here are some of the main features relating to energy and nutrient intakes and dietary patterns. The average daily energy intake of the 14-15 year old boys was higher than that of the younger boys, and the average energy intakes of boys were higher than those of girls in both age groups (Table 3). Mean energy intakes were about 10% lower than the RDAs, but the children were, on average, on or above the 50th percentile of standards for height and well above the 50th percentile of standards for weight, regardless of energy intake. The average proportion of energy from fat ranged from 37.4 to 38.7% across the different age and sex groups, and three-quarters of the children had intakes of fat which gave a proportion of energy from fat exceeding the 35% recommended by a United Kingdom government panel on diet and cardiovascular disease (4). Milk and chips were fhe two main contributors to these fat intakes. Mean iron intakes of girls were below the RDAs, and older girls also had mean riboflavin intakes below the RDA. Girls, especially the older group, had lower average consumption of milk and breakfast cereals, major sources of this vitamin. Milk and cereals together with bread are also important dietary SXUCES of calcium and again, among the older girls,
some 60% had calcium intakes over the 7 days which were below the RDA. The main sources of energy in the diets of British schoolchildren were bread, chips, milk, biscuits, meat products, cake, and puddings. Almost all children recorded consumption of chips, crisps, cakes, and biscuits. Boys consumed more chips, milk, breakfast cereals, and baked beans. Girls recorded more fruit and fruit juice. Reinforcing the trend emerging from the previous study, fizzy drinks and sweets were more popular among the younger children. The Scottish youngsters recorded higher median consumption of beef, soups, milk, cheese, sausages, chocolates, and sweets and lower median consumption of cakes, biscuits, puddings, potatoes, and vegetables of all kinds, when compared with children in the other regions of Great Britain. Chips and milk were the two major items which varied most with socioeconomic variables. Greater median consumption levels for chips were recorded by children whose fathers were unemployed or whose families received supplementary benefit, and children who had school meals or, in the case of the older group, who ate out of school at cafes, etc., rather than having lunch at home or taking a packed lunch to school. Milk consumption was, on average, lower among these same groups. Although the total average daily intakes of energy and nutrients did not vary with the kind of meal eaten at lunchtimes on weekdays, the dietary patterns of foods consumed, and therefore the dietary sources of energy and nutrients, were to some extent dependent on the provision from school meals. Thus, the older children obtained more than onehalf of the chips they ate during the week from school meals and younger children obtained over one-half the buns and pastries they ate from their school meals. The school meal provided, on average, between 30 and 43% of average daily energy intakes. The older children, especially the girls, who ate out of school at cafes, take-away, or fast-food outlets, chose meals that were low in many nutrients and they failed to compensate for this elsewhere. This particular group of older girls, then, had the diets with the poorest nutritional quality. For comparison with the dietary picture in other countries, the data in Tables 4-6 are taken from a review of some 40 surveys conducted with young people (3). Here, three age ranges are considered, ages lo-18 years. Although there are some differences in the results obtained from these different
DIETAR’y’HABITS DURING ADOLESCENCE
July 1992
Table 4. Average Daily Energy and Nutrient Intakes by Subjects Aged Apgwximately IO-12 Years .-.__- _-.. z_L_Q_._ ..~. __ji- _._i _____..__ Energy Protein
Fat
Carbohydrate
Iron Vitamin C
(MJ)- (g) (g) (a EJ
(g)
(mg)
(mg)
France U.S.A. Australia Finland Canada U.K.
8.3 11.1 9.9 9.9 9.1 8.7
70 106 80 83 79 61
88 106 98 102 87 88
40 36 37 39 36 38
228 340 291 289 273 274
11.3 na 13.8 17.0 12.1 10.0
88 na 79 97 96 49
Females France U.S.A. Australia Finland Canada U.K.
7.4 8.6 8.9 8.2 7.9 7.7
64 77 62 71 70 53
78 82 84 82 77 79
40 36 36 38 37 39
200 269 268 242 234 241
10.4
84 na 96 95 80 49
m
1:9 15.0 10.6 8.6
na, not applicable.
surveys, it should be remembered that different survey methods have been used in different countries, the studies may have been conducted up to a dozen years apart, and the children studied may have been from very different backgrounds. What is surprising, then, is the extent to which the diets of young people in the developed countries of America, Europe, and Australia result in very similar patterns of nutrient intake. Since the late 197Os, the eating habits of adolescents and young adults have fairly consistently resulted in a high proportion of energy from fat. The foods which are most popular are such that decreasing the total food intake, whether because of an attempt to lose weight or for some other reason, tends to increase the level of fat calories because it is the consumption of high carbohydrate foods that is reduced. Results from the lo-12 year old age group show a similar pattern of energy nutrients from all countries, whereas average intakes of selected vitamins were quite variable. For ages J.3-15 years protein, fat, and carbohydrate intakes were all lower for girls than for boys (girls of this age ate less food than boys in this age group). Over the lo-18 year age range, the carbohydrate intakes of boys goes up markedly between lo-12 and 13-15 years and again between 13-15 and 16-18 years. This seen for the girls.
