Intake of Very-Long-Chain N-3 Fatty Acids Related to Social Status and Lifestyle

Intake of very-long-chain n-3 fatty acids related to social status and lifestyle

LRK Johansson1, K Solvoll2, G-E Aa Bjùrneboe1 and CA Drevon1

1National Nutrition Council, Norway; and 2Institute for Nutrition Research, University of Oslo, Norway

Objectives: Little information is available about the intake of very-long-chain n-3 fatty acids in random samples of populations. We examined if the intake of these fatty acids was associated with gender, social status and lifestyle in a similar way as other indicators for a healthy diet in a nationwide survey. Design and subjects: Data were obtained from self-administered quantitative food frequency questionnaires ®lled in by a representative sample of Norwegian men and women, aged 16 ± 79 y. 3144 (63%) of the invited subjects responded with acceptable questionnaires. Results: Daily intake of very-long-chain n-3 fatty acids was on average 0.9 g=d and 0.4% of total energy was derived from these fatty acids. Energy derived from very-long-chain n-3 fatty acids was slightly higher among men than women, and two-fold higher among subjects aged 60 ± 79 vs 16 ± 29 y. White collar workers had higher intake of very-long-chain n-3 fatty acids than blue collar workers. Men and women in the highest quartile of intake of very-long-chain n-3 fatty acids had 2 ± 3 E% higher fat intake (mostly mono- and polyunsaturated fatty acids), as compared to individuals in the lowest quartile. They also had 3 ± 4 fold higher daily intake of retinol and vitamin D, as well as 20 ± 50% higher intake of fruits and vegetables, dietary ®bre and vitamin C. Conclusions: Intake of very-long-chain n-3 fatty acids was correlated to indicators for healthy dietary habits. However, contrary to many other indicators of a healthy diet, energy derived from very-long-chain n-3 fatty acids was not signi®cantly associated with female gender or non-smoking. Sponsorship: Ministry for Health and Social Affairs, Ministry for Agriculture and Norwegian Research Council. Descriptors: very-long-chain n-3 fatty acids; ®sh; cod liver oil; social status; lifestyle

