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L B Rasmussen

Publications and source records attributed to L B Rasmussen.

At least 19 recordsLinked to original sources
PubMed2001

Evaluation of a semi-quantitative food frequency questionnaire to estimate iodine intake.

OBJECTIVE: To evaluate a food frequency questionnaire (FFQ) used to assess the dietary intake of iodine. DESIGN: The iodine intake determined by the FFQ was compared with 4-day dietary records and with iodine excretion in 24 h urine samples in a subgroup of participants in a cross-sectional study of iodine intake and thyroid diseases in Denmark. Furthermore, the intake of fish determined from the FFQ was compared with the intake of fish from a simple record kept for 3 months. SUBJECTS: Women aged 25-30 y and 60-65 y. RESULTS: Median iodine intake was similar when determined from the FFQ and from dietary records and the correlation between these measures was 0.52 (P < 0.001). Iodine intake was higher than iodine excretion (P < 0.001). The cross-check questions in the FFQ (for example the question 'How often did you get any kind of fish?') underestimated the intake. In contrast, the intake of a specific fish tended to be overestimated by the FFQ when compared with the 3 month record of fish intake. CONCLUSION: The FFQ can be used to classify subjects into low and high iodine intake groups, but the level of iodine tends to be overestimated.

Adult↗
PubMed2000

Iodine content in drinking water and other beverages in Denmark.

OBJECTIVE: To investigate the variation in iodine content in drinking water in Denmark and to determine the difference in iodine content between organic and non-organic milk. Further, to analyse the iodine content in other beverages. DESIGN AND SETTING: Tap water samples were collected from 41 evenly distributed localities in Denmark. Organic and non-organic milk was collected at the same time (twice summer and twice winter). Soft drinks, beers and juice were collected from different Danish producers and wine from different countries. All samples were analysed for iodine using inductively coupled mass spectrometry. RESULTS: Iodine in tap water varied from 2.1 to 30.2 microg/l; the iodine content was in general highest in the eastern part of Denmark and lowest in the western part of Denmark. Organic milk was found to have a lower iodine content than non-organic milk. CONCLUSIONS: Large geographical (and seasonal) variations in iodine concentrations were found in different beverages supplying an appreciable part of the iodine in the Danish diet. This knowledge is important when calculating the iodine intake from dietary intake studies. SPONSORSHIP: The 1991 Farmacy Foundation and Danish Veterinary and Food Administration. European Journal of Clinical Nutrition (2000) 54, 57-60

Animals↗
PubMed2000

Vitamin D: should the supply in the Danish population be increased?

A working group was established to evaluate the need for an increased vitamin D intake in the Danish population. Vitamin D is primarily important for calcium homeostasis, calcium absorption in the intestine and calcium content in bones, and thereby for the strength of the bones. Only a few foods provide vitamin D and the intake in the Danish population is low compared to the recommendation. However, vitamin D is also produced by the skin from solar exposure. How much vitamin D is provided this way is not known but it is said to be the most important source. Measures of vitamin D status and clinical signs of vitamin D status are therefore important when assessing the possible need for increased vitamin D intake. Measures of vitamin D status have shown a low status in the elderly but not in the young. More than 50% of nursing-home residents have low blood vitamin D levels and many have biochemical signs of osteomalacia. Vitamin D deficiency increases the risk of osteoporosis. In Denmark, for instance, 13,000 admissions each year are caused by hip fractures alone, almost all among elderly people. Dark-skinned women often constitute a problem with respect to vitamin D sufficiency because of reduced production from the skin secondary to extensive covering, skin pigmentation and many hours spent indoors. It is concluded that the elderly and dark-skinned (veiled) women will benefit from an increased vitamin D supply. Four strategies to increase vitamin D supply were considered: dietary changes, increased solar exposure, dietary supplements with vitamin D and food fortification with vitamin D. It is concluded that the best solution is to recommend dietary supplements with vitamin D to elderly over 65 years, dark-skinned and veiled women and people who, because of disease, are unable to spend time outdoors.

