Nutrition of elderly men living alone. Part 2, Vitamin C and thiamine status.

A dietary survey using the five day record method was carried out on 35 elderly men living alone in the Christchurch area. The mean calculated intake of vitamin C for these men was 31 mg/day. These dietary intakes of vitamin C were significantly correlated with both plasma vitamin C levels and with leucocyte vitamin C levels. Twelve men (34 percent) with lowered dietary intakes of vitamin C were in the range for asymptomatic scurvy. The mean calculated intake of thiamine was 1.05 mg/day. The mean TPP effect was 12.9 percent (n = 27). Dietary intakes of thiamine showed a significant inverse relationship with TPP effect. Eight subjects (23 percent) who too, less than the Australian dietary allowance had an elevated TPP effect. By both dietary and biochemical methods there was evidence of subclinical vitamin C and thiamine deficiencies in more than a quarter of these men.     

Thiamine supplementation mood and cognitive functioning

One hundred and twenty young adult females took either a placebo or 50 mg thiamine, each day for 2 months. Before and after taking the tablets, mood, memory and reaction times were monitored. An improvement in thiamine status was associated with reports of being more clearheaded, composed and energetic. The taking of thiamine had no influence on memory but reaction times were faster following supplementation. These influences took place in subjects whose thiamine status, according to the traditional criterion, was adequate. Received: 4 June 1996 / Final version: 1 August 1996     

Dietary behavior of French men according to alcohol drinking pattern

Relationships of alcohol consumption with diet were studied in 216 French men aged 18-44. The sample was divided on the basis of alcohol intake in the preceding 7 days: controls (less than or equal to 43 g/day), moderate drinkers (44-87 g/day) and heavy drinkers (88-200 g/day). Moderate and heavy drinkers consumed more meat and meat products, bread and toast, dried vegetables and potatoes than controls but fewer nonalcoholic drinks and less milk, yogurt, cooked vegetables, raw and cooked fruits, pastries and confectioneries. Total energy intake was higher in drinkers than in controls but nonalcoholic energy intake was not significantly different; alcohol was simply added to food intake. Moderate and heavy drinkers consumed significantly less carbohydrates but more fat and protein than controls. Vitamins A and C intakes were lower in the moderate and heavy drinkers than in controls but folate and iron intakes were higher. The differences in dietary habits between controls and drinkers were not related to age nor to socioprofessional status since after adjustment for these two parameters the same relationships were still found.     

Failure of vitamin C to affect the pharmacokinetic profile of antipyrine in man.

A possible interaction of vitamin C with the metabolism of drugs which are oxidized (e.g., antipyrine and diphenylhydantion) is indicated from data in animals. The effect of megadoses of vitamin C (300 mg/day to 4800 mg/day) was therefore tested in human volunteers receiving antiprine (single oral dose) or diphenlhydantoin (chronic therapy). The half-life, volume of distribution, and plasma clearance of antipyrine were not affected by vitamin C treatment. Steady-state plasma levels of diphenylhydantoin in two epileptic patients were similar before and during vitamin C (1.2 Gm/day for 18 days) treatment. It is concluded that vitamin C, in commonly used megadoses, has no effect on the metabolism of antipyrine or diphenylhydantoin in men.     

Vitamin C status of elderly men in a residential home.

The vitamin C status of 35 men, over 70 years of age from a residential home has been studied by measuring the plasma and leucocyte vitamin C levels and by assessing the intake of vitamin C. The mean plasma vitamin C level of the group was 16 +/- 15 mumol/l which was significantly lower (P less than 0.005) than that of a similar group of elderly men living alone (26 +/- 20 mumol/l). The mean leucocyte vitamin C levels of the two groups did not differ significantly. Twenty-nine (83 percent) of the institution group had plasma vitamin C levels below 23 mumol/l and 13 men (37 percent) had leucocyte vitamin C levels below 10 microgram/10(8)WBC. The residents who supplemented the institution diet with their own fresh fruit supplies had higher plasma and leucocyte vitamin C levels than the men who did not (P less than 0.01). Some clinical signs possible related to vitamin C deficiency were recorded but these could not later be statistically related to either plasma or leucocyte vitamin C levels. A case is made for vitamin C supplementation of puddings in institutional meals for the elderly.     

