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Alan Garton and his group at The Rowett Research Institute in Aberdeen made very significant and unique contributions to the understanding of differences in digestion, absorption and metabolism of dietary lipids (fats) and their importance to health in mammalian species, particularly farm animals, but also various aspects of lipid metabolism and health in humans. The group were the first to use commercially available gas chromatography and first, this side of the Atlantic, to employ thin-layer chromatography for lipid analyses. A special adaptation of radio-gas chromatography, developed in-house, also led to the definitive evidence that radio-labelled methylmalonyl-CoA, derived from propionic acid, particularly from grain-fed sheep, can be utilized for fatty acid synthesis. Alan always highlighted the relevance of the group's lipid research to human health and wellbeing, as seen by the role of branched-chain fatty acids in Refsum's disease and the later development of studies of the role of saturated and essential omega-3, -6 and -9 fatty acids, including conjugated linoleic acids and trans fatty acids, in human health and disease by the group.

Background: Three daily portions of whole-grain foods could lower cardiovascular disease risk, but a comprehensive intervention trial was needed to confirm this recommendation. Objectives: We aimed to assess the effects of consumption of 3 daily portions of whole-grain foods (provided as only wheat or a mixture of wheat and oats) on markers of cardiovascular disease risk in relatively high-risk individuals. Design: This was a randomized controlled dietary trial in middle-aged healthy individuals. After a 4-wk run-in period with a refined diet, we randomly allocated volunteers to a control (refined diet), wheat, or wheat + oats group for 12 wk. The primary outcome was a reduction of cardiovascular disease risk factors by dietary intervention with whole grains, which included lipid and inflammatory marker concentrations, insulin sensitivity, and blood pressure. Results: We recruited a total of 233 volunteers; 24 volunteers withdrew, and 3 volunteers were excluded. Systolic blood pressure and pulse pressure were significantly reduced by 6 and 3 mm Hg, respectively, in the whole-grain foods groups compared with the control group. Systemic markers of cardiovascular disease risk remained unchanged apart from cholesterol concentrations, which decreased slightly but significantly in the refined group. Conclusions: Daily consumption of 3 portions of whole-grain foods can significantly reduce cardiovascular disease risk in middle-aged people mainly through blood pressure--lowering mechanisms. The observed decrease in systolic blood pressure could decrease the incidence of coronary artery disease and stroke by [greater than or equal to] 15% and 25%, respectively. This trial was registered at clinicaltrials.gov as ISRCTN27657880. Am J Clin Nutr 2010;92:73340. doi: 10.3945/ajcn.2010.29417.

Background: Evidence for an inverse relation between dietary intake of n-3 polyunsaturated fatty acids (PUFAs) and age-related cognitive decline is inconsistent. This inconsistency may arise because the relation is present only in the absence of the apolipoprotein E [epsilon]4 (APOE [epsilon]4) allele. Objective: We aimed to determine the contribution of erythrocyte n-3 PUFA content to cognitive aging in the presence or absence of the APOE [epsilon]4 allele. Design: We followed up 120 volunteers, born in 1936, at approximate ages of 64, 66, and 68 y. Their intelligence quotient at 11 y old was available. At first follow-up, we determined APOE genotype and measured the PUFA composition of erythrocyte membranes. Six cognitive tests were administered at all follow-ups. We related cognitive performance at [approximately equal to] 64 y old and cognitive changes from [approximately equal to] 64 to [approximately equal to] 68 y old to erythrocyte n-3 PUFA composition on recruitment and to APOE [epsilon]4 allele status. Results: Total n-3 PUFA and docosohexaenoic acid concentrations were associated with benefits for cognition at [approximately equal to] 64 y old and from [approximatey equal to] 64 to [approximatey equal to]68 y old. After adjustment for sex, APOE [epsilon]4 status, and intelligence quotient at 11 y old, the effects associated with total n-3 PUFA remained significant. Cognitive benefits were associated with higher erythrocyte n-3 PUFA content but were significant only in the absence of the APOE [apsilon]4 allele. Conclusions: These data are evidence of a gene x environment interaction for cognitive aging. They are relevant to the analysis of trials of n-3 PUFA supplements in cognitive aging and dementia prevention, and they support heterogeneity in cognitive aging and, possibly, in Alzheimer disease. KEY WORDS Polyunsaturated fatty acids, erythrocytes, cognitive decline, fish-oil consumption, apolipoprotein E, childhood intelligence, cognitive tests

Background: Food supplement use is widely promoted, but little is known about the cognitive effects of food supplements. Objective: We examined the effects of food supplement use on cognitive aging. Design: This was an observational study of subjects born in 1936 whose mental ability was tested in 1947 and who were followed up in 2000-2001, at which time cognition, diet, food supplement use, and risk factors for vascular disease were assessed. In a nested case-control study, fish-oil users were matched with nonusers, and cognitive function was related to erythrocyte n-3 fatty acid composition. Results: Childhood intelligence quotient (IQ) did not differ significantly by category of food supplement use (ie, none, fish oil, vitamins, and other). At the age of 64 y, cognitive function was higher in food supplement users than in nonusers before adjustment for childhood IQ. After adjustment for childhood IQ, digit symbol (mental speed) test scores were higher in food supplement users. Fish-oil supplement users consumed more vitamin C and vegetable and cereal fiber than did non-supplement-users. In a nested case-control study, erythrocyte membrane n-3 content was higher in fish-oil supplement users than in nonusers, but cognitive function did not differ significantly between groups. Total erythrocyte n-3 fatty acids and the ratio of docosahexaenoic acid to arachidonic acid was associated with better cognitive function in late life before and after adjustment for childhood IQ. Conclusions: Food supplement use and erythrocyte n-3 content are associated with better cognitive aging. If associations with n-3 content are causal, optimization of n-3 and n-6 fatty acid intakes could improve retention of cognitive function in old age. KEY WORDS Childhood intelligence, aging, cognition, food supplement, diet, erythrocyte, n-3 polyunsaturated fatty acids