Infant feeding practices and associated factors in the first six months of life: the Norwegian infant nutrition survey.

AIM: To describe and evaluate infant feeding practices during the first 6 mo of life in relation to recommendations, and to study infant feeding practices in relation to maternal and infant characteristics. METHODS: Data from 2383 Norwegian infants aged 6 mo were collected by a self-administered semi-quantitative food-frequency questionnaire measuring feeding practices at 6 mo and feeding practices retrospectively at < or = 5.5 mo of age. RESULTS: Only 1% of the infants had never been breastfed. The proportion of breastfed infants was 96% at 1 mo, 85% at 4 mo and 80% at 6 mo. The proportion of exclusively breastfed infants was 90% at 1 mo, 44% at 4 mo and 7% at 6 mo. Twenty-one percent of the infants were introduced to solid foods before the age of 4 mo. For exclusive breastfeeding at 4 mo, breastfeeding at 6 mo and timely introduction of solid foods (not before 4 mo) significant positive trends were found for maternal age, education and degree of urbanization. Negative associations were found for maternal smoking. Furthermore, exclusive breastfeeding at 4 mo was associated with infant gender and marital status, and the odds of breastfeeding at 6 mo significantly decreased with decreasing infant birthweight. Finally, both the odds of exclusive breastfeeding at 4 mo and of breastfeeding at 6 mo increased with increasing numbers of children. CONCLUSION: These results indicate that a majority of Norwegian infants are fed in accordance with infant feeding recommendations during their first 6mo of life. However, the duration of exclusive breastfeeding is shorter than recommended. Infant feeding practices are significantly associated with maternal and infant characteristics.

Healthy dietary habits in relation to social determinants and lifestyle factors.

The aim of the present study was to evaluate the importance of social status and lifestyle for dietary habits, since these factors may influence life expectancy. We studied the association of four indicators for healthy dietary habits (fruits and vegetables, fibre, fat and Hegsted score) with sex, age, socio-economic status, education, physical leisure exercise, smoking and personal attention paid to keeping a healthy diet. Data were gathered with a self-administered quantitative food-frequency questionnaire distributed to a representative sample of Norwegian men and women aged 16-79 years in a national dietary survey, of whom 3144 subjects (63%) responded. Age and female sex were positively associated with indicators for healthy dietary habits. By separate evaluation length of education, regular physical leisure exercise and degree of attention paid to keeping a healthy diet were positively associated with all four indicators for healthy dietary habits in both sexes. Socio-economic status, location of residence and smoking habits were associated with from one to three indicators for healthy dietary habits. In a multiple regression model, age, education and location of residence together explained from 1 to 9% of the variation (R2) in the four dietary indicators. Length of education was significantly associated with three of four dietary indicators both among men and women. By including the variable 'attention paid to keeping a healthy diet' in the model, R2 increased to between 4 and 15% for the four dietary indicators. Length of education remained correlated to three dietary indicators among women, and one indicator among men, after adjusting for attention to healthy diet, age and location of residence. Residence in cities remained correlated to two indicators among men, but none among women, after adjusting for age, education and attention to healthy diet. In conclusion, education was associated with indicators of a healthy diet. Attention to healthy diet showed the strongest and most consistent association with all four indicators for healthy dietary habits in both sexes. This suggests that personal preferences may be just as important for having a healthy diet as social status determinants.

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

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 filled 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 fibre 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 significantly associated with female gender or non-smoking.

[Measures to promote healthy dietary habits among schoolchildren]. / Tiltak for å fremme sunne kostvaner blant skoleelever.

