Breast cancer may be related to oxidative stress. Breast cancer patients have been reported to have lower antioxidant enzyme activity than healthy controls and the polymorphism GPX1 Pro198Leu has been associated with risk of lung and breast cancer. The purpose of the present nested case-control study was to determine whether GPX1 Pro198Leu and glutathione peroxidase (GPX) activity in prospectively collected blood samples are associated with breast cancer risk among postmenopausal women and whether GPX activity levels are associated with other known breast cancer risk factors. We matched 377 female breast cancer cases with 377 controls all nested within the prospective 'Diet, Cancer and Health' study of 57 000 Danes. Carriers of the variant T-allele of GPX1 Pro198Leu were at 1.43-fold higher risk of breast cancer compared with non-carriers (95% CI=1.07-1.92). Pre-diagnostic GPX activity tended to be lower in cases compared with controls. GPX activity was positively correlated with intake of alcohol (P
Self-reported dietary intake does not represent an objective unbiased assessment. The effect of the new Nordic diet (NND) versus average Danish diet (ADD) on plasma metabolic profiles is investigated to identify biomarkers of compliance and metabolic effects.
In a 26-week controlled dietary intervention study, 146 subjects followed either NND, a predominantly organic diet high in fruit, vegetables, whole grains, and fish, or ADD, a diet higher in imported and processed foods. Fasting plasma samples are analyzed with untargeted ultra-performance liquid chromatography-quadruple time-of-flight. It is demonstrated that supervised machine learning with feature selection can separate NND and ADD samples with an average test set performance of up to 0.88 area under the curve. The NND plasma metabolome is characterized by diet-related metabolites, such as pipecolic acid betaine (whole grain), trimethylamine oxide, and prolyl hydroxyproline (both fish intake), while theobromine (chocolate) and proline betaine (citrus) were associated with ADD. Amino acid (i.e., indolelactic acid and hydroxy-3-methylbutyrate) and fat metabolism (butyryl carnitine) characterize ADD whereas NND is associated with higher concentrations of polyunsaturated phosphatidylcholines.
The plasma metabolite profiles are predictive of dietary patterns and reflected good compliance while indicating effects of potential health benefit, including changes in fat metabolism and glucose utilization.
Individual lifestyle factors have been associated with lifestyle diseases and premature mortality by an accumulating body of evidence. The impact of a combination of lifestyle factors on mortality has been investigated in several studies, but few have applied a simple index taking national guidelines into account. The objective of the present prospective cohort study was to investigate the combined impact of adherence to five lifestyle factors (smoking, alcohol intake, physical activity, waist circumference and diet) on all-cause, cancer and cardiovascular mortality based on international and national health recommendations. A Cox proportional hazards model was used to estimate hazard ratios (HR) with 95 % CI. During a median follow-up of 14 years, 3941 men and 2827 women died. Among men, adherence to one additional health recommendation was associated with an adjusted HR of 0·73 (95 % CI 0·71, 0·75) for all-cause mortality, 0·74 (95 % CI 0·71, 0·78) for cancer mortality and 0·70 (95 % CI 0·65, 0·75) for cardiovascular mortality. Among women, the corresponding HR was 0·72 (95 % CI 0·70, 0·75) for all-cause mortality, 0·76 (95 % CI 0·73, 0·80) for cancer mortality and 0·63 (95 % CI 0·57, 0·70) for cardiovascular mortality. In the present study, adherence to merely one additional health recommendation had a protective effect on mortality risk, indicating a huge potential in enhancing healthy lifestyle behaviours of the population.
