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Objective: To determine the relative efficacy in general practice of dietary advice given by a dietitian, a practice nurse, or a diet leaflet alone in reducing total and low density lipoprotein cholesterol concentration., Design: Randomised six month parallel trial., Setting: A general practice in Oxfordshire., Subjects: 2004 subjects aged 35-64 years were screened for hypercholesterolaemia; 163 men and 146 women with a repeat total cholesterol concentration of 6.0-8.5 mmol/l entered the trial., Interventions: Individual advice provided by a dietitian using a diet history, a practice nurse using a structured food frequency questionnaire, or a detailed diet leaflet sent by post. All three groups were advised to limit the energy provided by fat to 30% or less and to increase carbohydrate and dietary fibre., Main Outcome Measures: Concentrations of total cholesterol and low density and high density lipoprotein cholesterol after six months; antioxidant concentration and body mass index., Results: No significant differences were found at the end of the trial between groups in mean concentrations of lipids, lipoproteins, and antioxidants or body mass index. After data were pooled from the three groups, the mean total cholesterol concentration fell by 1.9% (0.13 mmol/l, 95% confidence interval 0.06 to 0.22, P < 0.001) to 7.00 mmol/l, and low density lipoprotein cholesterol also fell. The total carotenoid concentration increased by 53 nmol/l (95% confidence interval 3.0 to 103, P = 0.039)., Conclusions: Dietary advice is equally effective when given by a dietitian, a practice nurse, or a diet leaflet alone but results in only a small reduction in total and low density lipoprotein cholesterol. To obtain a better response more intensive intervention than is normally available in primary care is probably necessary.

Objective: To examine the relation between subjects' level of cardiovascular risk and their beliefs about the harmfulness of their smoking habit, current diet, and level of exercise, together with their stated desire to modify such behaviour., Design: Self administered postal health and life-style questionnaire followed by a structured health check conducted by a nurse., Setting: Five general practices in Luton and Dunstable, Bedfordshire., Subjects: 5803 people aged 35-64 years enrolled in the OXCHECK trial who attended for a health check before 1 March 1992., Main Outcome Measures: Perceived risk to health of lifestyle behaviours, desire to modify behaviour, and a reported serious attempt to modify behaviour in the preceding year., Results: A high proportion of smokers and those who were physically inactive perceived their behaviour to be harmful (1020; (76%; 95% confidence interval 74% to 79%) and 350 (74%; 70% to 78%) respectively) and wished to modify it (1212 (79%; 77% to 81%) and 375 (74%; 71% to 78%) respectively). In contrast, only 289 (45%; 41% to 48%) of obese people and 188 (14%; 12% to 16%) of people with a high dietary fat intake perceived their current diet to be harmful. The more cardiovascular risk factors present, the more likely subjects were to perceive a health risk attached to their diet and lack of exercise (p < 0.01 in both cases) and to want to improve their diet., Conclusion: Awareness of the health risk from smoking and motivation to stop is high. Further efforts are required, however, to educate the public about the risks associated with a high dietary fat intake. Although the health risks of inactivity were widely recognised, motivation to take more exercise needs to be increased.

Objective: To document how often patients with varying cardiovascular risk levels reported receiving lifestyle advice from general practice., Design: Cross sectional descriptive survey by postal questionnaire., Setting: 5 general practices in Bedfordshire., Subjects: 4941 people aged 35-64 years who had consulted a general practitioner at least once during the 12 months before completing the questionnaire and who subsequently attended for a health check as part of the OXCHECK trial., Main Outcome Measures: Report of having received advice from a general practitioner or practice nurse about smoking, alcohol consumption, exercise, or diet during the 12 months before completing the questionnaire. Cardiovascular risk assessed by a nurse during structured health check., Results: The overall reported rate of advice was 27% for smoking, 4.5% for exercise, 12% for diet, and 3% for alcohol consumption. Those with unhealthy behaviour profile or at increased cardiovascular risk received more advice--for example, 47% of smokers with a history of cardiovascular disease received advice on smoking. Among those at increased risk, men were more likely than women to receive advice about exercise (11% v 4%, p = 0.04) and alcohol consumption (10% v 4%, p = 0.007), while women received more advice about weight (17% v 23%, p < 0.001). The rate of receiving advice was unaffected by age, marital status, or social class., Conclusion: The low rate of lifestyle advice reported by patients implies that more preventive advice could be provided in primary care.

Aim: To re-examine the contentious relation between diet and plasma lipids within a population., Design: Cross sectional sample from a large prospective cohort study of people eating different diets in Britain. Blood samples and diet records collected from subjects., Subjects: Volunteers eating one of four distinct diets--namely, vegans, vegetarians, fish eaters who do not eat meat, and meat eaters. 52 Subjects selected from each group., Methods: Examination of the relation between nutritional intake recorded in a four day dietary record and plasma lipid concentrations of subjects measured in blood samples collected previously., Results: After controlling for age, sex, and body mass index, the correlation between plasma total cholesterol and the Keys score (which includes dietary cholesterol and saturated and polyunsaturated fat) was 0.37 (p less than 0.001). The mean saturated fat intake in all groups was low (6-14% of energy), but polyunsaturated fat intake was high, so mean total fat intake was generally above that recommended. A high dietary fibre intake was not associated with high carbohydrate intake. Plasma high density lipoprotein values were not associated with any measure of fat intake, but there was a significant correlation of 0.24 between high density lipoprotein values and alcohol intake., Conclusions: The nature rather than quantity of dietary fat is an important determinant of cholesterol concentrations. Health conscious individuals select a fat modified, rather than a low fat--high carbohydrate diet. National cholesterol lowering dietary advice should be reconsidered.