Introduction 1989). In the other intervention study a dietary change to a Mediterranean alpha-linolenic acid-rich diet was asso- Very-long-chain n-3 fatty acids are biologically important ciated with a 70% reduction of total mortality, providing nutrients (Drevon, 1992). The main sources for these fatty 0.6 g=d of alpha-linolenic acid in the control group and acids are marine oils and ®sh. In some studies the intake of 2g=d in the intervention group (de Lorgeril et al, 1994). As marine oils (Nestel, 1987) and ®sh (Kromhout et al, 1985; conversion of alpha-linolenic acid to eicosapentaenoic acid Daviglus et al, 1997) are associated with reduced risk for (EPA) occurs in humans, increased intake of alpha-linole- coronary heart disease (CHD), although this has not been nic acid may have effects similar to those of very long- observed in other studies (Vollset et al, 1985; Morris et al, chain n-3 fatty acids from ®sh (McKeigue, 1994). Thus, 1995; Ascherio et al, 1995). Of four prospective studies these observations suggest that bioavailable very-long- reporting intake of n-3 fatty acids from ®sh, one found an chain n-3 fatty acids may be important for prevention of inverse association (Dolecek, 1992), another reported a CHD. positive association (Pietinen et al, 1997) and the others The intake of very-long-chain n-3 fatty acids is reported no signi®cant association to CHD (Morris et al, described in clinical trials (Bùnaa et al, 1990; Sùyland et 1995; Ascherio et al, 1995). In two randomised clinical al, 1993; Sùyland et al, 1994; Brude et al, 1997), selected trials increased intake of ®sh (Burr et al, 1989) and alpha- groups (Bang et al, 1980; Tjùnneland et al, 1993; Nydahl et linolenic acid (C 18:3, n-3) (de Lorgeril et al, 1994) al, 1996; Hjartaker et al, 1997) and prospective studies reduced the mortality among patients who had recovered (Morris et al, 1995; Ascherio et al, 1995; Dolecek, 1992; from myocardial infarction, without signi®cantly affecting Pietinen et al, 1997), but little information is available serum cholesterol concentration. In the DART trial advice about the intake of very-long-chain n-3 fatty acids in to eat at least two weekly portions of fatty ®sh was random samples of populations (Steingrimsdottir et al, associated with a 29% reduction of total mortality in the 1995). We therefore assessed the intake and sources of ®rst two years after myocardial infarction (Burr et al, very-long-chain n-3 fatty acids and related the intake to socio-demographic and life-style variables in a national dietary survey. Healthy lifestyle is associated with high social status (Blaxter, 1990; PraÈttaÈlaÈ et al, 1994) and Correspondence: Lars RK Johansson, National Nutrition Council, Box women usually have more healthy diets than men (Klee- 8139 Dep., N-0033 Oslo, Norway. Received February 26 1998; revised June 11 1998; accepted June mola et al, 1994; Johansson et al, 1997a). In the present 13 1998 study we tested the following hypotheses: Intake of very-long-chain n-3 fatty acids LRK Johansson et al 717 1. Women have higher intake of very-long-chain n-3 fatty Daily intake of energy and nutrients was computed using acids than men. the 1995 version of the Norwegian food composition table 2. High social status is associated to higher intake of very- and software systems developed at Institute for Nutrition long-chain n-3 fatty acids than low social status. Research. The calculated intake of energy and nutrients in 3. Subjects with healthy lifestyle (for example regular the present analysis differs slightly from earlier published physical exercise and non-smoking) have higher intake results from this survey, since the conversion factor for of very-long-chain n-3 fatty acids than those without energy derived from fat was changed from 38 ± 37 kJ=g, and these habits. dietary ®bre was not included in the carbohydrates in the 4. High intake of very-long-chain n-3 fatty acids is asso- 1995 as compared to the 1991 version of the food composi- ciated with indicators of a healthy diet. tion table. Total intake of very-long-chain n-3 fatty acids was computed as the sum of eicosapentaenoic acid (EPA) Methods (20:5, n-3), docosapentaenoic acid (DPA) (22:5, n-3) and docosahexaenoic acid (DHA) (22:6, n-3). Intake of very- Subjects long-chain n-3 fatty acids reported by the questionnaire has previously been evaluated against the concentration of In a national dietary survey (NORKOST), a self-adminis- plasma phospholipids among 579 men and women (Frost tered quantitative food frequency questionnaire was ®lled Andersen et al, 1996). Correlation coef®cients between in by a representative random sample of Norwegians aged plasma content and dietary intake of fatty acids were 0.55 16 ± 79 y; 3144 subjects (63%) completed the questionnaire. and 0.56 for EPA and DHA, respectively, when intake and The distribution of subjects in different groups of socio- plasma concentration were expressed as percent of total economic status, location of residence and level of educa- fatty acids. Other nutrients reported by the questionnaire tion was similar among our participants as compared to the were evaluated against 14 d dietary records among 38 general population (Statistics Norway, 1995). Moreover, elderly women (Nes et al, 1992) and against 48 h recall there were only small differences between responders and among 123 dermatologic outpatients (Solvoll et al, 1993). the total random sample regarding age, sex, geographical These studies showed an acceptable accuracy of the ques- distribution and educational level (Johansson et al, 1997a). tionnaire in assessing individual intakes of a wide range of nutrients, including very-long-chain n-3 fatty acids. Questionnaire The questionnaire was