Conclusions Data from other parts of the developed world reinforce the findings of recent studies conducted in
387
Great Britain. The conclusions to emerge from this work are that young people consume diets that are often high in fat and in refined carbohydrate. For the most part their requirements for vitamins and minerals are adequately met, but older girls are prone to low intakes of iron when comparison is made with recommended levels. While there may be concern at the amount of fat in the diet and at the apparently low intakes of energy and of iron by some sections of the adolescent population, the immediate significance of these findings needs to be verified, using biochemical and clinical measurements. Furthermore, the only way to approach an overall change in eating patterns is to look closely at the foods that are eaten by young people. Adolescents are snack eaters (5). Beyond the age of about 12 years they tend not to conform to a regular three-meals-a-day pattern, even while they are still at school. Snack foods should not necessarily be equated with junk food because there is a place for all types of food in a balanced diet-however, by replacing a balanced diet with a succession of high-fat snack foods and confectionery it is probable that some young people are eating “junk diets.” Such eating patterns are probably behind the apparent improvements in intellectual performance brought about by vitamin supplementation (6), and may well reflect a degree of marginal malnutrition among some youngsters who are simply not attaining their potential in school or elsewhere because they are not eating properly* The idea of a balanced diet is not easily marketable Table 5. Average Daily E~rgy and Nutrient Intakes by Subjects Aged Approximately 13-15 Years Carbohydrate
NJ)
(g) (g) (B E)
(9)
Iron Vitamin C (mg) (mg)
Males France U.S.A. Sweden Australia Finland Canada U.K.
10.9 10.7 10.6 9.6 11.8 10.9 10.4
95 97 92 80 101 94 75
291 299 295 292 337 327 324
16.7 17.4 18.7 14.8 21.0 15.0 12.2
88 154 79 68 86 119 49
kmales _trance U.S.A. Sweden Australia Finland Czaada U.K.
8.5 8.0 8.1 8.5 7.6 8.6 7.9
72 97 70 65 63 74 56
222 229 225 249 227 255 240
12.2 12.7 13.9 12.8 13.0 11.3 9.3
72 120 60 65 86 101 48
Energy Protein
Fat
117 40 113 40 103 37 96 38 125 40 105 36 106 38 Yl 85 77 88 73 83 82
40 40 36 39 36 36 39
388
JOURNAL OF ADOLESCENT HEALTH Vol. 13, No. 5
BULL
Table 6. Average Darly Energy and Nutrient Intakes by Subjects Aged Approximately 16-18 Years CarboEnergy Protein
Fat
hydrate
Iron Vitamin C
(g)
(mg) (mg)
32 40 39 39 36 43
330 299 349 351 347 270
lY4 18.6 22.0 16.3 11.0
:; 95 113 114 50
34 40 41 38 36 44
208 229 199 225 235 210
lY7 8.5 13.0 10.3 8.5
na 120 43 89 87 50
WJ)
(g) (8 (%E)
Israel U.S.A. Australia Finland Canada U.K.
10.4 10.7 11.9 12.5 12.3 10.1
82 97 93 110 107 76
93 113 123 130 118 116
Females Israel U.S.A. Australia Finland Canada U.K.
6.7 8.0 7.0 7.7 8.0 7.8
53 74 54 64 68 59
63 85 75 78 76 90
Males
na, not applicable.
and somehow nutrition educators need to find a way of making it more appealing. Fresh fruit and vegetables, foods high in unrefined carbohydrate, need the sort of appeal that advertisers are able to give to the cult characters of television. If turtles with strange names can sell not only clothes and toys but yogurts and pizzas (tasting the same but costing more than their ordinary counterparts), and media hype can get mothers flocking to the chemists for multivitamins in the hope of boosting their children’s intelligence, why cannot those same mothers-who are obviously impressionable when it comes to their children’s health and performance, and persuaded by what their children see and ask for when it comes to the latest craze-be persuaded of the long-term benefits of a balanced diet. For children younger than 9 years of age and for adolescents, too, there needs to be, both in schools and in the home, a system of dietary education which relates food consumption not only to the health and well-being of the individual but which puts the individual’s dietary habits into a global context. In the new climate of “green” awareness, nutrition educators have a new opportunity to reach young people, many of whom arc both knowledgeable and concerned about the environment. If healthy balanced eating is approached from the angle of conservation of resources, minimizing wastage, and preserving the planet there is perhaps
more scope than within the traditional message of “if you continue to eat too much fat and sugar and not enough unrefined carbohydrate, you may one day have a heart attack and you may have poor teeth”-what a negative, uninspiring, often confusing, and apparently contradictory message, nutritionists and health educators have proclaimed. Some progress is being made in trying to interest and motivate young people. Recommendations to eat a balanced diet are being couched in terms of “Look great-get healthy” or “Get healthy-feel great,” appealing to the appearance-conscious among the young women and the sports-conscious among the young men. Young people are much more interested in the immediate effects of what they eat, than in any possible long-term effects on their health and well-being (Howcroft, unpublished observations). This makes the task of educators much more difficult, given the nature of the links between diet and health in affluent countries. The concept of healthy, balanced eating somehow needs to be “packaged” in a way that has lasting appeal. One possible way of approaching this in the current climate of environmental awareness, has been suggested. Before any new dietary educational strategy is planned, it would perhaps be beneficial for those involved in nutrition and health education, together with the producers of snack foods, the caterers, the schoolteachers, the advertisers, and the marketing people to have some sort CAforum for discussing the whole approach to the eating habits of young people.
References ~iI’l%d~fi~~bietary habits of 15 to 25-year-olds. Hum Nutr Appl Nutr 1985. 39:1-68. 2. Department of Health. The Diets of British Schoolchildren, 1989. Report on Health and Social Subjects 36. HMSO. London. 3. Bull NL. Studies of the dietary habits, food consumption and nutrient intakes of adolescents and young adults. World Rev Nutr Diet 1988: 57~24-74. 4. Department ofHealth and Social Security. Diet and Cardiovascular Disease, 1984. Report on Health and Social Subjects 28. HMSO. London. 5. Court JM. Nutrition and adolescents: An overview of concerns in Western society. Med J Austr 1988; 148:S2-7. 6. Schoenthaler SJ, Amos SP, Eysenck HJ, et al. Controlled trial of vitamin-mineral supplementation: effects on intelligence and performance. Pers Indiv Diff 1991; 12~351-62.
