Socio-economic differences in diet, physical activity and leisure-time screen use among Scottish children in 2006 and 2010: are we closing the gap?

OBJECTIVE: To investigate socio-economic differences in children's diet, activity and inactivity and changes in these differences over 4 years during which new policies on food in schools were introduced. DESIGN: Two cross-sectional surveys in which diet was assessed by FFQ and physical activity and inactivity were assessed by interviewer-administered questionnaire. Socio-economic status was assessed by the area-based Scottish Index of Multiple Deprivation. SETTING: Scotland, 2006 and 2010. SUBJECTS: Children aged 3-17 years (n 1700 in 2006, n 1906 in 2010). RESULTS: In both surveys there were significant linear associations between socio-economic deprivation and intakes of energy, non-milk extrinsic sugars (NMES) as a percentage of food energy, sugar-sweetened beverages, confectionery, crisps and savoury snacks and leisure-time screen use (all higher among children in more deprived areas), while intakes of fruit, fruit juice and vegetables showed the opposite trend. In 2010 children in more deprived areas engaged in more physical activity out of school than those in more affluent areas, but between 2006 and 2010 there was an overall reduction in physical activity out of school. There were also small but statistically significant overall reductions in intakes of confectionery, crisps and savoury snacks, energy and NMES and saturated fat as a percentage of food energy, but no statistically significant change in socio-economic gradients in diet or activity between the two surveys. CONCLUSIONS: Interventions to improve diet and physical activity in children in Scotland need to be designed so as to be effective in all socio-economic groups.

Cardiovascular benefits of lycopene: fantasy or reality?

Epidemiological evidence indicates that high consumption of tomatoes and tomato-based products reduces the risk of chronic diseases such as CVD and cancer. Such potential benefits are often ascribed to high concentrations of lycopene present in tomato products. Mainly from the results of in vitro studies, potential biological mechanisms by which carotenoids could protect against heart disease and cancer have been suggested. These include cholesterol reduction, inhibition of oxidation processes, modulation of inflammatory markers, enhanced intercellular communication, inhibition of tumourigenesis and induction of apoptosis, metabolism to retinoids and antiangiogenic effects. However, with regard to CVD, results from intervention studies gave mixed results. Over fifty human intervention trials with lycopene supplements or tomato-based products have been conducted to date, the majority being underpowered. Many showed some beneficial effects but mostly on non-established cardiovascular risk markers such as lipid peroxidation, DNA oxidative damage, platelet activation and inflammatory markers. Only a few studies showed improvement in lipid profiles, C reactive protein and blood pressure. However, recent findings indicate that lycopene could exert cardiovascular protection by lowering HDL-associated inflammation, as well as by modulating HDL functionality towards an antiatherogenic phenotype. Furthermore, in vitro studies indicate that lycopene could modulate T lymphocyte activity, which would also inhibit atherogenic processes and confer cardiovascular protection. These findings also suggest that HDL functionality deserves further consideration as a potential early marker for CVD risk, modifiable by dietary factors such as lycopene.

Food and drink purchasing habits out of school at lunchtime: a national survey of secondary school pupils in Scotland.

BACKGROUND: Food and drink purchasing habits of pupils out of school at lunchtime may be contributing to poor dietary intakes and overweight and obesity. The aim of this study was to identify the places from which purchases were made, types of food and drinks purchased and, the reasons for purchasing food or drinks out of school. METHODS: A survey of the food and drinks purchasing habits of secondary school pupils (11-16 yrs) out of school at lunchtime was conducted in Scotland in 2010. A face-to-face interview and a self-completion questionnaire was designed to identify the food outlets used at lunchtime, types of food and drinks purchased and pupils' reasons for purchasing food or drinks out of school. Height and weight were measured and BMI centiles used to classify pupils as normal weight, overweight or obese. Results were compared by age group, sex, BMI group and level of socio-economic deprivation. RESULTS: Of the 612 pupils who completed the survey, 97 % reported having access to places selling food or drinks out of school at lunchtime, and of these 63 % made purchases. A higher proportion of pupils from more deprived areas reported purchasing food or drinks out of school, but the proportion making purchases did not differ significantly by sex or BMI group. Supermarkets were the outlets from which pupils reported most often making purchases, with fewer purchasing food or drinks from fast food takeaways, and this did not differ significantly by socio-economic deprivation. Reasons for making purchases included availability of preferred food and drinks, some of which are restricted for sale in schools, and social reasons, such as wanting to be with friends. Sandwiches and non-diet soft drinks were items most commonly purchased, followed by confectionery and diet soft drinks. However, less than 10 % of all the secondary school pupils reported purchasing these foods every day. CONCLUSIONS: Supermarkets, not just fast food outlets, should be considered when developing strategies to improve the dietary habits of pupils at lunchtime. The importance of food preferences and social reasons for purchasing food and drinks need to be acknowledged and integrated in future interventions.