Age Factors↗
PubMed2000

Folate intake, lifestyle factors, and homocysteine concentrations in younger and older women.

BACKGROUND: An elevated total homocysteine (tHcy) concentration is considered to be an independent risk factor for cardiovascular diseases and has also been associated with an increased risk of neural tube defects. OBJECTIVE: The objective of this study was to investigate folate intake, folate status, and the association between folate intake, other dietary and lifestyle factors, and tHcy concentrations in young and older women. DESIGN: tHcy concentrations were measured in 290 young women aged 25-30 y and in 288 older women aged 60-65 y. All participants completed questionnaires about factors including lifestyle, health, and use of vitamin supplements. Red blood cell folate was measured in 204 of the participants. A subgroup of 258 participants completed dietary records. RESULTS: Median tHcy was 7.6 micromol/L (range: 6.5-8.9) in the younger women and 9.4 micromol/L (7.7-11.1) in the older women. Folate intake from diet was 283 (224-348) and 268 (210-326) microg/d, respectively, in the 2 age groups. Folic acid intake from supplements (P: < 0.001 for the younger women and P: = 0.026 for the older women) and total folate intake (P: = 0.024 and P: = 0.079) were inversely associated with log tHcy in multiple linear regression analyses. Smoking status, coffee consumption, systolic blood pressure, and body mass index were positively associated and estrogen replacement therapy and tea consumption were inversely associated with log tHcy in some of the models. CONCLUSIONS: According to the criteria used, between 1% and 36% of the women had suboptimal folate intake. Folic acid is a strong predictor of tHcy concentration; however, several dietary and other lifestyle factors seem to be important as well.

Adult↗
PubMed1999

Day-to-day and within-day variation in urinary iodine excretion.

OBJECTIVE: To examine the day-to-day and within-day variation in urinary iodine excretion and the day-to-day variation in iodine intake. DESIGN: Collection of consecutive 24-h urine samples and casual urine samples over 24h. SETTING: The study population consisted of highly motivated subjects from our Institute. SUBJECTS: Study 1: Ten healthy subjects (seven females and three males) aged 30-46 y. Study 2: Twenty-two healthy subjects (9 males and 13 females) aged 30-55 y. METHODS: Study 1: 24-h urine samples were collected for four consecutive days. Study 2: Each urine voided over 24 h was collected into separate containers. In both studies dietary records were kept. MAIN OUTCOME MEASURES: Twenty-four-hour urinary iodine excretion, 24-h urinary iodine excretion estimated as I/Cr*24 h Cr and as a concentration in casual urine samples. RESULTS: Study 1: Both iodine excreted in 24-h urine and iodine intake varied from day-to-day. Iodine excretion correlated with iodine intake (=-0.46, P=0.01). Iodine intake (mean 89 +/- 6.5 microg/d) was not significantly different from iodine excretion (mean 95 +/- 5.3 microg/d). Study 2: Twenty-four hour iodine excretion estimated as I/Cr*24 h Cr from the morning urine sample was significantly lower than actual 24-h iodine excretion, whereas 24-h iodine excretion estimated as I/Cr*24 h Cr from the first sample after the morning sample and the last sample before the subjects went to bed was not significantly different from actual 24-h iodine excretion. Twenty-four-hour urine excretion estimated as a concentration was lower than actual 24-h iodine excretion in casual urine taken at any time of the day. CONCLUSIONS: For determination of iodine status in an individual, more than one 24-h urine sample must be used. The use of the I/Cr ratio in casual urine samples is a usable measure of iodine status if corrected for the age- and sex-adjusted 24-h creatinine excretion. Further, the study suggests that fasting morning urine samples would underestimate iodine status in this population.

Adult↗
PubMed1998

Folate and neural tube defects. Recommendations from a Danish working group.