Attaining optimal bone status: lessons from the 1997 National Nutrition Survey

AIMS: To examine the adequacy of calcium intake in relation to current recommendations, demographic differences in calcium intake and dietary sources in the New Zealand population. METHODS: 24-hour diet recall and qualitative food frequency data from the 1997 New Zealand National Nutrition Survey (NNS97) were used. RESULTS: No age-gender subgroups had median intakes meeting the latest (1998) US recommendations. Women's median intakes failed to meet even the considerably lower 1990 Australian recommendations. 20% of New Zealanders and one in four women had intakes below the UK Estimated Average Requirements for calcium. Intakes below the UK Lower Reference Nutrient Intake (the level at which the risk of deficiency is virtually 100%) were common (15-20%) among women aged 15-18 years, those living in the most deprived areas or Maori. Milk and milk products were the major sources of the nation's calcium intake. CONCLUSION: Although other factors such as genetics, hormonal status, vitamin D status and exercise influence skeletal health, adequate calcium intakes are important in minimizing bone loss. A reduction in the proportion of New Zealanders with inadequate calcium intakes will most readily be achieved if more people meet the milk products Dietary Guideline (minimum of two servings daily). Health professionals can play an important role in raising perceptions of the benefits of adequate calcium intakes, promoting the milk products Dietary Guideline, and emphasising that lower fat diets can include adequate calcium through use of reduced fat milk products.     

201O年某区城乡居民膳食营养状况的分析

目的了解北京市丰台区居民膳食营养状况,为开展营养改善和合理膳食指导工作提供科学依据。方法采用多阶段分层整群随机抽样的方法,2010年8月至2010年10月在丰台区抽取6个居委会180户居民共计595人,采用连续3天24小时膳食回顾法与调味品称重法相结合的方法进行膳食调查。计算每标准人日营养素摄入量,并与2002年的营养调查资料进行比较分析。结果2010年北京市丰台区居民蛋白质、脂肪,碳水化合物的供能比分别为12．7％,35．4％,51．9％,膳食结构不尽合理;居民每标准人日能量,蛋白质、脂肪摄入量分别为1954．4kcal、61．7g、77．4g,维生素A、硫胺素、核黄素、烟酸、维生素C、维生素E摄入量分别为415.3μgRE、0．8mg、0．8mg、12．8mg、74．3nag和31．5mg,钠、钙、铁和锌摄八量分别为5576．7、409．6、22．1和9．7mg;除维生素E、钠和铁的摄入量达到或超过RNIJAI推荐水平外,其他营养素摄入量均低于推荐水平。膳食营养素摄入状况较2002年有降低趋势。结论丰台区居民宏量营养素供能比例不合理,绝大部分维生素、矿物质摄入不足,应制定相应的干预措施,控制和预防营养相关疾病的发生。     

ACTH induced sodium appetite in the rat.

Subcutaneous injections of long-acting synthetic ACTH (5 U/day) caused a large increase in the intakes of both 0.5 M NaCl and water in rats. By the fifth day of treatment the rats were turning over an amount of sodium approximating their own total body sodium. The mineral appetite was specific for NaCl. Intakes of KCl, MgCl2 and CaCl2 were unchanged. ACTH was ineffective in adrenalectomized rats suggesting that the appetite was dependent on adrenal hormones.     

Determination of thiamine in human plasma and its pharmacokinetics

Summary A sensitive assay for thiamine suitable for clinical use has been developed. It is based on precolumn oxidation of thiamine to thiochrome followed by HPLC-separation and fluorescence detection. The assay is applicable to various biological materials, including human plasma.The minimum amount detectable was 5 fmol, minimum plasma concentration 0.5 nmol/l and minimum sample volume 0.3 ml plasma. Each chromatographic run took 3 min.Inter- and intra-assay relative standard deviations (RSD) were 8.3% and 6.3%, respectively, at a stock plasma concentration of 10.8 nmol/l. At 38.8 nmol/l, interassay RSD was reduced to 3.4%. The recovery of 5 nmol/l added thiamine was 102 (SD±17)%, that of 30 nmol/l was 94±5%.Plasma levels in 91 volunteers ranged from 6.6 to 43 nmol/l, showing a log normal distribution with a median of 11.6 nmol/l.Thiamine kinetics were studied in plasma and urine from 8 men after intravenous and oral doses of 50, 100 and 200 mg thiamine hydrochloride. In all individuals, nonlinear renal elimination kinetics were demonstrated by plotting the fractional amount of thiamine excreted unchanged in urine against the corresponding area under the plasma concentration — time curve.     

Pharmacological alteration of oxygen-induced lung toxicity.