designed to cover the whole diet. It Statistics included about 180 food items and the frequency of con- Intake of very-long-chain n-3 fatty acids was skewed and sumption was given per day, per week or per month therefore non-parametric statistical methods were chosen depending on the food item. The portion sizes were for analysis. Differences between two or more groups were quanti®ed as slices, glasses, cups, pieces, decilitres and tested with Mann ± Whitney U test and Kruskal ± Wallis H spoons and converted to weights on the basis of standard test, respectively. Spearman rank correlations were used to portions (Blaker & Aarsland, 1989). Questions about test the association between the intake of very-long-chain weight, height, physical activity, smoking habits, meal n-3 fatty acids, ®sh and cod liver oil. Chi square test was frequency and personal attitudes related to diet and body used to test differences in proportion between subgroups of weight, were also included in the form. Statistics Norway participants. Data were analysed using the program SPSS provided information about the subjects' level of education (SPSS, 1996). and several other demographic and geographical variables from their registers. Occupation was classi®ed as blue collar workers (unskilled and skilled workers, and lower Results level salaried employees) and white collar workers (mean and higher level salaried employees) (Central Bureau of Intake and sources for very-long-chain n-3 fatty acids Statistics, 1984). Smoking habits were classi®ed as non- Fish and cod liver oil contributed with 56% and 33%, smokers or smokers of cigarettes or pipes. Frequency of respectively, of the total intake of very-long-chain n-3 fatty exercise was evaluated by the question: How often do you acids (Table 1). The distribution of the intake of very-long- have physical exercise for at least 20 min (walking, jog- chain n-3 fatty acids was skewed and the range for intake ging, bicycling or swimming)? (Never, < 1, 1, 2 ± 3, 4 ± 6 was large. For all subjects mean and median daily intake of times=week or daily). Attention to healthy diet was deter- very-long-chain n-3 fatty acids was 0.89 and 0.59 g=d, mined by the question: What attention do you pay to keeping a healthy diet? (very low, low, medium, high or Table 1 Dietary sources of very-long-chain fatty acids, % of total intake, very high). A more detailed description of the participants, and absolute daily intake; means (s.d.) the questionnaire, the calculation of nutrients and reported EPAa DPAb DHAc Sum of EPA, dietary habits, is given in recent publications (Johansson et 20:5 22:5 22:6 DPA, DHA al, 1997a,b). The questionnaire included questions about the fre- Cod liver oil (%) 39 14 32 33 Fish oil (%) 3 Ð 2 2 quency for use and portion size of cod liver oil, cod liver Fish (%) 55 43 57 56 oil capsules and ®sh oil capsules. Use of cod liver oil has Meat (%) 3 43 4 6 traditionally been recommended during the dark period of Other foods (%) Ð Ð 4 2 the year in Norway. Therefore, questions about use of cod Total (%) 100 100 99 99 liver oil was differentiated between the whole year and the Intake (g=d) 0.33 (0.40) 0.07 (0.05) 0.49 (0.51) 0.89 (0.95) winter season only. Reported frequency for use during the aEPA eicosapentaenoic acid; bDPA docosapentaenoic acid; winter was divided by a factor of two. cDHA docosahexaenoic acid. Intake of very-long-chain n-3 fatty acids LRK Johansson et al 718 respectively, and mean and median dietary content was 10 MJ, men no longer had higher intake of ®sh and cod 0.36 and 0.24 E%, respectively. Mean intake of ®sh was liver oil than women. The fraction of male users of cod 67 g=d. Less than 2% of the population reported no intake liver oil was similar to female users (37% vs 34%). A larger of ®sh and 6% had an intake below 10 g=d. Cod liver oil fraction of men reported having the largest portion size of was never used by 65% of the subjects, whereas 19% used cod liver oil (one table spoon=time) as compared to women it during the whole year, and only during the winter season (76% vs 58%). The mean frequency for use of cod liver oil by an additionally 16%. Mean intake of cod liver oil was was 3.7 times=week among users of cod liver oil. 1.3 g=d. Ten percent of the participants had a cod liver oil The percent of dietary energy derived from very-long- intake of 1 ± 4 g=d and an additional 10% had at least 5 g=d. chain n-3 fatty acids, as well as the intake of ®sh and cod Fish oil supplements were never used by 96% of the liver oil, was higher in the older compared to the younger subjects. age groups (Figures 1, 2, 3). Subjects aged 60 ± 79 y had Spearman correlation coef®cients between intake of two-fold higher intake of very-long-chain n-3 fatty acids, very-long-chain n-3 fatty acids vs ®sh intake and vs ®sh and cod liver oil than subjects aged 16 ± 29 y. intake of cod liver oil were 0.61 and 0.57, respectively, and 0.17 between intake of ®sh vs cod liver oil (P < 0.001). Characteristics of subjects with low vs high intake of very- Information about intake of cod liver oil and ®sh was most long-chain n-3 fatty acids important to classify subjects into quartiles of intake of Men and women in the highest quartile of intake of very- very-long-chain n-3 fatty acids. Half of the subjects report- long-chain n-3 fatty acids had 10 times higher intake of ing use of cod liver oil had an intake of very-long-chain n-3 fatty acids within the range of the highest quartile and 8% within the lowest. Among subjects reporting use of cod liver oil and belonging to the highest quartile of ®sh intake, 72% had an intake of very-long-chain n-3 fatty acids within the range of the highest and < 1% had an intake within the lowest quartile of intake.

