INTRODUCTION: The aim of the present study was to quantify the impact of different dietary factors on the mortality from ischaemic heart disease in Denmark. METHODS: Relative risks and knowledge on the distribution of different dietary factors were used to estimate etiological fractions. RESULTS: It is estimated that an intake of fruit and vegetables and saturated fat as recommended would prevent 12 and 22%, respectively, of deaths from ischaemic heart disease in Denmark. An intake of fish among those at high risk for ischaemic heart disease, would lead to a 26% lower mortality, while alcohol intake among abstainers would have no significant quantitative effect. DISCUSSION: These results suggest that changes in dietary habits according to current recommendations would have an impact on public health in Denmark.
In the early 1980s, Doll and Peto estimated that about 35% of all deaths from cancer in the United States were attributable to dietary factors, with a margin of uncertainty ranging from 10 to 70%. Since then, several dietary factors, e.g. fat and meat, have been suggested to increase the risk for cancer, while other factors, e.g. fibre, fruit and vegetables, have been suggested to decrease the risk. The case-control and cohort studies have, however, given ambiguous results, and the overall evidence is far from conclusive. The major findings on dietary factors that increase risk have been reported from case-control studies, but have not been confirmed in large population-based cohort studies. Although the research in this area indicates that diet is important in cancer prevention, current knowledge does not allow reliable estimates of the numbers and proportions of cancers that could be avoided through well-described modifications of dietary habits. During the last 10 years, low physical activity has been pinpointed as a risk factor for cancers at various sites, especially the colon; however, the causal mechanism is still unknown. Obesity, defined as a body mass index of 30 or more, is consistently associated with endometrial and gall-bladder cancers in women and renal-cell cancer in both men and women. As the prevalence of obesity was between 5 and almost 20% in the Nordic populations in 1995, 625 cancer cases (310 endometrial cancers, 270 renal-cell cancers in men and women and 45 gall-bladder and bile-duct cancers among women) can be predicted in the Nordic countries around the year 2000 to be caused by obesity. This implies that about 1% of all cancers in Nordic women and less than 1% of those in Nordic men could be avoided around the year 2000 if a healthy body weight could be maintained by all inhabitants.
The evidence regarding fatty acids and breast cancer risk is inconclusive. Adipose tissue fatty acids can be used as biomarkers of fatty acid intake and of endogenous fatty acid exposure. Fatty acids in adipose tissue are correlated owing to common dietary sources and shared metabolic pathways, which group fatty acids into naturally occurring patterns. We aimed to prospectively investigate associations between adipose tissue fatty acid patterns and long-term risk of total breast cancer and breast cancer subtypes characterised by oestrogen and progesterone receptor status (ER and PR).
This case-cohort study was based on data from the Danish cohort Diet, Cancer and Health. At baseline, a fat biopsy and information on lifestyle and reproductive factors were collected. From the 31 original fatty acids measured, patterns of fatty acids were identified using the treelet transform. During a median follow-up of 5.3 years, 474 breast cancer cases were identified. Hazard ratios and 95% confidence intervals of risk of total breast cancer and of subtypes according to quintiles of factor score were determined by weighted Cox proportional hazards regression.
After adjustment for potential confounders, factor scores for the seven patterns identified by the treelet transform were not associated with risk of total breast cancer, nor with risk of ER+, ER-, PR+ or PR- tumours.
No clear associations between the patterns of fatty acids at baseline and long-term risk of total breast cancer or ER+, ER-, PR+ or PR- tumours were observed.
Obesity is a modifiable risk factor for acute myocardial infarction (MI), but lean body mass (LBM) may also be an important factor. Low LBM may increase the risk of MI and LBM may modify the effect of obesity on MI. Thus, the inability of the classical anthropometric measures to evaluate LBM may lead to misclassification of MI risk in both lean and obese persons. We investigated the associations between incident MI and bioelectrical impedance analyses (BIA) derived measures of body composition in combination with body mass index (BMI) and anthropometric measures of body fat distribution.
From 1993 to 1997, 27?148 men and 29?863 women, aged 50 to 64 year, were recruited into the Danish prospective study Diet, Cancer and Health. During 11.9 years of follow-up we identified 2028 cases of incident MI (1487 men and 541 women). BMI, waist circumference (WC), hip circumference and BIA of body composition including body fat mass (BFM), body fat percentage and LBM were measured at baseline. We used Cox proportional hazard models with age as time axis and performed extensive control for confounding. Weight, BMI, classical estimates of abdominal obesity and BIA estimates of obesity showed significant positive associations with incident MI. However, BFM adjusted for WC showed no association. Low LBM was associated with a higher risk of incident MI in both genders, and high LBM was associated with a higher risk in men.