The Norwegian National Nutrition Council has, over the past years, implemented a number of measures designed specifically to promote well-organized school meals and increase the consumption of fruit and vegetables among school children. These measures include the development of national guidelines for organizing school meals, economic support for trying out new methods of operating a school cafeteria, national campaigns to promote the traditional Norwegian packed lunch, open community meetings with political and administrative leaders at municipality level, the introduction of a system whereby pupils can purchase fresh fruit and vegetables at school, and advocacy through mass media. Results of an ongoing evaluation seem to indicate that these measures have had a positive effect on the organization of school meals. More young children are attended to by an adult during mealtimes, more pupils are allowed at least 20 minutes for their lunch break, and a growing number of secondary schools are introducing school cafeterias. However, only half of the total number of schools seem to be aware of the new guidelines, and much more work is required in order to ensure all students are provided with a well-organized school meal. Health personnel play a critical role in ensuring that this work is given political priority, also at the local level.

Under- and overreporting of energy intake related to weight status and lifestyle in a nationwide sample.

Desire for weight change and level of dietary consciousness may severely bias reported food intake in dietary surveys. We evaluated to what degree under- and overreporting of energy intake (EI) was related to lifestyle, sociodemographic variables, and attitudes about body weight and diet in a nationwide dietary survey. Data were gathered by a self-administered quantitative food-frequency questionnaire distributed to a representative sample of men and women aged 16-79 y in Norway, of whom 3144 subjects (63%) responded. Reported EI was related to estimated basal metabolic rate (BMR) based on self-reported body weight, age, and sex. An EI:BMR < 1.35 was considered to represent underreporting and an EI:BMR > or = 2.4 as overreporting of EI. Fewer men than women underreported EI (38% compared with 45%). The fraction of overreporters did not differ significantly between sexes (7% of the men compared with 5% of the women). A large proportion of underreporters was obese (9%) and wanted to reduce their weight (41%). Few overreporters were obese and 12% wanted to increase their weight. Underreporters consumed fewer foods rich in fat and sugar than did the other subjects. Multiple regression analysis showed that desire for weight change and physical activity score were significantly correlated with both EI and EI:BMR when adjusted for sociodemographic and lifestyle variables. Our findings indicated that attitudes about one's own body weight influenced reported EI. These attitudes are important in the interpretation of dietary data because many of the subjects (> 30%) wanted to change their body weight.

Response rates with different distribution methods and reward, and reproducibility of a quantitative food frequency questionnaire.

OBJECTIVES: To evaluate the use of a self-administered quantitative food frequency questionnaire (QFFQ) in a national dietary survey concerning (a) response rates with different distribution methods and reward; (b) degree of underreporting of energy intake; (c) reproducibility of the QFFQ; and (d) seasonal variation on reported intake. DESIGN AND SUBJECTS: A pilot study was performed in 1992 to test response rates to the QFFQ with three different distribution methods, with and without reward, in a random sample of 1200 adults aged 16-79 y. In another study, the QFFQ was distributed to a nation-wide, representative random sample of 5008 adults aged 16-79 y during June, September, November 1993 and March 1994. Reproducibility was evaluated among 90 responders to the survey who answered another QFFQ six weeks later. RESULTS: The distribution method combining postal distribution and collecting the QFFQ by interviewer as well as an offer to participate in a lottery, gave the highest response rate (72%). The possibility to get a reward increased the response rate by 9, 14 and 57%, respectively, depending on the distribution method used. The mean daily energy intake and the percentage of subjects claiming to have unlikely low energy intake did not differ significantly between the different ways of distribution. In the main survey the mean ratio between energy intake and estimated basal metabolic rate was 1.58 among men and 1.47 among women, and 37% of men and 45% of women had a ratio below 1.35. Spearman rank correlations between the two QFFQ ranged from 0.48 (edible fats) to 0.91 (coffee) with a median coefficient of 0.70. For nutrients correlations ranged from 0.55 (carbohydrate E%) to 0.81 (alcohol), with a median coefficient of 0.72. The season of questionnaire administration was of minor importance for the reported intake of the main foods and nutrients. CONCLUSIONS: The QFFQ-method is suitable for use in a Norwegian nutritional surveillance system. SPONSORSHIP: National Nutrition Council, Ministry for Agriculture, Ministry for Health and Social Affairs and Norwegian Research Council.

The Norwegian diet during the last hundred years in relation to coronary heart disease.