Intake of very-long-chain n-3 fatty acids related to gender and age Daily intake of very-long-chain n-3 fatty acids, as well as other polyunsaturated fatty acids, was higher among men compared to women (Table 2). The percent of total dietary energy (E%) from very-long-chain n-3 fatty acids was slightly, but signi®cantly higher among men than women. Men also had higher daily intake of ®sh and cod liver oil than women. However, when intake was computed per

Table 2 Daily intake of energy, fatty acids, ®sh and cod liver oil, and frequency for use of cod liver oil (times=week) among men (1517) and women (1627); means (s.d.)

Men Women P-valuea Figure 1 Percent of total dietary energy derived from very-long-chain n-3 fatty acids (sum of 20:5, 22:5, 22:6) related to age groups among men Energy (MJ=d) 11.3 (4.1) 8.0 (2.8) < 0.001 (s) and women (d); means and 95% con®dence intervals.

Fat (g=d) 97.4 (44.4) 67.0 (29.1) < 0.001 Fatty acids (g=d) Linoleic acid 18:2 n-6 13.5 (8.5) 8.8 (5.1) < 0.001 Aracidonic acid 20:4 n-6 0.17 (0.08) 0.12 (0.05) < 0.001 Linolenic acid 18:3 n-3 1.8 (1.2) 1.2 (0.7) < 0.001 EPA 20:5 n-3 0.41 (0.46) 0.27 (0.31) < 0.001 DPA 22:5 n-3 0.08 (0.06) 0.06 (0.04) < 0.001 DHA 22:6 n-3 0.59 (0.59) 0.40 (0.40) < 0.001 EPA, DPA, DHA, total 1.08 (1.1) 0.72 (0.75) < 0.001 Ratio n-3=n-6 0.23 (0.13) 0.24 (0.14) 0.267

Percent of energy (%) Fat 31.5 (5.8) 30.6 (5.9) < 0.001 SFA 12.3 (2.8) 12.2 (2.7) 0.597 MUFA 11.1 (2.2) 10.7 (2.2) < 0.001 PUFA 5.7 (1.9) 5.3 (1.8) < 0.001 EPA, DPA, DHA, total 0.37 (0.39) 0.35 (0.37) 0.046

Fish (g=d) 78.(62) 57.(40) < 0.001 Fish (g=10 MJ) 73.(55) 75.(52) 0.047 Cod liver oil (g=d) 1.4 (3.0) 1.1 (2.6) 0.028 Cod liver oil (g=10 MJ) 1.4 (3.1) 1.5 (3.7) 0.152 Cod liver oil (times=week) 1.3 (2.2) 1.3 (2.2) 0.198

