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.

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.

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.

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.

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.

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.