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Hyperhomocysteinemia is a risk factor for atherosclerosis and thrombosis and is inversely related to plasma folate and vitamin B12 levels. We assessed the effects of vitamin supplementation on plasma homocysteine levels in 89 patients with a history of recurrent venous thrombosis and 227 healthy volunteers. Patients and hyperhomocysteinemic (homocysteine level >16 micromol/L) volunteers were randomized to placebo or high-dose multivitamin supplements containing 5 mg folic acid, 0.4 mg hydroxycobalamin, and 50 mg pyridoxine. A subgroup of volunteers without hyperhomocysteinemia was also randomized into three additional regimens of 5 mg folic acid, 0.5 mg folic acid, or 0.4 mg hydroxycobalamin. Before and after the intervention period, blood samples were taken for measurements of homocysteine, folate, cobalamin, and pyridoxal-5'-phosphate levels. Supplementation with high-dose multivitamin preparations normalized plasma homocysteine levels (< or = 16 micromol/L) in 26 of 30 individuals compared with 7 of 30 in the placebo group. Also in normohomocysteinemic subjects, multivitamin supplementation strongly reduced homocysteine levels (median reduction, 30%; range, -22% to 55%). In this subgroup the effect of folic acid alone was similar to that of multivitamin: median reduction, 26%; range, -2% to 52% for 5 mg folic acid and 25%; range, -54% to 40% for 0.5 mg folic acid. Cobalamin supplementation had only a slight effect on homocysteine lowering (median reduction, 10%; range, -21% to 41%). Our study shows that combined vitamin supplementation reduces homocysteine levels effectively in patients with venous thrombosis and in healthy volunteers, either with or without hyperhomocysteinemia. Even supplementation with 0.5 mg of folic acid led to a substantial reduction of blood homocysteine levels.

Objectives: To evaluate possible inconsistencies between recommended, actual and desired folate intake in European adult populations., Design: Review of dietary recommendations, of food consumption surveys, and of intervention and observational studies relating folate intake to the risk of neural tube defects and plasma homocysteine levels., Results: In Europe, mean dietary folate intake in adults is 291 micrograms/d (range 197-326) for men and 247 micrograms/d (range 168-320) for women. The recommended intakes vary between 200-300 micrograms/d (men) and 170-300 micrograms/d (women). However, women with a previous pregnancy affected by a neural tube defect (NTD), are recommended to take 4000 micrograms/d of supplemental folic acid when planning a subsequent pregnancy. For those without a history of NTD, the use of 400 micrograms/d of supplemental folic acid is the best option to prevent the occurrence of NTDs. A daily dose of 650 micrograms supplemental folic acid normalises elevated plasma homocysteine levels, which is a risk factor for cardiovascular diseases. A dietary folate intake of at least 350 micrograms/d is desired to prevent an increase in plasma homocysteine levels of the adult population in general., Conclusions: Mean dietary folate intake in Europe is in line with recommendations, but the desired dietary intake of > 350 micrograms/d is only reached by a small part of studied European populations. It is considered unethical to investigate whether supplements with a dose lower than 400 micrograms/d of folic acid are also protective against NTDs. However, research to establish the lowest effective dose of dietary folate/supplemental folic acid to optimise homocysteine levels and research on the bioavailability of folate is required. This will enable the choice of a strategy to achieve desired folate intakes in the general population. In the meantime, consumption of plant foods like vegetables, fruits, and cereals should be stimulated to reach the desired level of 350 micrograms of dietary folate per day.

The methionine loading test is used for the diagnosis of impaired methionine/homocysteine metabolism, in particular the transsulfuration pathway. Usually this test is performed on a low protein diet to control the intake of methionine. However, this is inconvenient and relatively expensive. In this study we compared the effects of a low protein diet and a standard diet on methionine loading test in 28 subjects (crossover design). The mean difference in homocysteine concentration after methionine loading between the two diets was 1.3 [confidence interval (CI) 95%-1.0-3.6] mumol/L which demonstrates that a special low protein diet is not essential in the performance of the methionine loading test. We also observed that 3 weeks after the first methionine loading test, fasting serum concentration of folate was higher and vitamin B12 concentration was lower.

The effect of dietary fructose vs glucose on iron status was studied in rats. Female rats were fed for 4 wk diets containing either fructose or glucose (709.4 g monosaccharide/kg). Fructose vs glucose lowered iron concentrations in liver, kidney, and heart, but did not alter absolute iron contents.

Developing countries face the problem of an increasing fuelwood shortage. For rural households, fuelwood is the main source of energy. As energy is essential to make food suitable for human consumption by means of cooking, the present fuelwood crisis could jeopardize the nutritional situation of rural households. This article reviews and analyses available data and information on the relationship between the availability of fuelwood and the nutritional situation of rural households. Based on analysis of emperical studies, three main strategies evolved by rural households, especially by the women within these households, to cope with a shortage of fuelwood can be distinguished: (i) increase in time and energy spent on fuelwood collection, (ii) substitution of fuelwood by alternative fuels and (iii) economizing on the consumption of fuelwood and alternative fuels. These coping-strategies affect food supply, food preservation, preparation and distribution, income generating activities and food consumption, all of which result in a decrease in quality and quantity of food consumed and in a deterioration of physical condition, especially women and their young children. Available data on fuelwood availability and nutrition are rather diffuse and incomplete. The presence of several confounding variables in the studies analysed make it difficult to establish the nutritional impact of a growing shortage of fuelwood. Nevertheless, it is concluded that a shortage of fuelwood plays at least an important role in changes in nutritional situation of rural households. If current trends continue, this role will become more important and evident. The impact of a growing fuelwood shortage should be a point of concern for rural development.

A survey was done to register the prevalence of dental fluorosis among children aged 7-16 years and the occurrence of skeletal fluorosis among adults aged 40-60 years living in regions in Senegal where fluoride concentrations in the drinking water ranged from less than 0.1 mg/l to 7.4 mg/l. In the area where the fluoride concentration in the drinking water was 1.1 mg/l milder forms of dental fluorosis were found, the prevalence being 68.5%. In areas where fluoride concentrations exceeded 4 mg/l the prevalence of dental fluorosis reached 100%. Kyphosis was very prevalent in a community whose drinking water contained 7.4 mg/l fluoride. Radiographs of the vertebral column, hand and wrist of 3 adults with kyphosis confirmed the diagnosis of skeletal fluorosis. High sweat loss and a high intake of water because of the hot weather may account for the present findings. The World Health Organisation guidelines for the fluoride concentration in drinking water seems unsuitable for countries with a hot, dry climate.

A survey was done of the prevalence of dental fluorosis among children aged 7-16 years and the occurrence of skeletal fluorosis among adults aged 40-60 years living in regions in Senegal where fluoride concentrations in the drinking water ranged from less than 0.1 to 7.4 mg/l. In the area where the fluoride concentration in the drinking water was 1.1 mg/l milder forms of dental fluorosis were found, the prevalence being 68.5%. In areas where fluoride concentrations exceeded 4 mg/l the prevalence of dental fluorosis reached 100%. Kyphosis was very prevalent among a community whose drinking water contained 7.4 mg/l fluoride. Radiographs of the vertebral column, hand, and wrist of 3 adults with kyphosis confirmed the diagnosis of skeletal fluorosis. High sweat loss and a high intake of water because of the hot weather may account for the finding. The present World Health Organisation guideline for the upper limit of fluoride concentration in drinking water may be unsuitable for countries with a hot, dry climate.