Oats and CVD risk markers: a systematic literature review.

High consumption of whole-grain food such as oats is associated with a reduced risk of CVD and type 2 diabetes. The present study aimed to systematically review the literature describing long-term intervention studies that investigated the effects of oats or oat bran on CVD risk factors. The literature search was conducted using Embase, Medline and the Cochrane library, which identified 654 potential articles. Seventy-six articles describing sixty-nine studies met the inclusion criteria. Most studies lacked statistical power to detect a significant effect of oats on any of the risk factors considered: 59 % of studies had less than thirty subjects in the oat intervention group. Out of sixty-four studies that assessed systemic lipid markers, thirty-seven (58 %) and thirty-four (49 %) showed a significant reduction in total cholesterol (2-19 % reduction) and LDL-cholesterol (4-23 % reduction) respectively, mostly in hypercholesterolaemic subjects. Few studies (three and five, respectively) described significant effects on HDL-cholesterol and TAG concentrations. Only three out of twenty-five studies found a reduction in blood pressure after oat consumption. None of the few studies that measured markers of insulin sensitivity and inflammation found any effect after long-term oat consumption. Long-term dietary intake of oats or oat bran has a beneficial effect on blood cholesterol. However, there is no evidence that it favourably modulates insulin sensitivity. It is still unclear whether increased oat consumption significantly affects other risk markers for CVD risk, and comprehensive, adequately powered and controlled intervention trials are required to address this question.

Oats and bowel disease: a systematic literature review.

Whole-grain foods such as oats may protect against colorectal cancer and have benefits on inflammatory bowel disease and coeliac disease. The present study aimed to systematically review the literature describing intervention studies that investigated the effects of oats or oat bran on risk factors for bowel disease. A literature search was conducted using Embase, Medline and the Cochrane library, which identified 654 potential articles. Thirty-eight articles describing twenty-nine studies met the inclusion criteria. Two studies carried out in participants with a history of colorectal adenomas found no effects of increased oat-bran intake on indirect risk makers for colorectal cancer. One of two interventions with oat bran in patients with ulcerative colitis showed small improvements in the patients' conditions. Most of the eleven studies carried out in adults with coeliac disease showed no negative effects of uncontaminated oat consumption. The fourteen studies carried out in volunteers with no history of bowel disease suggest that oats or oat bran can significantly increase stool weight and decrease constipation, but there is a lack of evidence to support a specific effect of oats on bowel function compared with other cereals. A long-term dietary intake of oats or oat bran could benefit inflammatory bowel disorders, but this remains to be proven. A protective effect on colorectal adenoma and cancer incidence has not yet been convincingly shown. The majority of patients with coeliac disease could consume up to 100 g/d of uncontaminated oats, which would increase the acceptability of, and adherence to, a gluten-free diet.

Do health behaviours change after colonoscopy? A prospective cohort study on diet, alcohol, physical activity and smoking among patients and their partners.