OBJECTIVE: The influence of dietary changes on serum cholesterol and CHD during the last century in Norway has been evaluated. DESIGN: Data on food consumption are based on national food supply and household consumption surveys. To be able to calculate comparable series of the dietary content of energy, fat, saturated, monounsaturated and polyunsaturated fatty acids and dietary cholesterol, we compiled food composition data covering this century. The dietary effect on serum cholesterol was estimated by Keys equation. RESULTS: Changes in dietary lipids precede the increase and the decrease in mortality of CHD. The estimated serum cholesterol level in the population increased by approximately 1 mmol/l during 1900-1960, and decreased by approximately 0.6 mmol/l during 1960-1992. These changes correspond to a 60% increase and a 30% decrease in risk for CHD. However, the observed change in mortality of CHD was greater. During 1951-1955 and 1971-1975 it increased by 120% in men and 80% in women aged 50-59 years and during 1971-1975 and 1991-1993 it decreased by 43% and 29%, respectively. CONCLUSIONS: Change in dietary lipids have the potential to explain a great deal of the changes in mortality of CHD in Norway during this century. A reduced consumption of boiled coffee and an increase in the consumption of antioxidants may also have contributed to the reduced mortality of CHD the last 20 years.

Evaluation of a quantitative food frequency questionnaire used in a group of Norwegian adolescents.

OBJECTIVE: The study was conducted to assess the reproducibility and validity of a 190-item self-administered quantitative food frequency questionnaire, used in a nation-wide study of adolescents. DESIGN AND SUBJECTS: Reproducibility study; 103 11th grade students (18 years) completed the questionnaire twice, with a 6-week interval. Validation study; 49 11th grade students filled in the questionnaire and kept 7-day weighed food records. RESULTS: Spearman rank correlations between the nutrient intakes from the two questionnaires varied from 0.63 (sugar energy percentage) to 0.91 (alcohol). The median coefficient was 0.85. The first questionnaire produced generally higher nutrient intake estimates than the second. Correlations between nutrient intake values from the records and the questionnaire ranged from 0.14 (vitamin D, non-significant, cod liver oil not included) to 0.66 (monounsaturated fatty acids). The median coefficient was 0.52. Adjustment for energy intake did not materially affect the correlations. On average 41% of the subjects were classified in the same quartile in the questionnaire and the records, and 2% in the opposite quartiles. However, the percentage of subjects in the same/opposite quartiles for vitamin D and fibre were 33/12 and 22/6, respectively. CONCLUSIONS: It is concluded that the questionnaire is able to rank subjects according to the tested nutrients, except vitamin D and fibre.

Dietary intake among Norwegian adolescents.

OBJECTIVE: The aim of the nationwide study on dietary behaviour of adolescents was to describe and evaluate dietary habits, and relate that to other lifestyle factors. DESIGN AND SUBJECT: 1564 students in secondary schools completed a self-administered quantitative food frequency questionnaire in a school setting. RESULTS: The questionnaire showed an average energy intake of 15.8 and 9.9 MJ among boys and girls, respectively. Nearly 31% of the energy was supplied by fat and 11.4% by sugar. The average daily intake of micronutrients exceeded the Norwegian recommendations, except for vitamin D and iron in girls. 13.4% of the students had breakfast twice a week or less. These students had a higher percentage of energy from fat and sugar, and a lower intake of micronutrients, than students eating breakfast more often. Students who were daily smokers or fairly inactive had higher energy percentage from fat and sugar and lower intake of fibre, than non-smokers or physically active students. CONCLUSION: Half of the students consumed a diet with too much fat and two-thirds consumed too much sugar as compared to the recommendations. The girls had a diet with a higher nutrient density and a lower fat energy percentage than the boys. Finally, it seemed as if a healthy lifestyle was associated with a healthy diet.

[Recommendations of the Council for Nutrition on infant nutrition. Norwegian National Nutrition Council]. / Statens ernaeringsråds anbefalinger for spedbarnsernaering.

