Association of fish and long-chain n-3 polyunsaturated fatty acid intakes with the occurrence of depressive episodes in middle-aged French men and women.

This study aimed to seek whether habitual fish and seafood or n-3 long-chain PUFA intake could influence the occurrence of depressive episodes. In a subsample from the French SU.VI.MAX cohort, dietary habits have been assessed during the first 2 years of the follow-up (six 24-h records) and declarations of antidepressant prescription, taken as markers of depressive episodes, have been recorded during the 8-year follow-up. Subjects consuming fatty fish or with an intake of long-chain n-3 PUFA higher than 0.10% of energy intake had a significantly lesser risk of any depressive episode and of recurrent depressive episodes, but not of single depressive episode. These associations were stronger in men and in non-smokers. In contrast, smokers eating fatty fish had an increased risk of recurrent depression. These results suggest that a usual intake of fatty fish or long-chain n-3 PUFA may decrease the risk of recurrent depression in non-smokers.

Association of folate intake with the occurrence of depressive episodes in middle-aged French men and women.

A low folate intake or a low folate status have been found to be associated with a higher frequency of depression in populations, but the existence and the direction of a causal link between folate intake or status and depression is still uncertain. The aim of this study was to seek the relation between the habitual folate intake in middle-aged men and women and the occurrence of depressive episodes. In a subsample of 1864 subjects (809 men and 1055 women) from the French SU.VI.MAX cohort, dietary habits have been measured at the beginning of the follow-up (six 24 h records) and declarations of antidepressant prescription, taken as markers of depressive episodes, have been recorded during the 8-year follow-up. No significant association was observed between folate intake and the risk of any depressive episode or of a single depressive episode during the follow-up, in both men and women. In contrast, the risk of experiencing recurrent depressive episodes (two or more) during the follow-up was strongly reduced in men with high folate intake (OR 0.25 (95 % CI 0.06, 0.98) for the highest tertile v. the lowest, P for trend 0.046). This association was not observed in women. These results suggest that a low folate intake may increase the risk of recurrent depression in men.

Intake of added oils and fats among middle-aged French adults: relationships with educational level and region of residence.

OBJECTIVE: To describe the relative contribution of 10 created food groups to total fat intake in middle-aged subjects. The relationship of added oil and fat intake with region of residence and educational level was also assessed. DESIGN: Cross-sectional study. SUBJECTS/SETTING: Participants of the French Supplémentation en Vitamines et Minéraux Antioxydants study who completed at least six 24-hour dietary records after inclusion into the study (N=6,572). RESULTS: Added oils and fats were the main source of total fat intake. Animal fat and margarine intakes showed a significant inverse association with educational level, whereas oils with monounsaturated fatty acids (MUFA) were positively associated with education level. Animal fat intake was significantly higher in the western and northern parts of France (54.2% and 50.4%) and lower in the Mediterranean Coast (39.0%). A significant inverse gradient was found with oils with polyunsaturated fatty acids or MUFA in the southwest and the Mediterranean Coast compared with the northern part of France. CONCLUSIONS: We showed a north to south gradient for animal fat intake and the opposite for oils with MUFA and polyunsaturated fatty acid in France. This gradient parallels the known disparities for cardiovascular mortality in this country. This should contribute to adapting dietary guidelines for dietary change in a public health perspective.

Dietary intakes and food sources of n-6 and n-3 PUFA in French adult men and women.