OBJECTIVES: To describe diet, alcohol, physical activity and tobacco use prospectively, that is, before and 10 months after colonoscopy for patients and their partners. DESIGN: Prospective cohort study of health behaviour change in patients and partners. Comparison groups are patients receiving a normal result notification (NRN) versus patients receiving an abnormal result notification (ARN). Patients and partners (controls) are also compared. SETTING: 5 Scottish hospitals. PARTICIPANTS: Of 5798 colonoscopy registrations, 2577 (44%) patients met the eligibility criteria of whom 565 (22%) were recruited; 460 partners were also recruited. MEASURES: International Physical Activity Questionnaire, Scottish Collaborative Group Food Frequency Questionnaire (includes alcohol), smoking status, sociodemographic characteristics, body mass index, medical conditions, colonoscopy result, Multidimensional Health Locus of Control Scale, behaviour-specific self-efficacy scales. RESULTS: 57% of patients were men, with a mean age of 60.8 years (SE 0.5) and 43% were from more affluent areas. 72% (n=387) of patients received an ARN and 28% (n=149) received an NRN. Response rate of the second questionnaire was 68.9%. Overall, 27% of patients consumed <5 measures of fruit and vegetables/day, 20% exceeded alcohol limits, 50% had low levels of physical activity and 21% were obese. At 10-month follow-up, a 5% reduction in excessive alcohol consumption and an 8% increase in low levels of physical activity were observed among patients; no significant changes occurred in partners. Baseline high alcohol consumption and low physical activity were the strongest predictors of these behaviours at follow-up. Low alcohol self-efficacy and increasing age were associated with poorer health-related behaviours at follow-up for alcohol consumption and physical activity, respectively. CONCLUSIONS: Colonoscopy is associated with marginal beneficial changes in some behaviours but not others. Further work is needed to explore how services can optimise increases in beneficial behaviours and mitigate increases in harmful ones. REGISTRATIONS: REC REF 10/S0709/24, UKCRN 9911.

Lycopene intervention reduces inflammation and improves HDL functionality in moderately overweight middle-aged individuals.

The management of overweight subjects by interventions aimed at reducing inflammation is highly desirable. To date, observational studies have identified a link between increased dietary antioxidant intake and reduced cardiovascular morbidity. However, direct trial evidence regarding the ability of antioxidants to influence inflammation is lacking. Therefore, this study examined lycopene's ability to lower systemic and high-density lipoprotein (HDL)-associated inflammation in moderately overweight middle-aged subjects. Serum was collected before and after a 12-week intervention from 54 moderately overweight, middle-aged individuals. Subjects were randomised to one of three groups: control diet (<10 mg lycopene/week), lycopene-rich diet (224-350 mg lycopene/week) and lycopene supplement (70 mg lycopene/week). HDL was subfractionated into HDL(2&3) by rapid ultracentrifugation. Compliance was monitored by assessing lycopene concentration in serum and HDL(2&3). Systemic and HDL-associated inflammation was assessed by measuring serum amyloid A (SAA) levels. HDL functionality was determined by monitoring the activities of paraoxonase-1 (PON-1), cholesteryl ester transfer protein (CETP) and lecithin cholesterol acyltransferase (LCAT). Lycopene increased in serum and HDL(2&3) following both lycopene interventions (P<.001, for all), while SAA decreased in serum following the lycopene supplement and in HDL(3) following both lycopene interventions (P<.05 for all). PON-1 activity increased in serum and HDL(2&3) in both lycopene groups (P<.05, for all). Furthermore, the activity of CETP decreased in serum following the lycopene supplement, while the activity of LCAT increased in serum and HDL(3) following both lycopene interventions (P<.05 for all). These results demonstrate that in moderately overweight, middle-aged subjects, increasing lycopene intake leads to changes to HDL(2&3), which we suggest enhanced their antiatherogenic properties. Overall, these results show the heart-protective properties of increased lycopene intake.

Children's Food and Drink Purchasing Behaviour "Beyond the School Gate": The Development of a Survey Module.