Because of the high frequency of nursing mothers there is concensus that, in general, the diet of Norwegian newborns is good for the first six months of life. However, several publications have questioned the recommendations concerning the babies' diet from the age of six to 12 months with respect to time of weaning and introduction of cow's milk, and intake of energy, fat-soluble vitamins, iron and essential fatty acids. The Norwegian National Nutrition Council has therefore evaluated the available data, and has adjusted some of the recommendations, including the recommendations for energy intake, energy percent from fat and essential polyunsaturated fatty acids.

Antioxidant status and alcohol-related diseases.

Chronic ethanol consumption is associated with increased incidence of a variety of illnesses, including cancer. Studies have shown that ethanol consumption may result in increased oxidative stress with formation of lipid peroxides and free radicals. The susceptibility of a given tissue to peroxidation is, however, a function of the overall balance between prooxidants and antioxidant defence systems. The latter involve both intracellular and extracellular protective factors were nutrients play an important role. Impaired nutritional status of different vitamins and trace elements have been reported in alcoholics. Reduced levels of vitamin E have been found in serum of alcoholics with and without liver disease and in liver biopsies from alcoholics with cirrhosis. These findings may be due to the increased oxidative stress as reported in experimental animals, and may be of importance since vitamin E is the major, if not the only, lipid-soluble free radical scavenger in some tissues. Reduced antioxidant capacity has been found in several tissues and may promote the generation of free radicals and lipid peroxides which may damage cells directly, induce inflammation and accelerate collagen synthesis. These events may progress to tissue damage and disease. The importance of radicals in cancer initiation and promotion is presently of great interest. The role of lipid peroxides and free radicals in alcohol-related disease and cancer remains unresolved. Further research is required to establish the role of these reactive species in the pathogenesis of alcohol-related disease, and to evaluate the role of nutrition in favour of the antioxidant defence mechanisms.

[The Norwegian diet is steadily improving]. / Norsk kosthold blir stadig bedre.

The main goal of the Norwegian food and nutrition policy for the period 1975-1990 was to reduce the fat content in the diet to 35% of the energy supply. Our latest data on food supply and consumption show that this target has been reached, and that dietary fat now contributes to 34% of the energy. The dietary changes have probably contributed to the decrease in cardiovascular disease that has taken place since the early 1970s. It is most likely that public health continue to improve through further changes in diet, and the National Nutrition Council has prepared a strategy aimed at achieving a Norwegian diet with a fat content providing only 30% of the energy supply.

Effect of dietary deficiency and supplementation with all-rac-alpha-tocopherol on hepatic content in rats.

We studied the effect of dietary deficiency and supplementation with vitamin E in the form of all-rac-alpha-tocopherol in relation to the content of alpha-tocopherol in parenchymal and nonparenchymal liver cells. The cells were isolated by centrifugal elutriation from rats fed diets containing normal, low or high amounts of vitamin E. The parenchymal cells contained about 90% of total hepatic alpha-tocopherol content in rats fed a nonpurified diet (reference group). However, the Kupffer and the endothelial/stellate cells contained four and two times more alpha-tocopherol, respectively, than the parenchymal cells per milligram of cell protein. When the rats were deprived of vitamin E for 8 wk, the content of alpha-tocopherol in parenchymal cells was reduced to 30% of values obtained from rats fed the nonpurified diet, and nonparenchymal cells contained very low levels of alpha-tocopherol (less than 5% of reference values). A diet enriched in vitamin E resulted in a sixfold increase in the content of alpha-tocopherol in parenchymal cells but in small changes in nonparenchymal cells compared to the reference diet. Accordingly, the parenchymal cells may have storage capacity for alpha-tocopherol. The light mitochondrial and microsomal fractions contained high amounts of alpha-tocopherol. These fractions were subdivided by density gradient centrifugation to examine the alpha-tocopherol content in different cell organelles. The lysosomes and the Golgi apparatus were found to contain high levels of alpha-tocopherol, whereas peroxisomes contained small amounts.

[New aspects of the treatment of psoriasis]. / Nye aspekter ved behandling av psoriasis.