The intake of individual n-6 and n-3 PUFA has been estimated in 4,884 adult subjects (2,099 men and 2,785 women), volunteers from the French SU.VI.MAX intervention trial. The food intakes of each subject were recorded in at least ten 24-h record questionnaires completed over a period of 2.5 yr, allowing the estimation of the daily intake of energy; total fat; and linoleic, alpha-linolenic, arachidonic, eicosapentaenoic (EPA), n-3 docosapentaenoic (DPA), and docosahexaenoic (DHA) acids. The mean total fat intake corresponded to 94.1 g/d (36.3% of total energy intake) in men and 73.4 g/d (38.1% of energy) in women. The intake of linoleic acid was 10.6 g/d in men and 8.1 g/d in women, representing 4.2% of energy intake; that of alpha-linolenic acid was 0.94 g/d in men and 0.74 g/d in women, representing 0.37% of energy intake, with a mean linoleic/alpha-linolenic acid ratio of 11.3. The mean intakes of long-chain PUFA were: arachidonic acid, 204 mg/d in men and 152 mg/d in women; EPA, 150 mg/d in men and 118 mg/d in women; DPA, 75 mg/d in men and 56 mg/d in women; DHA, 273 mg/d in men and 226 mg/d in women; long-chain n-3 PUFA, 497 mg/d in men and 400 mg/d in women. Ninety-five percent of the sample consumed less than 0.5% of energy as alpha-linolenic acid, which is well below the current French recommendation for adults (0.8% of energy). In contrast, the mean intakes of long-chain n-6 and n-3 PUFA appear fairly high and fit the current French recommendations (total long-chain PUFA: 500 mg/d in men and 400 mg/d in women; DHA: 120 mg/d in men and 100 mg/d in women). The intakes of alpha-linolenic acid, and to a lesser extent of linoleic acid, were highly correlated with that of lipids. Whereas the main source of linoleic acid was vegetable oils, all food types contributed to alpha-linolenic acid intake, the main ones being animal products (meat, poultry, and dairy products). The main source of EPA and DHA (and of total long-chain n-3 PUFA) was fish and seafood, but the major source of DPA was meat, poultry, and eggs. Fish and seafood consumption showed very large interindividual variations, the low consumers being at risk of insufficient n-3 PUFA intake.

Long-chain n-3 fatty acid levels in baseline serum phospholipids do not predict later occurrence of depressive episodes: a nested case-control study within a cohort of middle-aged French men and women.

The goal of this study was to seek the relations between baseline n-3 PUFA status and the later occurrence of depressive episodes in a French cohort of middle-aged men and women, the SU.VI.MAX study. A nested case-control study was designed within the cohort: cases with at least two depressive episodes during the 8-year follow-up were paired to non-depressed controls, antidepressant prescriptions being taken as markers of depressive episodes. The fatty acid profiles of baseline serum phospholipids have been determined. Results were analyzed using logistic regression and principal component analysis, taking into account depression history and demographic and lifestyle confounders. There was no consistent association of depression risk with any serum fatty acid, and in particular there was no association of depression risk with the long-chain n-3 PUFA eicosapentaenoic, docosapentaenoic and docosahexaenoic acids. This study does not support the hypothesis of a predictive value of n-3 PUFA status for depression in population settings.

[Dietary fatty acids and colorectal and prostate cancers: epidemiological studies]. / Acides gras alimentaires, cancer colorectal et cancer de la prostate: études épidémiologiques.

OBJECTIVE: This study reviews epidemiological works having studied the associations of dietary fatty acids, especially of n-6 or n-3 polyunsaturated fatty acids (PUFA), with the risks of colorectal and prostate cancers. METHODS: The epidemiological studies reviewed were those having tested the association of colorectal and prostate cancer risk with the dietary intake or the blood or adipose tissue levels of fatty acids, especially of n-6 and n-3 PUFA, and with the dietary intake of fish and seafood. RESULTS: Most studies based on a dietary questionnaire did not find any association of the risk of colorectal cancer with the consumption of either total fatty acids or any particular fatty acid, after adjustment for total energy intake had been made. A few studies suggest that trans fatty acid consumption could increase colorectal cancer risk. Most studies based either on a dietary questionnaire or on biomarkers, did not find any association of total, saturated or monounsaturated fatty acid, as well as of linoleic or arachidonic acids, with prostate cancer risk, after adjustment for total energy intake. Most studies failed to find an association of prostate cancer risk with fish or long-chain n-3 PUFA intake, but recent cohort studies did find an inverse association of fish consumption with the risk of the latest stages of prostate cancer. In contrast, alpha-linolenic acid intake was associated with an increase of prostate cancer risk in a majority of epidemiological studies, but other studies did not find this association. This latter point might be of concern, and needs to be clarified by other results, especially those of ongoing prospective studies.

[Dietary fat consumption of the French population and quality of the data on the composition of the major food groups]. / Consommation lipidique de la population française et qualité des données de composition des principaux groupes d'aliments vecteurs.