It has been suggested that antioxidants attenuate oxidative stress and prevent oxidative stress-related diseases. Paradoxically, randomised controlled trials (RCT) using pharmacological doses of antioxidant supplements have demonstrated harmful effects in smokers. The aim of the present study was to test the compliance, tolerability and safety of two food-based antioxidant-rich diets in smokers. One of the diets provided antioxidants at levels similar to that used in RCT using supplements which previously have generated harmful effects. The present study followed a randomised, parallel-arm dietary intervention for 8 weeks (n 102) in male smokers (age = 45 years). Participants were randomised to either antioxidant-rich diet, kiwi fruit or control groups. The antioxidant-rich foods provided about 300 mmol antioxidants/week from a wide range of plant-based food items. The kiwi fruit group consumed three kiwi fruits/d. Compliance to both diets was good. Only mild, undesirable events were reported by a minority of the participants. The safety of both diets was demonstrated as no potentially harmful or pro-oxidative effects were observed. In the antioxidant-rich diet group, the mean intake of antioxidants increased from 30 mmol/d at baseline to 62 mmol/d during the intervention. In conclusion, we have demonstrated that male smokers can comply with two food-based antioxidant-rich diets. Furthermore, the present study is the first to demonstrate the tolerability and safety of dietary antioxidants at levels similar to dosages provided in RCT using supplements. Such diets may be useful in future studies investigating whether dietary antioxidants may reduce oxidative stress and related diseases.
The prevalence of dietary supplement use varies largely among populations, and previous studies have indicated that it is high in the Danish population compared with other European countries. The diversity in supplement use across countries indicates that cultural and environmental factors could influence the use of dietary supplements. Only few studies investigating the use of dietary supplements have been conducted in the Danish population. The present cross-sectional study is based on 54,948 Danes, aged 50-64 years, who completed self-administrated questionnaires on diet, dietary supplements and lifestyle between 1993 and 1997. A health index including smoking, physical activity, alcohol and diet, and a metabolic risk index including waist circumference, urinary glucose and measured hypertension were constructed. Logistic regression was used to investigate these determinants in relation to the intake of dietary supplements. We found that 71 % of the participants were dietary supplement users; female sex, older age groups and higher educated participants were more likely to be users of any dietary supplements. One additional point in the health index was associated with 19, 16 and 9 % higher likelihood of being user of any, more common and less common supplements, respectively. In the metabolic risk index, one additional point was associated with 17 and 16 % lower likelihood of being user of any supplement and more common supplements, respectively. No significant association was found for less common supplement use. In conclusion, those with the healthiest lifestyle were more likely to use dietary supplements. Thus, lifestyle and dietary composition should be considered as confounders on supplement use and health outcomes.
Effects of a healthy Nordic diet on gene expression changes in peripheral blood mononuclear cells in response to an oral glucose tolerance test in subjects with metabolic syndrome: a SYSDIET sub-study.
Diet has a great impact on the risk of developing features of metabolic syndrome (MetS), type 2 diabetes mellitus (T2DM), and cardiovascular diseases (CVD). We evaluated whether a long-term healthy Nordic diet (ND) can modify the expression of inflammation and lipid metabolism-related genes in peripheral blood mononuclear cells (PBMCs) during a 2-h oral glucose tolerance test (OGTT) in individuals with MetS.
A Nordic multicenter randomized dietary study included subjects (n?=?213) with MetS, randomized to a ND group or a control diet (CD) group applying an isocaloric study protocol. In this sub-study, we included subjects (n?=?89) from three Nordic centers: Kuopio (n?=?26), Lund (n?=?30), and Oulu (n?=?33) with a maximum weight change of ±4 kg, high-sensitivity C-reactive protein concentration =10 mg L(-1), and baseline body mass index
Prospective epidemiological studies have reported that a higher fruit and vegetable intake is associated with a lower risk of CHD. The aim of the present study was to examine associations between fruit and vegetable consumption, in particular the subgroupings citrus fruits, apples and cruciferous vegetables, and the risk of acute coronary syndrome (ACS). During a median follow-up of 7.7 years, 1075 incident ACS cases were identified among 53 383 men and women, aged 50-64 years at recruitment into the Diet, Cancer and Health cohort study in 1993-7. Fruit and vegetable intake was estimated from a validated FFQ, and ACS incidence rate ratios (IRR) were estimated using Cox proportional hazards models. Overall, a tendency towards a lower risk of ACS was observed for both men and women with higher fruit and vegetable consumption. For men, we found an inverse association for apple intake (IRR per 25 g/d: 0.97; 95 % CI 0.94, 0.99). This association was also seen among women, albeit borderline significant. However, a higher risk was seen among women with higher fruit juice intake (IRR per 25 g/d: 1.04; 95 % CI 1.00, 1.08). The present results provide some support for previously observed inverse associations between fresh fruit intake, particularly apples, and ACS risk.