SFA saturated f.a.; MUFA monounsaturated f.a.; PUFA polyunsaturated f.a. Figure 2 Intake of ®sh (g=10 MJ) related to age groups among men (s) aMann ± Whitney U-test was used to test differences between genders. and women (d); means and 95% con®dence intervals. Intake of very-long-chain n-3 fatty acids LRK Johansson et al 719 acids. More of both men and women in the highest quartile of intake reported high attention to healthy diet as compared to the lowest quartile. The percent of subjects with short education, blue collar workers and subjects with less physical leisure exercise than once weekly, was lower in the highest as compared to the lowest quartile for intake among men, but not among women.

Intake related to social status and lifestyle Dietary energy derived from very-long-chain n-3 fatty acids was higher among white vs blue collar workers, as well as among subjects paying high vs low attention to keeping a healthy diet (Table 4). Length of education and regular physical leisure exercise was associated with a higher intake of very-long-chain n-3 fatty acids only among men. Smoking habits were not signi®cantly associated with dietary intake of very-long-chain n-3 fatty acids in either gender. The dietary intake of very-long-chain n-3 fatty acids did not differ signi®cantly between the six main Figure 3 Intake of cod liver oil (g=10 MJ) related to age groups among men (s) and women (d); means and 95% con®dence intervals. geographical regions of Norway or between rural and urban areas. Fish intake was signi®cantly lower among subjects reporting low as compared to high attention paid to healthy very-long-chain n-3 fatty acids than subjects in the lowest diet, among men (73 vs 88 g=d) as well as for women (53 vs quartile (Table 3). They had 2 ± 3 E% higher fat intake, due 62 g=d). Fish intake was also signi®cantly lower among to mono- and polyunsaturated fatty acids. Men and women male blue vs white collar workers (74 vs 80 g=d), for men in the highest quartile of intake of very-long-chain n-3 fatty with < 13 vs 13 y of education (78 vs 82 g=d), and acids also had 3-4 fold higher daily intake of retinol and among males with regular physical leisure activity < 1 vitamin D, as well as 20 ± 50% higher intake of fruits and vs 1 time=week (71 vs 80 g=d), which was not observed vegetables, dietary ®bre and vitamin C. Furthermore, they among women. used vitamin supplements more frequently. Even if they For both genders the intake of cod liver oil was sig- were 9 ± 10 y older, they had higher energy intake, and the ni®cantly lower among blue than white collar workers, for body mass index (BMI) was not different from subjects in subjects with short vs long education, among subjects with the lowest quartile for intake of very-long-chain n-3 fatty physical leisure activity < 1 weekly as compared to 1

Table 3 Dietary intake and characteristics among men and women with low (quartile 1) and high (quartile 4) daily intake of very-long-chain n-3 fatty acids; means (s.d.)

Men Women

Quartile 1 Quartile 4 Quartile 1 Quartile 4 (n 379) (n 378) (n 406) (n 406)

Dietary intake Energy (MJ=d) 10.3 (3.7) 12.2 (4.6)*** 7.2 (3.0) 8.5 (2.6)*** Fat (E%) 29.7 (6.0) 32.4 (5.7)*** 28.6 (6.1) 32.2 (5.9)** SFA (E%) 12.2 (3.0) 12.0 (2.8) ns 12.1 (3.0) 12.2 (2.6) ns MUFA (E%) 10.4 (2.2) 11.6 (2.1)*** 9.9 (2.3) 11.4 (2.1)*** PUFA (E%) 5.0 (1.7) 6.2 (1.7)*** 4.6 (1.6) 5.9 (1.8)*** EPA, DPA, DHA, total (E%) 0.08 (0.04) 0.86 (0.47)*** 0.07 (0.04) 0.82 (0.46)*** EPA, DPA, DHA, total (g=d) 0.19 (0.08) 2.57 (1.22)*** 0.13 (0.06) 1.73 (0.84)***