The validity of estimated association between dietary fat intake and cancer depends both on the methodology of dietary assessment used and on the quality of food composition data. The food composition database of Afssa/Ciqual shows that there is a deficiency in data on fatty acids. In order to identify the priorities for improving the quality of the database, we analysed the data quality of major dietary contributors of fatty acids in the French population. These food contributors, listed according to their contribution to fat intake, have been identified by French national consumption survey Inca. Consumption studies in France show a high dietary fat contribution (37-38% even 40% of total energy) with over-consumption of saturated fatty acids, under-consumption of monounsaturated fat and, to a lesser extent of polyunsaturated fatty acids. Major food contributors of total fat and saturated fatty acids are butter, cheese, meat products, meats, dishes, dressing, cakes and pastry and, only in children, biscuits. Among contributors of monounsaturated fatty acids, vegetable oils and sauces are listed after processed meats before meats, butter, cheese and dishes. Vegetable oils and sauces are the major contributors of polyunsaturated fatty acids before "fatty" potatoes (such as chips...) in adults whereas the opposite was observed in children. Composition tables do not presently allow the identification of contributors of specific fatty acids (omega 3, omega 6, conjugated linoleic acid). If nutritional data of milk products, fats, and oils are reliable because of existing specific tables for these products, there is a need for improving quality of composition data for other major contributors such as: meats, processed meats, fish and dishes such as pizzas, pasteries...

Dietary N-6 and N-3 polyunsaturated fatty acids and prostate cancer risk: a review of epidemiological and experimental evidence.

OBJECTIVE: This study reviews epidemiological and experimental works dealing with the effects of dietary n -6 or n -3 polyunsaturated fatty acids (PUFA) on prostate cancer (PCa) development and PCa risk. METHODS: Systematic literature searches were made using Medline. The epidemiological studies reviewed (ecological, case-control, cohorts, and nested case-control) were those having tested the association of PCa risk with the dietary intake or the blood or adipose tissue levels of PUFA ( n -6 PUFA, n -3 PUFA, long-chain n -3 PUFA, linoleic acid, alpha -linolenic acid, arachidonic acid, eicosapentaenoic acid, docosahexaenoic acid), and with the dietary intake of fish and seafood. Experimental studies dealing with the effects of PUFA on PCa development in animal models or with PCa cell growth in vitro were also reviewed, as well as studies on the mechanisms of the effects of PUFA on PCa. RESULTS: There is no or little evidence of an association of linoleic or arachidonic acids with PCa risk. Most epidemiological studies failed to find an association of PCa risk with fish or long-chain n -3 PUFA intake, but two recent cohort studies did find an inverse association of fish consumption with the risk of the latest stages of PCa. alpha -linolenic acid intake was associated with an increase of PCa risk in a majority of epidemiological studies, but other studies did not find this association. Experimental work in vitro and in vivo, as well as mechanistic studies, support a protective effect of long-chain n -3 PUFA on PCa, but data on the effects of linoleic and alpha -linolenic acids are scarce. CONCLUSIONS: Long-chain n -3 PUFA from fish are possible promising nutrients for the dietary prevention of PCa, but to-date with little epidemiological support. In contrast, studies suggest that alpha -linolenic acid intake might be a risk factor. New work, both epidemiological and experimental, is awaited to clarify these results.

Polyunsaturated fatty acids in the central nervous system: evolution of concepts and nutritional implications throughout life.

Docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (AA, 20:4n-6) are the major polyunsaturated fatty acids in the membranes of brain and retinal cells. Animals specifically deficient in dietary n-3 fatty acids have low DHA content in their membranes, reduced visual acuity and impaired learning ability. Studies on bottle-fed human infants have shown that adding DHA and AA to milk replacer-formulas can bring their concentrations in the infant blood lipids to values as high as those produced by breast-feeding and significantly improves mental development and maturation of visual function. In older subjects, diverse neuropsychiatric and neurodegenerative diseases have been associated to decreased blood levels of n-3 PUFA. Low intakes of fish or of n-3 PUFA in populations have been associated with increased risks of depression and Alzheimer disease, and n-3 PUFA, especially eicosapentaenoic acid (EPA, 20:5n-3), have shown efficacy as adjunctive treatment - and in some cases as the only treatment--in several psychiatric disorders. The mechanisms by which polyunsaturated fatty acids have an impact on neuronal functions will be reviewed: the modulation of membrane biophysical properties, regulation of neurotransmitter release, synthesis of biologically active oxygenated derivatives, and nuclear receptor-mediated transcription of genes responsive to fatty acids or to their derivatives.