Obesity was positively associated with MI. Estimates of obesity achieved by BIA seemed not to add additional information to classical anthropometric measures regarding MI risk. Both high and low LBM may be positively associated with MI.
In order to test hypotheses on diet and the risk of cancer, a prospective cohort study was established. A total of 57,055 persons living in Copenhagen and Aarhus, between 50 and 65 years of age, visited a study clinic between December 1993 and May 1997. The participants provided questionnaire data on diet and lifestyle. Furthermore, anthropometric measurements, blood pressure and biological material were collected. All participants will be followed by linkage to health registries including the Cancer Registry and by self-administered follow-up questionnaires. The purpose of this publication is to describe the data-base, which will be available for research in the years to come including the results of the first two years of follow-up.
General practitioners (GPs) in Denmark (n = 374) answered a questionnaire on attitudes toward including information on diet and sex in the prevention of coronary artery disease, cancers, osteoporosis, and weight problems. Risk factors for disease were ranked as follows: smoking, alcohol, stress, diet, physical exercise, heredity, and hygiene. Patients' lack of motivation, insufficient time for each patient, and inadequate knowledge about nutrition were listed by GPs as barriers to dietary counseling. GPs stated that the sex of the patient was important only for counseling on osteoporosis. Lack of time and insufficient knowledge were perceived as barriers to including sex-specific issues in prevention. One-half of the GPs were questioned about the issue of prevention on the basis of female case stories and the other half on the basis of male case stories with identical wording. Responses to the case stories indicated that GPs would give dietary guidance and recommend loss of weight to slightly overweight male patients to a much greater degree than to overweight female patients for prevention of coronary artery disease, give dietary counseling and recommend loss of weight and exercise to female patients more than to male patients for prevention of cancers, recommend a supplement of calcium and vitamin D for prevention of osteoporosis to female patients, and recommend weight gain and discuss psychosocial issues more with underweight female patients than with underweight male patients. Female GPs included measures of prevention such as dietary counseling, exercise prescription, dietary supplement prescription, and discussion of psychosocial issues to a greater extent than did male GPs.
BACKGROUND: Psychological stress and alcohol are both suggested as risk factors for stroke. Further, there appears to be a close relation between stress and alcohol consumption. Several experimental studies have found alcohol consumption to reduce the immediate effects of stress in a laboratory setting. We aimed to examine whether the association between alcohol and stroke depends on level of self-reported stress in a large prospective cohort. METHODS: The 5,373 men and 6,723 women participating in the second examination of the Copenhagen City Heart Study in 1981-1983 were asked at baseline about their self-reported level of stress and their weekly alcohol consumption. The participants were followed-up until 31st of December 1997 during which 880 first ever stroke events occurred. Data were analysed by means of Cox regression modelling. RESULTS: At a high stress level, weekly total consumption of 1-14 units of alcohol compared with no consumption seemed associated with a lower risk of stroke (adjusted RR: 0.57, 95% CI: 0.31-1.07). At lower stress levels, no clear associations were observed. Regarding subtypes, self-reported stress appeared only to modify the association between alcohol intake and ischaemic stroke events. Regarding specific types of alcoholic beverages, self-reported stress only modified the associations for intake of beer and wine. CONCLUSIONS: This study indicates that the apparent lower risk of stroke associated with moderate alcohol consumption is confined to a group of highly stressed persons. It is suggested that alcohol consumption may play a role in reducing the risk of stroke by modifying the physiological or psychological stress response.
Obesity may be associated with increased risk of pneumonia, but available data on this relationship are sparse and inconsistent. We followed a prospective cohort of 22,578 males and 25,973 females from the Danish Diet, Cancer and Health Study, aged 50-64 yrs and free from major chronic diseases at baseline (1993-1997), for first-time hospitalisation with pneumonia (median follow-up 12 yrs). Compared with males of normal weight, adjusted hazard ratios (HRs) for pneumonia were 1.4 (95% CI 1.2-1.7) for males with moderate obesity (body mass index (BMI) 30.0-34.9 kg·m?²), and 2.0 (95% CI 1.4-2.8) for males with severe obesity (BMI = 35.0 kg·m?²), controlling for lifestyle and educational variables. Among females the associations were weaker, with adjusted HRs of 0.8 (95% CI 0.6-1.0) for moderate obesity, and 1.2 (95% CI 0.8-1.6) for severe obesity. Adjustment for major chronic diseases diagnosed during follow-up eliminated the associations between obesity and pneumonia risk. Obesity is associated with higher risk of hospitalisation with pneumonia among males but not among females, which is apparently explained by occurrence of other chronic diseases.
Comment In: Eur Respir J. 2011 May;37(5):1298; author reply 1299-130021532024
Comment In: Eur Respir J. 2011 May;37(5):1299; author reply 1299-130021532025