Many children eat a diet which supplies a higher than recommended amount of nonmilk extrinsic sugars and saturated fatty acids. The school setting is often targeted for nutrition intervention as many children consume food at school. In Scotland, attempts have been made to improve the nutritional content of food in schools and attention has now turned to food and drink available "beyond the school gate." This paper describes the development of a module on food and drink purchasing behaviour. The Food Purchasing Module was designed to collect data, for the first time, from a representative sample of children aged 8-16 years about food and drinks purchased on the way to/from school, during break time/free periods, and at lunchtime, from outlets around schools. Cognitive testing of the module highlighted that younger children find self-completion questionnaires problematic. Older children have fewer problems with self-completion questionnaires but many do not follow question routing, which has implications for the delivery of future surveys. Development of this survey module adds much needed evidence about effectively involving children in surveys. Further research exploring food and drinks purchased beyond the school gate is needed to continue to improve the nutritional quality of children's diets.

Effect of a tomato-rich diet on markers of cardiovascular disease risk in moderately overweight, disease-free, middle-aged adults: a randomized controlled trial.

BACKGROUND: Cardiovascular disease (CVD) is a major cause of mortality in the United Kingdom. Epidemiologic studies suggest that consumption of tomato-based foods may lower CVD risk. Such potential benefits have been ascribed in part to high concentrations of lycopene in the tomatoes. However, these findings have not yet been validated by comprehensive intervention trials. OBJECTIVE: The aim of this study was to conduct a single-blind, randomized controlled intervention trial with healthy middle-aged volunteers to assess whether the consumption of tomato-based foods affects recognized biomarkers of CVD risk. DESIGN: After a 4-wk run-in period with a low-tomato diet, 225 volunteers (94 men and 131 women) aged 40-65 y were randomly assigned into 1 of 3 dietary intervention groups and asked to consume a control diet (low in tomato-based foods), a high-tomato-based diet, or a control diet supplemented with lycopene capsules (10 mg/d) for 12 wk. Blood samples were collected at baseline, at 6 wk, and after the intervention and were analyzed for carotenoid and lipid profiles and inflammatory markers. Blood pressure, weight, and arterial stiffness were also measured. Dietary intake was also determined during the intervention. RESULTS: None of the systemic markers (inflammatory markers, markers of insulin resistance and sensitivity) changed significantly after the dietary intervention. Moreover, lipid concentrations and arterial stiffness were also unaffected by the interventions. CONCLUSION: These data indicate that a relatively high daily consumption of tomato-based products (equivalent to 32-50 mg lycopene/d) or lycopene supplements (10 mg/d) is ineffective at reducing conventional CVD risk markers in moderately overweight, healthy, middle-aged individuals. This trial was registered at isrctn.org as ISRCTN34203810.

Study protocol: the empirical investigation of methods to correct for measurement error in biobanks with dietary assessment.

BACKGROUND: The Public Population Project in Genomics (P3G) is an organisation that aims to promote collaboration between researchers in the field of population-based genomics. The main objectives of P3G are to encourage collaboration between researchers and biobankers, optimize study design, promote the harmonization of information use in biobanks, and facilitate transfer of knowledge between interested parties. The importance of calibration and harmonisation of methods for environmental exposure assessment to allow pooling of data across studies in the evaluation of gene-environment interactions has been recognised by P3G, which has set up a methodological group on calibration with the aim of; 1) reviewing the published methodological literature on measurement error correction methods with assumptions and methods of implementation; 2) reviewing the evidence available from published nutritional epidemiological studies that have used a calibration approach; 3) disseminating information in the form of a comparison chart on approaches to perform calibration studies and how to obtain correction factors in order to support research groups collaborating within the P3G network that are unfamiliar with the methods employed; 4) with application to the field of nutritional epidemiology, including gene-diet interactions, ultimately developing a inventory of the typical correction factors for various nutrients. METHODS/DESIGN: Systematic review of (a) the methodological literature on methods to correct for measurement error in epidemiological studies; and (b) studies that have been designed primarily to investigate the association between diet and disease and have also corrected for measurement error in dietary intake. DISCUSSION: The conduct of a systematic review of the methodological literature on calibration will facilitate the evaluation of methods to correct for measurement error and the design of calibration studies for the prospective pooling of biobanks. This could increase the efficiency of the design of such studies, improve statistical power, reduce bias, and aid in the assessment of gene-environment interaction effects in complex diseases. The systematic review of calibration of dietary intake information could inform gene-diet interaction investigations involving the pooling of results from studies with nutritional data collected in different ways.