Retinol (mg=d) 0.93 (0.60) 2.59 (2.08)*** 0.73 (0.56) 2.00 (1.24)*** Vitamin D (mg=d) 5.1 (4.4) 23.5 (12.6)*** 5.3 (6.3) 18.5 (11.9)*** Vitamin C (mg=d) 121 (70) 171 (101)*** 124 (76) 162 (83)*** Fibre (g=d) 23 (9) 29 (10)*** 19 (8) 23 (8)***

Fish (g=d) 33 (27) 125 (83)*** 29 (23) 81 (51)*** Cod liver oil (g=d) 0.03 (0.1) 5.0 (4.2)*** 0.02 (0.08) 4.1 (3.9)*** Fruit and vegetables (g=d) 250 (197) 376 (263)*** 273 (196) 367 (237)*** Vitamin supplements (times=week) 1.9 (3.4) 2.8 (4.5)* 3.1 (4.2) 3.9 (4.4)*

Age (y) 37.5 (16.5) 47.8 (15.8)*** 37.8 (17.0) 46.9 (16.6)*** Body mass index (weight=height2) 24.3 (3.2) 24.4 (2.7) ns 23.1 (3.9) 23.4 (3.8) ns Education 13 y (%) 14 25*** 19 22 ns Blue collar workers (%) 33 26* 24 21 ns High attention to healthy diet (%) 20 40*** 30 49*** Exercise < 1 time=week (%) 36 21*** 24 20 ns Non-smokers (%) 62 62 ns 63 65 ns

*P < 0.05; **P < 0.01; ***P < 0.001 for differences between quartile 1 and 4 within gender. Mann ± Whitney U was used to test difference in dietary intake and characteristics, and w2 test to test difference in proportions. Intake of very-long-chain n-3 fatty acids LRK Johansson et al 720 Table 4 Dietary energy from very-long-chain n-3 fatty acids (E%) related to social and lifestyle variables among men and women; means (s.d.)

Number Men Pa Number Women Pa

Occupation blue collar worker 404 0.32 (0.33) 370 0.30 (0.30) white collar worker 457 0.41 (0.41) < 0.001 459 0.36 (0.39) 0.048 Education < 13 y 1139 0.37 (0.39) 1224 0.35 (0.37) 13 y 307 0.43 (0.39) < 0.001 316 0.37 (0.40) 0.730 Attention to healthy diet very low, low and medium 1086 0.32 (0.34) 993 0.30 (0.31) high and very high 428 0.50 (0.48) < 0.001 630 0.43 (0.43) < 0.001 Physical leisure exercise < 1 time=week 441 0.31 (0.31) 367 0.32 (0.34) 1 time=week 1067 0.40 (0.41) < 0.001 1247 0.36 (0.38) 0.118 Smoking habits non-smoker 926 0.39 (0.40) 1040 0.36 (0.38) smoker 591 0.36 (0.37) 0.275 587 0.34 (0.37) 0.587

aMann ± Whitney U-test was used to evaluate differences between subgroups within genders.