Psoriasis is an inflammatory condition of the skin which affects about 2% of the population. Several new treatment modalities have been introduced in recent years. This review considers the mode of action of various forms of treatment, side effects and therapeutic results that have been observed. Etretinate is a synthetic vitamin A analogue. It works alone, or even better in combination with psoralen plus ultraviolet light A (PUVA) or ultraviolet light B (UVB). Cyclosporin is still on trial, but seems to be effective in small doses and can be considered as an alternative in cases of psoriasis that are resistant to other therapies. The interest in dietary measures for psoriasis has been revived after some studies have suggested that dietary supplements of fish oil, a low-fat diet, can improve the condition. Now that n-3-fatty acids are available in capsule form it should be possible to prescribe a diet that is rich enough in fish oils.

Axial and appendicular bone mineral content determined by computed tomography. Relationship to age and body size in males.

Bone density and mass related values were determined in femoral condyles and in the second lumbar vertebra in males of middle age. A poor agreement was found between measurements in the two locations. The measurements were compared with age and body size by means of correlation analysis and multiple regression analysis. There was a significant linear relationship between lumbar measures and age (beta coefficient -0.61 and -0.75) while the relationship with age for the femoral measures was less (beta -0.36 and -0.45). For all measurements there was a poor correlation with body size (weight, length and surface area). Bone mineral content measurements in the lumbar and appendicular skeleton have different clinical implications. When selecting a method for estimating the bone mineral content careful attention must be paid to what type of information is wanted and whether the method is adequate for that particular purpose.

Absorption, transport and distribution of vitamin E.

Vitamin E is the term used for eight naturally occurring fat-soluble nutrients called tocopherols. alpha-Tocopherol is essential, has the highest biological activity and predominates in many species. In humans vitamin E is the most important lipid soluble antioxidant and deficiency may cause neurological dysfunction, myopathies and diminished erythrocyte life span. alpha-Tocopherol is absorbed via the lymphatic pathway and transported in association with chylomicrons. In plasma, alpha-tocopherol is found in all lipoprotein fractions but mostly is associated with apo B-containing lipoproteins. alpha-Tocopherol is associated with very-low-density lipoprotein when it is secreted from the liver. In the rat, about 90% of total body mass of alpha-tocopherol is recovered in the liver, skeletal muscle and adipose tissue. Most alpha-tocopherol is located in the mitochondrial fractions and in the endoplasmic reticulum, whereas little is found in cytosol and peroxisomes. New clinical evidence from heavy drinkers and from experimental work in rats suggests that alcohol may increase oxidation of alpha-tocopherol. Increased demand for vitamin E has also been observed in premature infants and patients with malabsorption, but there is little evidence that the healthy population requires supplementation of vitamin E to a well-balanced diet.

Effect of chronic ethanol consumption on the content of alpha-tocopherol in subcellular fractions of rat liver.

The effects of long-term administration of ethanol (35% of total energy for 6-8 weeks) on the distribution and concentration of alpha-tocopherol in subcellular fractions of rat liver have been studied. Marker enzymes were measured in all fractions. The highest concentration of alpha-tocopherol was found in the light mitochondrial fraction both in ethanol-fed and control rats, 754 +/- 104 and 1127 +/- 126 pmol/mg protein, respectively. The microsomal, heavy mitochondrial, and nuclear fractions also had high concentrations of alpha-tocopherol, whereas the cytosolic fraction contained minor amounts. In the light mitochondrial fraction we found the highest concentration of alpha-tocopherol in lysosomes, whereas small amounts were detected in peroxisomes. In the microsomal fraction the highest concentration was found in the Golgi apparatus. The content of alpha-tocopherol in the light mitochondrial fraction was reduced by 33% (p less than 0.02) in the ethanol-fed group as compared to the controls. In the other fractions no significant differences between the two groups were observed. Long term administration of ethanol promoted, however, a further enrichment of alpha-tocopherol (178% higher than controls) in the Golgi apparatus, possibly due to reduced secretion of very low density lipoprotein-associated alpha-tocopherol.