The effect of eight selected drugs on oxygen-induced pulmonary injury was evaluated in the rat. Several drug treatments, including meclofenamate (5 mg/kg/day), aminophylline (15 mg/kg/day), and vitamin C (20 and 50 mg/kg/every 12 hr) were found not to alter the survival of rats in 96 to 98% oxygen. Although vitamin E deficiency has repeatedly been shown to aggravate oxygen toxicity, pharmacologic doses of vitamin E (20 and 50 mg/kg/every 12 hr) in animals maintained on a normal diet did not offer protection against oxygen-induced lung toxicity. For the remaining drug treatments, the activity of pulmonary antioxidant defense systems [superoxide dimutase (SOD), catalase (CA), glutathione peroxidase (GP), and reduced glutathione (GSH)] were analyzed to explore the possible mechanism of pharmacological alteration of oxygen toxicity. Lungs from rats treated with dexamethasone (0.4 mg/kg/day) were found to have greater oxygen-induced lung damage and significantly lower pulmonary antioxidant activity. Rats pretreated with propylthiouracil (10 mg/kg/day) showed less oxygen-induced lung damage and greater pulmonary GSH levels and CA activity. Indomethacin pretreatment did not affect the course of oxygen toxicity or the activity of pulmonary antioxidant defense systems. GSH levels were lower in lungs of rats pretreated with levothyroxine (16.7 mg/kg/day), which produced an accelerated development of pulmonary oxygen toxicity. It was concluded that modification of the activity of the pulmonary antioxidant defense systems provides a plausible mechanism in explaining pharmacological alteration of oxygen-induced pulmonary injury.     

Effects of oral vitamin K on S- and R-warfarin pharmacokinetics and pharmacodynamics: enhanced safety of warfarin as a CYP2C9 probe.

Evidence for the selectivity of S-warfarin metabolism by CYP2C9 is substantial, suggesting that warfarin may be a potential CYP2C9 phenotyping probe. It is, however, limited by its ability to elevate the international normalized ratio (INR) and potentially cause bleeding. The effect of vitamin K to attenuate the elevation of INR may enable the safe use of warfarin as a probe. The objective of this study was to investigate the pharmacokinetics and pharmacodynamics of S- and R-warfarin in plasma following the administration of warfarin alone versus warfarin and vitamin K in CYP2C9*1 homozygotes. Healthy adults received, in a randomized crossover fashion in a fasted state, warfarin 10 mg orally or warfarin 10 mg plus vitamin K 10 mg orally. Blood samples were obtained over 5 days during each phase. INR measurements were obtained at baseline and day 2 in each phase. INR, AUC0-infinity, and t1/2 of plasma S- and R-warfarin were examined. Eleven CYP2C9*1 homozygotes (3 men, 8 women) were enrolled. INR at day 2 following warfarin 10 mg was 1.18 +/- 0.19, which differed significantly from baseline (INR = 1.00 +/- 0.05) and warfarin with vitamin K (INR = 1.06 +/- 0.07). INR at baseline was not significantly different from warfarin with vitamin K. t1/2 and AUC0-infinity of both enantiomers did not significantly differ between the phases. It was concluded that INR is apparently attenuated by concomitant administration of a single dose of vitamin K without affecting the pharmacokinetics of either warfarin stereoisomer. Warfarin 10 mg may be safely used as a CYP2C9 probe in *1 homozygotes when given concomitantly with 10 mg of oral vitamin K.     

Effect of high-dose vitamin C on hepatic cytochrome P450 3A4 activity

STUDY OBJECTIVES: To investigate the effect of high-dose vitamin C on cytochrome P450 (CYP) 3A4 activity, and to evaluate possible sex-specific effects on CYP3A4 activity. DESIGN: Single-center longitudinal study. SETTING: Tertiary- and specialty-care teaching hospital. SUBJECTS: Fourteen healthy Caucasian adult volunteers (seven men, seven women). INTERVENTION: Subjects self-administered vitamin C 500 mg twice/day for 14 days. MEASUREMENTS AND MAIN RESULTS: Hepatic CYP3A4 activity was measured by using the erythromycin breath test on days 1 (baseline) and 15. Overall, no significant effect of vitamin C on CYP3A4 activity was observed. Sex and baseline results were significant predictors of changes in CYP3A4 activity. In men, mean activity increased by 21.9% (95% confidence interval -3.88-47.6%). The effect in women was not consistent. CONCLUSION: Sex and baseline CYP3A4 activity appeared to influence the effect of vitamin C on CYP3A4 activity.     