Previously, a healthy Nordic diet (ND) has been shown to have beneficial health effects close to those of Mediterranean diets.
The objective was to explore whether the ND has an impact on gene expression in abdominal subcutaneous adipose tissue (SAT) and whether changes in gene expression are associated with clinical and biochemical effects.
Obese adults with features of the metabolic syndrome underwent an 18- to 24-wk randomized intervention study comparing the ND with the control diet (CD) (the SYSDIET study, carried out within Nordic Centre of Excellence of the Systems Biology in Controlled Dietary Interventions and Cohort Studies). The present study included participants from 3 Nordic SYSDIET centers [Kuopio (n = 20), Lund (n = 18), and Oulu (n = 18)] with a maximum weight change of ?4 kg, highly sensitive C-reactive protein concentration
The role of dietary fiber on the risk of colon and rectal cancer has been investigated in numerous studies, but findings have been inconsistent. The purpose of this study was to examine associations between intake of dietary fiber and risk of incident colon (including distal and proximal colon) and rectal cancer in the prospective Scandinavian HELGA cohort and to determine if fiber source (vegetables, fruits, potatoes, cereals) impacted the association. We included 1,168 incident cases (691 colon, 477 rectal cancer), diagnosed during a median of 11.3 years, among 108,081 cohort members. Sex-specific incidence rate ratios (IRRs) of colon and rectal cancer were related to intake of total or specific fiber source using Cox proportional hazards models. For men, an inverse association was observed between intake of total fiber and the risk of colon cancer per an incremental increase of 10 g day(-1) , IRR (95% CI): 0.74 (0.64-0.86). Intake of cereal fiber per 2 g day(-1) was associated with an IRR of 0.94 (0.91-0.98), which was also seen for intake of cereal fiber from foods with high fiber content (= 5 g per 100 g product), where the IRR per 2 g day(-1) was 0.94 (0.90-0.98). In women, intake of cereal fiber per 2 g day(-1) was also associated with lower risk of colon cancer, 0.97 (0.93-1.00). No clear associations were seen for rectal cancer. Our data indicate a protective role of total and cereal fiber intake, particularly from cereal foods with high fiber content, in the prevention of colon cancer.
OBJECTIVE: The influence of the vitamins A, C, and E on breast cancer development has not been clarified. An effect of a vitamin per se implicates similar patterns for the effects of the vitamin from dietary and supplemental sources. We examined how the breast cancer incidence rate among postmenopausal women was related to intake of vitamins A, C, and E from diet and supplements. METHODS: Data was sampled as case-control nested within the Danish 'Diet, Cancer and Health' cohort. Data on vitamin intakes were collected at entry into the cohort by means of self-administered questionnaires. Women eligible for the nested case-control study were postmenopausal at entry into the cohort. The analyses were based on 418 cases of incident breast cancer and 394 controls (including two cases). RESULTS: Breast cancer was not significantly related to the intakes of vitamin A or E, whereas a monotonic dose-response relation was seen for the intake of vitamin C. The estimated rate ratio per 100 mg vitamin C was: 2.06 (95% CI: 1.45-2.91) for dietary intake and 1.06 (95% CI: 1.01-1.13) for supplemental intake. CONCLUSIONS: We found no evidence of an association between breast cancer and intake of vitamin A or E for postmenopausal women. For vitamin C we found an increase in breast cancer rate with increasing intake.