Sugar intake and dental decay: results from a national survey of children in Scotland.

The aim of this analysis was to investigate the strength of the association between sugar intake and treatment for dental decay in children in Scotland, and the impact of tooth brushing frequency on this association. The Survey of Sugar Intake among Children in Scotland was carried out in 2006 in those aged 3-17 years. Diet was assessed using the Scottish Collaborative Group FFQ, and interviews were carried out by trained fieldworkers who asked about dental health. A total of 1700 interviews were carried out, and 1512 FFQ were returned. Of the children, 56% had received treatment for decay (fillings or teeth removed due to decay). Intake of non-milk extrinsic sugars (NMES), but not total sugar, increased the risk of having had treatment for decay: adjusted OR 1.84 (95% CI 1.28, 2.64) for the highest ( ≥ 20.0% food energy) v. lowest ( ≤ 14.8% food energy) tertile of NMES intake. This raised risk remained in children who reported brushing their teeth at least twice a day. Compared with children who reported brushing their teeth at least twice a day and were in the lowest tertile of NMES intake, children who reported brushing their teeth once a day or less and were in the highest tertile of NMES intake were over three times more likely to have received treatment for decay (adjusted OR 3.39, 95% CI 1.97, 5.82). In order to improve dental health in children in Scotland, dental health strategies must continue to stress the importance of both reduced NMES intake and good oral hygiene.

Sugar and fat intake among children in Scotland: what is needed to reach the dietary targets?

OBJECTIVE: To assess the intake and sources of non-milk extrinsic sugars (NMES) and fat among children in Scotland in relation to socio-economic status, and to estimate the changes in diet required to achieve recommended levels of intake. DESIGN: Cross-sectional survey with diet assessed by semi-quantitative FFQ. SETTING: Eighty postcode sectors across Scotland. SUBJECTS: Children (n 1398) aged 3-17 years recruited from the Child Benefit register (76 % of those contacted). RESULTS: The mean intake of NMES of 17.4 (95 % CI 17.0, 17.8) % food energy was considerably higher than the UK recommended population average of 11 % food energy. The mean intake of total fat of 32.9 (95 % CI 32.7, 33.2) % food energy met the recommended population average of no more than 35 % food energy, while the mean intake of SFA of 13.8 (95 % CI 13.7, 14.0) % food energy was above the recommended population average of no more than 11 % food energy. Despite clear socio-economic gradients in the mean daily consumption of many 'healthy' and 'unhealthy' food groups, socio-economic differences in NMES as a percentage of food energy were limited and there was no significant variation in the intake of total fat or SFA as a percentage of food energy with socio-economic status. Modelling of the data showed that removing sugar-sweetened soft drinks and increasing fruit and vegetable intake by 50 % would not restore the intake of NMES and SFA to recommended levels. CONCLUSIONS: Major changes in the intake of many food groups will be required to bring the NMES and saturated fat intake in line with current dietary recommendations.

Dietary patterns of school-age children in Scotland: association with socio-economic indicators, physical activity and obesity.

The Survey of Sugar Intake among Children in Scotland was carried out in May to September 2006. The present study aimed to identify dietary patterns in school-aged children from the survey and investigate associations with socio-economic factors, obesity and physical activity. Habitual diet was assessed using the Scottish Collaborative Group FFQ. Height and weight were measured by trained fieldworkers. A total of 1233 FFQ were available for analysis. Dietary patterns were identified by age (5-11 and 12-17 years) and sex using principal components analysis. Associations between factor scores and socio-economic status, education level of the main food provider, physical activity levels and BMI category (based on UK 1990 charts) were examined. Three dietary patterns were identified in each age and sex group. 'Healthier' patterns loading highly for fruit and vegetables were significantly associated with higher socio-economic status and higher education levels of the main food provider whereas more 'unhealthy' patterns ('snacks' and 'puddings') were associated with lower socio-economic status and lower education levels of the main food provider. There was no consistent association between dietary patterns and BMI group or time spent in physical activity. However, inactivity (screen time) was inversely associated with 'healthier' patterns in all age and sex groups and positively associated with 'puddings' and 'snacks' in girls aged 5-11 years. Clear dietary patterns can be identified in school-age children in Scotland, which are consistently related to socio-economic factors and inactivity. This has implications for targeting health promotion at subgroups in terms of lifestyle changes required.