Dietary intake,nutrition, and fetal alcohol spectrum disorders in the Western Cape Province of South Africa

In this study, we describe the nutritional status of women from a South African community with very high rates of fetal alcohol spectrum disorders (FASD). Nutrient intake (24-h recall) of mothers of children with FASD was compared to mothers of normal controls. Nutrient adequacy was assessed using Dietary Reference Intakes (DRIs). More than 50% of all mothers were below the Estimated Average Requirement (EAR) for vitamins A, D, E, and C, thiamin, riboflavin, vitamin B₆, folate, calcium, magnesium, iron, and zinc. Mean intakes were below the Adequate Intake (AI) for vitamin K, potassium, and choline. Mothers of children with FASD reported significantly lower intake of calcium, docosapentaenoic acid (DPA), riboflavin, and choline than controls. Lower intake of multiple key nutrients correlates significantly with heavy drinking. Poor diet quality and multiple nutritional inadequacies coupled with prenatal alcohol exposure may increase the risk for FASD in this population.     

Excretion of volatile nitrosamines in a rural population in relation to food and drinking water consumption.

Urinary excretion of volatile nitrosamines was assessed in 59 non-smokers living in a rural county of Québec, Canada. Water and food intakes were measured by means of a 24-hour recall. Nitrates were analyzed in the tap water of all participants (geometric mean=2.0 mg nitrate-N/L) and dietary intakes of nitrate and vitamins C and E were estimated via a validated Canadian food database. Urine was collected over the same 24-hour period and analyzed for nitrates by hydrazine reduction and for volatile nitrosamines by gas-chromatography/mass spectrometry. N-Nitrosopiperidine (NPIP) was found in urine samples from 52 of the 59 subjects. Geometric mean of NPIP urinary excretion was 67 ng/day and maximum value was 1045 ng/day. No other volatile nitrosamine was detected. There was a correlation between urinary nitrate excretion and total nitrate intake (r=0.71, P < 0.001). However, no relationship was found between urinary NPIP excretion and either nitrate excretion, dietary or water nitrate intakes. NPIP excretion was significantly correlated to coffee intake (r=0.40, P=0.002) and this relation was not modified by vitamin intake. We conclude that nitrate intake is not related to nitrosamine excretion in this rural population. The influence of coffee consumption on NPIP excretion deserves further attention.     

Posture and theophylline kinetics.

The effect of posture on theophylline kinetics was examined in six healthy men who took 450 mg slow-release aminophylline orally at the same time of day on two separate occasions. On one day they remained standing and on the other supine throughout. Plasma theophylline was measured hourly for 6 h from ingestion. Mean theophylline levels were significantly higher in the standing position at all times (P less than 0.01). We conclude that diurnal variation in theophylline kinetics can be explained, at least in part, by differences in posture.     

What do middle-aged New Zealanders eat? A dietary survey in 50-54 year olds in south Canterbury and north Otago

Information on diet was obtained from a random sample of 50-54 year olds in October 1985 when a health survey was conducted in the Timaru health district. This survey formed part of the international cardiovascular diseases and alimentary comparison (CARDIAC) study. A seven-day dietary history was obtained from 99 male and 82 female participants who were not taking any antidiabetic or antihypertensive medication. The median daily energy intake was 10.5 MJ for the men and 6.3 MJ for the women. The median daily total fat intake for men and women respectively was 103 g and 68 g. The median ratio of polyunsaturated to saturated fatty acids was low, 0.19 for the men and 0.18 for the women. Total fat contributed 37.5% to energy intake of men and 38.5% to energy intake of women and alcohol contributed 5.1% for men and 2.1% for women. Mineral and vitamin intakes were generally satisfactory. A substantial proportion of the participants, particularly women, claimed to have decreased their total food, fat, salt, meat, eggs and milk intakes and to have increased their vegetable and fish consumption.     