weekly, and for subjects reporting low vs high attention to (0.34 g=d) was higher than earlier reported from inland healthy diet. Furthermore, male smokers had a lower intake districts of Northern Norway (0.25 g=d), but lower than of cod liver oil compared to non-smokers. reported (0.9 g=d) from coastal districts (Simonsen et al, 1988). The average intake of ®sh in the present study (67 g=d) Discussion was higher than in Norwegian household consumption Our analysis started with the assumption that intake of surveys and market surveys (National Nutrition Council, very-long-chain n-3 fatty acids would be associated with 1996). Validation studies have shown that the intake of ®sh gender, social status and lifestyle similar to many other was higher when reported with the questionnaire than with indicators for healthy dietary choices (Blaxter, 1990; PraÈt- dietary records (108 vs 75 g=d) (Nes et al, 1992) and 48 h taÈlaÈ et al, 1994; Kleemola et al, 1994). However, the recall (71 vs 64 g=d) (Solvoll et al, 1993). The ®sh intake in present study showed that the percent of total dietary our survey was higher than reported in national dietary energy from very-long-chain n-3 fatty acids was slightly, surveys in the Netherlands (approximately 10 g=d) (Hul- but signi®cantly higher among men than women. High shof et al, 1991), Denmark (24 g=d) (Andersen et al, 1996), dietary content of very-long-chain n-3 fatty acids was Sweden (30 g=d) (Becker, 1994), as well as in large pro- correlated to length of education and regular leisure exer- spective surveys in the Netherlands (Kromhout et al, 1985) cise among men, but not among women. Furthermore, the and USA (Daviglus et al, 1997), and secondary prevention intake of these fatty acids was not signi®cantly correlated to trials in UK (Burr et al, 1989). However, the ®sh intake was smoking habits, in contrast to other indicators for a healthy lower than reported in national surveys in Iceland (73 g=d) diet (Johansson et al, 1997a; Margetts & Jackson, 1993; and Japan (approximately 90 g=d) (World Health Organiza- JaÈrvinen et al, 1994). Degree of attention paid to keeping a tion, 1990). We have not enough data about the Norwegian healthy diet was strongly associated with the intake of very- ®sh consumption to tell if it has changed during the last long-chain n-3 fatty acids in both genders, as expected. decades (National Nutrition Council, 1996). Subjects in the highest quartile of intake of these fatty acids The percentage of consumers of cod liver oil was higher also had a much higher intake of other healthy foods, such in the present study than in earlier Norwegian dietary as fruits and vegetables. surveys (Johansson, 1993) and the average daily intake of Intake of ®sh and cod liver oil was strong determinants cod liver oil was higher than the total Norwegian produc- for the intake of very-long-chain n-3 fatty acids. Fish intake tion of cod liver oil (approximately 0.3 g=d=inhabitant) in was positively correlated to high social status among men, the 1980s and early 1990s (Johansson, 1993). Marketing of but not among women. The use of cod liver oil only marine oils has been extensive and it is likely that the differed slightly between men and women, in contrast to intake of cod liver oil has increased in Norway during the use of vitamin supplements, which were used more often 1990s. However, the average intake of cod liver oil in our among women than men in the present survey (58 vs 48%) study was less than half reported by Icelanders (3 g=d) (Johansson et al, 1997a), indicating that women prefer non- (Steingrimsdottir et al, 1995). It was also much lower than fatty in front of fatty supplements. This may have caused found among Norwegian families during the war 1942 ± the weaker association between intake of very-long-chain 1945 when the intake of cod liver oil and ®sh was 4 g=d n-3 fatty acids and social status among women than men. and 285 g=d, respectively (Strùm, 1948). The total intake of linolenic acid and very-long-chain n- 3 fatty acids reported in the present survey was 0.9 E%, and Conclusions above the recommended minimum level of 0.5 E% (Nordic nutrition recommendations, 1996). The intake of very-long- In summary, the range of energy derived from very-long- chain n-3 fatty acids was higher than found among Danes chain n-3 fatty acids was very large in the population (Bang et al, 1980; Tjùnneland et al, 1993), Swedes (Nydahl studied. Men had slightly higher intake of these fatty et al, 1996) and US health professionals (Ascherio et al, acids compared to women. High intake of very-long- 1995), and lower than among Icelanders (Steingrimsdottir chain n-3 fatty acids was associated with high social et al, 1995). The intake of EPA in the present study status and regular physical leisure exercise among men. Intake of very-long-chain n-3 fatty acids LRK Johansson et al 721 In both genders intake of very-long-chain n-3 fatty acids Johansson L (1993). Kostholdets betydning for dùdeligheten av hjertein- was correlated to other indicators for a healthy diet, except farkt i Norge de siste 100aÊr (In Norwegian). 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