A novel online Food Recall Checklist for use in an undergraduate student population: a comparison with diet diaries.

BACKGROUND: University students are commonly overlooked when diet of populations is measured and there is a lack of comprehensive dietary assessment in whole university student populations. To measure diet of undergraduate students, a new online 121-item Food Recall Checklist (FoRC) was designed as an alternative to a non-weighed record (food diary). This article reports the comparison between the new dietary assessment method (FoRC) and the food diary as a measure of energy (kJ), fat (g), Non-Starch Polysaccharide (NSP) (g), fruit and vegetables (g), breakfast cereal (g) and bread (g) and alcohol (units) intake. METHODS: Fifty-three students at the University of Aberdeen completed four days of FoRC then four days food diary. Median agreement and correlation between the two methods was assessed for foods and nutrients using the Spearman's rank correlation co-efficient and the Wilcoxon signed ranks test. Agreement between FoRC and food diary was assessed using the Bland-Altman method. RESULTS: The mean time taken to complete FoRC for one day was 7.4 minutes. Intakes of fat (g and % food energy), NSP and bread were similar between FoRC and the food diary. Median energy intake was 8185 kJ in the food diary and 8007 kJ in FoRC. However, FoRC recorded significantly lower intakes of energy and alcohol and significantly higher intakes of fruit and vegetables and breakfast cereal compared with the food diary. There was considerable variation in agreement between methods at the individual level. For all variables except alcohol and percentage energy from fat, correlation co-efficients were statistically significant and greater than 0.5. CONCLUSION: At the group level, four days of FoRC showed good median agreement with the food diary and there was high correlation between methods for most foods and nutrients. This suggests that this novel method of assessing diet can provide a useful alternative for assessing group mean intakes but that individual intakes may need to be interpreted with care.

Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene, intakes of folate and related B vitamins and colorectal cancer: a case-control study in a population with relatively low folate intake.

Folate is key in one-carbon metabolism, disruption of which can interfere with DNA synthesis, repair, and methylation. Efficient one-carbon metabolism requires other B vitamins and the optimal activity of enzymes including 5,10-methylenetetrahydrofolate reductase (MTHFR). We report a population-based case-control study of folate intake, related dietary factors and MTHFR polymorphisms (C677T, A1298C) and colorectal cancer in a population with relatively high colorectal cancer incidence and relatively low folate intake. A total of 264 cases with histologically confirmed incident colorectal cancer and 408 controls participated. There was no clear trend in risk with reported intakes of total, or dietary, folate, riboflavin, vitamin B12 or vitamin B6, nor were there interactions between folate intake and the other B vitamins or alcohol. For C677T, risk decreased with increasing variant alleles (multivariate OR for CT v. CC = 0.77 (95 % CI 0.52, 1.16); OR for TT v. CC = 0.62 (95 % CI 0.31, 1.24)), which, although not statistically significant, was consistent with previous studies. For A1298C, compared with AA subjects, CC subjects had modest, non-significant, reduced risk (multivariate OR = 0.81 (95 % CI 0.45, 1.49)). There were significant interactions between total folate and C677T (P = 0.029) and A1298C (P = 0.025), and total vitamin B6 and both polymorphisms (C677T, P = 0.016; A1298C, P = 0.033), although the patterns observed differed from previous studies. Seen against the setting of low folate intake, the results suggest that the role of folate metabolism in colorectal cancer aetiology may be more complex than previously thought. Investigation of particular folate vitamers (for example, tetrahydrofolate, 5,10-methylenetetrahydrofolate) may help clarify carcinogenesis pathways.