A working group was established to evaluate the need for an increased folate intake in Danish women to decrease the risk of neural tube defects (NTDs). NTD are birth defects which include anencephaly, encephalocele and spina bifida. In Denmark the incidence is about 1.4 per 1,000 pregnancies. Folate is a B-vitamin found in most food groups. In case-control studies and randomised studies, a protective effect of folic acid supplements on NTDs has been found. The studies show that a periconceptional folic acid supplement of 360 micrograms to 4 mg daily decreases the recurrence rate of NTDs. Likewise, in the few studies which calculate folate intake from the diet, a lower risk of NTD with higher intake of folate from the diet has been found. The folate intake can be increased by the diet, by folic acid supplements or by fortification of food with folic acid. It is concluded that the incidence of NTDs in Denmark will decrease if the folate intake in fertile women increases. All women planning pregnancy should receive dietary counselling. Women who do not eat according to the Nordic Nutrition Recommendations, and women with an increased risk due to diseases are recommended a supplement of 400 micrograms folic acid daily from a multivitamin/folic acid tablet. Women who have had a child with NTD and women who themselves have NTDs are recommended a supplement of 5 mg folic acid daily. Dietary changes and supplements should be initiated when pregnancy is planned.

Adolescent↗
PubMed1996

Iodine. Do we need an enrichment program in Denmark?

A working group was established to evaluate the need for iodine enrichment in Denmark. Judged from studies of urinary iodine excretion and one dietary survey the intake of iodine in Denmark is low compared with recommended intakes. The occurrence of non-toxic goitre is relatively high; between 9 and 13% in elderly women. Furthermore, a high occurrence of toxic goitre has been seen in the western part of Denmark. On the other hand, an increased or a high intake of iodine may lead to hyperthyroidism and thyroiditis. The working group concluded that an increase in iodine intake in the Danish population is needed and the best way to achieve this is to iodize all salt. To avoid side effects of a sudden large increase in iodine intake the initial amount of iodine in salt will only be 2 ppm.

Animals↗
PubMed1994

[Significance of fatty acid composition in plasma and in food for cellular immune function in elderly men].

The relation between fatty acid composition in plasma and natural killer (NK) cell activity and the relation between fatty acid composition of diet and NK cell activity was evaluated in healthy elderly men. The correlations between basal NK activity and the fraction of plasma fatty acids consisting of total polyunsaturated fatty acids (PUFA), total n-6 fatty acids and linoleic acid were r = -0.68, p = 0.006, r = 0.62, p = 0.014 and r = 0.52, p = 0.048, respectively. Significant negative correlations were also found between alpha-interferon stimulated NK cell activity and the three groups of fatty acids and between interleukin-2 stimulated NK cell activity and PUFA. Likewise, negative correlations between grammes of PUFA in diet, determined from two four-day registration-periods, and basal NK and alpha-interferon stimulated NK cell activity were found. No significant negative correlation between percentage intake of n-3 fatty acids and NK cell activity was found. It is concluded that the type of dietary fatty acids influence NK cell activity in elderly men. A high intake of n-6 polyunsaturated fatty acids may be detrimental to cellular immune defence mechanisms in the elderly.

Aged↗
PubMed1994

Effect of diet and plasma fatty acid composition on immune status in elderly men.

The relationship between fatty acids in plasma and basal (B), interleukin-2-(IL-2), and interferon-alpha (IFN-alpha)-stimulated natural killer (NK) cell activity was studied in healthy elderly men aged on average 70.5 y (65-81 y). B-NK correlated significantly with the fraction of plasma fatty acids consisting of total polyunsaturated fatty acids (PUFAs), total n-6 fatty acids, and linoleic acid (r = -0.68, r = -0.62, and r = -0.52, respectively). Significant negative correlations were also found between IFN-alpha stimulated NK cells and the three groups of fatty acids and between IL-2-stimulated NK cells and PUFAs. Likewise, negative correlations between PUFAs in the diet and B-NK, IL-2 and IFN-alpha stimulated NK cell activity were found. The number of NK cells increased significantly but NK cell activity did not change after 5 wk on a diet lower in fat but higher in PUFAs than the subjects' habitual diet. It is concluded that the amount and type of dietary fatty acids influence in vitro measures of immune function in elderly men. From an immunological point of view, a high intake of n-6 PUFAs may be inadvisable.

Aged↗