Estimated intake levels for Finnish children of methylmercury from fish

Methylmercury (MeHg) is a well-known neurotoxic agent, and consumption of contaminated fish is the principal environmental source of MeHg exposure in humans. Children are more susceptible to adverse effects than adults. No previous specific data exist for intake by Finnish children of methylmercury from fish. We estimated fish consumption and MeHg intakes from species most commonly consumed by Finnish children aged 1–6 years. The total mercury concentrations were determined in fish species consumed, and age-specific methylmercury intakes were derived. We also examined safety margins and the proportion of children exceeding the tolerable daily intakes set by international expert bodies. The daily intake of MeHg ranged from 0 to 0.33 μg/kg bw. The strictest reference value 0.1 μg/kg bw/day for MeHg, proposed by USEPA, was exceeded by 1–15% of the study population, and FAO/WHO JECFA provisional tolerable weekly intake of 1.6 μg/kg bw was exceeded by 1% of boys and 2.5% of girls aged 6 years. Intakes of 1-year old girls were higher than of boys, whereas for 3-year olds they were the opposite. The highest intakes were observed for 6-year-old boys and girls. There was great variation in the estimated MeHg intakes among Finnish children.     

Vitamin C ameliorates fluoride-induced embryotoxicity in pregnant rats

Oral administration of sodium fluoride (40 mg/kg body weight) from day 6 to 19 of gestation caused, as compared to control, significant reductions in body weight, feed consumption, absolute uterine weight and number of implantations. Significantly higher incidence of skeletal (wavy ribs, 14th rib, <6 sternal centre, dumbell-shaped second and fifth sternebrae, incomplete ossification of skull and thickening of tibia) and visceral (subcutaneous haemorrhage) abnormalities were also observed in NaF-treated dams than that of control. Oral administration of vitamin C (50 mg/kg body weight) and vitamin E (2 mg/0.2 ml olive oil/animal/day) from day 6 to 19 of gestation along with NaF significantly ameliorates NaF-induced reductions in body weight, feed consumption, absolute uterine weight (only with vitamin E treatment) and number of implantations. As compared with NaF-treated alone, the total percentage of skeletal and visceral abnormalities were significantly lowered in fluoride plus vitamin C-treated animals. Vitamin E was less effective. These findings suggest that vitamin C significantly reduced the severity and incidence of fluoride-induced embryotoxicity in rats.     

The usage, occurrence and dietary intakes of white mineral oils and waxes in Europe.

Dietary exposures to mineral hydrocarbons were estimated from information about patterns of usage, concentrations in foods and quantities of foods consumed. An industry survey showed that the largest usage of food-grade white mineral oils was in plastics manufacture although the majority are used in non-food applications. The largest volumes of wax usage were in packaging. Conservative estimates indicated that daily intakes of white mineral oils ranged from 0.39 to 0.91 mg/kg bw/day for adults and from 0.75 to 1.77 mg/kg bw/day for children (mean and 97.5th percentiles). Total wax intakes ranged from 0.08 to 0.19 mg/kg bw/day for adults and 0.23 to 0.64 mg/kg bw/day for pre-school children. When usage factors were applied, estimates of chronic intakes of white oils were reduced to 0.09-0.20 mg/kg bw/day for adults and to 0.17-0.39 mg/kg bw/day for children. Total wax intakes were reduced to 0.01-0.02 mg/kg bw/day for adults and to 0.02-0.06 mg/kg bw/day for children. For white mineral oils the principal source of exposure for most consumers was imported de-dusted grain. The principal source of potential wax exposure was from glazing agents on confectionery. There was no evidence of intakes exceeding SCF ADIs for microcrystalline waxes or certain white mineral oils and levels of exposure were similar to those of naturally-occurring mineral hydrocarbons in foods.     

Dietary exposure to essential and toxic trace elements from a Total diet study in an adult Lebanese urban population

This study assesses, by the Total diet study approach, the adequacy of micronutrient intake (Co, Cu, Fe, Mn, Ni, Zn) and the dietary exposure of a Lebanese adult urban population to two toxic elements (Cd, Pb). The foods that made up the average ‘total diet’ were derived from a previous individual consumption survey. A total of 1215 individual foods were collected, prepared and cooked prior to analysis. Analytical quantification was performed using inductively coupled plasma mass spectrometry. Average daily intakes of Co (11.4 μg/day), Cu (1104.19 μg/day), Fe (13.00 mg/day), Mn (2.04 mg/day), Ni (126.27 μg/day) and Zn (10.97 mg/day) were below toxicological reference values and were found to satisfy nutritional recommendations, except for manganese in men and iron in women. Average dietary exposure to Pb and Cd represented 3.2% and 21.7% of the respective provisional tolerable weekly intakes. Estimates of dietary intakes of iron appeared to be inadequate for 63% of adult women. These findings should constitute a current measure of assessing the adequacy and safety of foods consumed in Lebanon and may be a basis for future monitoring studies.