Salicylic acid in the serum of subjects not taking aspirin. Comparison of salicylic acid concentrations in the serum of vegetarians, non-vegetarians, and patients taking low dose aspirin.

AIMS: To determine serum salicylic acid concentrations in non-vegetarians and vegetarians not taking salicylate drugs, and to compare these concentrations with those found in patients taking aspirin, 75 mg daily. METHODS: Serum samples were obtained from vegetarians (n = 37) and non-vegetarians (n = 39) not taking salicylate drugs. Non-vegetarians and vegetarians were recruited from the community and from a Buddhist monastery, respectively, in Dumfries and Galloway, Scotland. Patients (n = 14) taking aspirin (75 mg daily) were recruited from the Dumfries diabetic clinic. Serum salicylic acid concentrations were determined using a high performance liquid chromatography method with electrochemical detection. RESULTS: Salicylic acid was detected in every serum sample analysed. Higher serum concentrations of salicylic acid were found in vegetarians than non-vegetarians: median concentrations of 0.11 (range, 0.04-2.47) micromol/litre and 0.07 (range, 0.02-0.20) micromol/litre, respectively; the median of the difference was 0.05 micromol/litre (95% confidence interval for difference, 0.03 to 0.08; p < 0.0001). The median serum concentration of salicylic acid in patients taking aspirin (75 mg daily) was 10.03 (range, 0.23-25.40) micromol/litre, which was significantly higher than that found in non-vegetarians and vegetarians. There was overlap in serum salicylic acid concentrations between the vegetarians and patients taking aspirin. CONCLUSIONS: Salicylic acid, a non-steroidal anti-inflammatory drug, is present in fruits and vegetables and is found in higher concentrations in vegetarians than non-vegetarians. This suggests that a diet rich in fruits and vegetables contributes to the presence of salicylic acid in vivo. There is overlap between the serum concentrations of salicylic acid in vegetarians and patients taking aspirin, 75 mg daily. These findings may explain, in part, the health promoting effects of dietary fruits and vegetables.

Comparison of the phenolic composition of fruit juices by single step gradient HPLC analysis of multiple components versus multiple chromatographic runs optimised for individual families.

After minimal sample preparation, two different HPLC methodologies, one based on a single gradient reversed-phase HPLC step, the other on multiple HPLC runs each optimised for specific components, were used to investigate the composition of flavonoids and phenolic acids in apple and tomato juices. The principal components in apple juice were identified as chlorogenic acid, phloridzin, caffeic acid and p-coumaric acid. Tomato juice was found to contain chlorogenic acid, caffeic acid, p-coumaric acid, naringenin and rutin. The quantitative estimates of the levels of these compounds, obtained with the two HPLC procedures, were very similar, demonstrating that either method can be used to analyse accurately the phenolic components of apple and tomato juices. Chlorogenic acid in tomato juice was the only component not fully resolved in the single run study and the multiple run analysis prior to enzyme treatment. The single run system of analysis is recommended for the initial investigation of plant phenolics and the multiple run approach for analyses where chromatographic resolution requires improvement.

Resting metabolic rate and obesity in childhood acute lymphoblastic leukaemia.

The present study described excess weight gain in children with acute lymphoblastic leukaemia (ALL) treated without cranial radiotherapy, and tested the hypothesis that reduced resting metabolic rate (RMR) predisposes children with ALL to excess weight gain. Changes in relative weight in 35 children were expressed as BMI standard deviation (s.d.) scores from diagnosis to 2 y post diagnosis. RMR was measured by ventilated hood indirect calorimetry in 27 patients who had been in positive energy balance and 27 healthy control children matched pairwise for gender and fat free mass (FFM). Mean change in BMI s.d. score to 2 y was +1.0 (s.d. 1.3), 95% CI +0.5 to +1.5 (paired t, P < 0.01). No significant differences in RMR were observed between patients and controls (paired t-test; analysis of covariance). We conclude that excess weight gain occurs during ALL therapy, even in the absence of cranial radiotherapy. Children with ALL who have been in positive energy balance do not appear to show abnormalities in RMR.