Information recovery in cancer families: value for risk estimations.

BACKGROUND: Drawing an informative pedigree is fundamental in genetic counselling. It is very common for some parts of pedigrees to remain ambiguous because of the proband's inability to recall the past history of her/his family. Current age, date of birth, date of death and age of diagnosis are the commonest missing information in pedigrees. METHODS: The Scottish Social Statistics website, National Statistics website and English language literature were used to model extrapolations. About 172 Grampian families and three high-risk Grampian families with complete information were chosen to evaluate the influence of extrapolations on models' performance. Differences between original data and extrapolated data were assessed by independent samples t-test. RESULTS: Changes made by extrapolations in age- and cancer-related information were not statistically significant (P > 0.05) in comparison with original data, except for average age of diagnosis of breast cancer (P = 0.03). The differences made by extrapolations in estimated probabilities generated by probability assessment models were small and ignorable except that for Tyrer-Cuzick model for Grampian family 3. CONCLUSION: Extrapolations based on National Health Statistics can scientifically cover missing information in a defined population with minimum effect on performance of probability assessment models.

Colorectal cancer and genetic polymorphisms of CYP1A1, GSTM1 and GSTT1: a case-control study in the Grampian region of Scotland.

Cytochrome P-450 CYP1A1 is involved in the metabolism of polycyclic aromatic hydrocarbons (PAHs) that are derived from meat intake and tobacco smoking. Expression of the CYP1A1 gene is induced by compounds present in cruciferous vegetables. The glutathione S-transferases play a central role in the detoxification of carcinogens, including PAHs. We investigated the association between colorectal cancer and three variants (CYP1A1*2A, CYP1A1*2C, CYP1A1*4) of the CYP1A1 gene, and homozygosity for the null deletion of the GSTM1 and GSTT1 genes, and the joint effects of these genotypes and smoking, meat intake and intake of green leafy vegetables in a population-based study of 264 cases and 408 controls in Northeast Scotland. There was an inverse association with the CYP1A1*4 (m4) variant (OR 0.3, 95% CI 0.13-0.70). The OR for the CYP1A1*2C (m2) variant was 1.3 (95% CI 0.59-2.91), which is similar to a combined estimate for previous studies (OR 1.2, 95% CI 0.95-1.41). We observed no association with the CYP1A1*2A (m1) variant, or the GSTM1 and GSTT1 polymorphisms. Significant interactions between all 3 CYP1A1 variants and meat intake, and between the m1 and m2 variants and intake of green leafy vegetables, were observed. There was no evidence of interaction between CYP1A1 and smoking, and no evidence of interaction between the GSTM1 or GSTT1 polymorphisms and smoking, meat intake, green leafy vegetable intake, CYP1A1 variants or each other.

The effect of genetic variation on the lipid response to dietary change: recent findings.

PURPOSE OF REVIEW: Dyslipidaemia is an important risk factor for cardiovascular disease, and can be modified by diet. However, the lipid response to dietary change may be influenced by genetic variation. This review examines recent research (published since August 2003) on the effect of genetic variation on the lipid response to dietary change. RECENT FINDINGS: In 10 reports describing intervention studies and seven reports describing observational studies, the lipid response to diet was modified by polymorphisms within the genes for apoE, apoB, apoCIII, lipoprotein lipase, hepatic lipase, endothelial lipase, the liver fatty acid-binding protein, the beta3-adrenergic receptor, adipsin and the peroxisome proliferator-activated receptor gamma. The studies varied widely in terms of the number and type of study participants, the composition and duration of the dietary interventions, the nutrients studied and dietary assessment methods used in the observational studies, and the polymorphisms analysed--some of which had not been studied before with regard to the lipid response to diet. SUMMARY: The lipid response to dietary change is highly complex. Future studies will have to be large in order to assess the effects of multiple polymorphisms, and will have to control for many factors other than diet. At present, it is premature to recommend the use of genotyping in the design of therapeutic diets. However, such studies may be useful in identifying the mechanisms by which dietary components influence lipid levels.