Adequate Intake Of Vitamin Research Articles

Nutrition and immunity in cancer

The purpose of this article is to give a general overview of the effects of nutrition on the development of cancer as well as part of a therapeutic approach. There is much evidence that diet and lifestyle can alter the risk of cancer development as is the case for many other chronic diseases. This may be through a direct action on the immune system, either by enhancing or suppressing it, as well as on the development of the tumour itself, by modulating gene expression or by antioxidant activity. Protective effects can be achieved by adequate intakes of vitamins A and C, beta-carotene, selenium and n-3 fatty acids among others, while negative effects are found mainly with high intakes of n-6 and saturated fatty acids. Weight gain, obesity and lack of regular physical activity have also been associated with an increased risk of cancer. The protective effects are best observed when adequate diet and lifestyle are present together. With respect to the therapeutic role of nutrition in cancer, it has been observed that the use of pre- or post-operative enteral or parenteral nutrition may improve patients' survival rates and quality of life; however, more research is needed in this particular area. Breast, colon, rectum, prostate, stomach and lung are the types of cancer most commonly associated with diet or dietary components.

Do elderly fallers report adequate intake of vitamin D and calcium?

Do elderly fallers report adequate intake of vitamin D and calcium?

Combination of fortified foods and dietary supplementation needed for long term care residents to consume adequate intakes of vitamin D and calcium

Combination of fortified foods and dietary supplementation needed for long term care residents to consume adequate intakes of vitamin D and calcium

Determination of Fat-Soluble Vitamins in Human Plasma, Breast Milk and Food Samples: Application in Nutrition Survey for Establishment of "Dietary Reference Intakes for Japanese"

Dietary habits are an important risk factor for lifestyle-related diseases. To carry out a nutrition survey of fat-soluble vitamins, we developed determination methods of fat-soluble vitamins using liquid chromatography-atmospheric pressure chemical ionization/tandem mass spectrometry or high-performance liquid chromatography with fluorescence detection. In these methods, stable isotope-labeled compounds or vitamin K analogs with a saturated side-chain were used as internal standards. These methods have high sensitivity and sufficient accuracy, and we applied them in a nutrition survey about the status of fat-soluble vitamins in Japanese women. Plasma concentrations of 25-hydroxyvitamin D3 [25(OH)D3] and 25-hydroxyvitamin D2 [25(OH)D2] in healthy postmenopausal women (n=98) were 20.5±7.9 and 0.4±1.4 ng/ml, respectively. A significant negative correlation in plasma levels between 25-hydroxyvitamin D [25(OH)D] and parathyroid hormone was observed. For vitamin K homologs, plasma levels of phylloquinone (PK), menaquinone-4 (MK-4) and menaquinone-7 (MK-7) in Japanese women of various ages (n=1409) were 1.03±0.90, 0.12±0.28 and 6.71±13.6 ng/ml, respectively. The mean total vitamin K intake of Japanese young women was about 230 μg/day, and 94% of participants met the Adequate Intake of vitamin K for women aged 18-29 years in Japan, 60 μg/day. Moreover, we determined fat-soluble vitamins in breast milk collected from Japanese lactating women and revealed that the contents of all-trans-retinol, vitamin D3, 25(OH)D3, α-tocopherol, PK and MK-4 in breast milk were 0.39±0.14 μg/ml, 0.10±0.15 ng/ml, 0.08±0.04 ng/ml, 3.96±1.84 μg/ml, 3.56±2.19 and 1.77±0.68 ng/ml, respectively.

Prevalence of Vitamin D Inadequacy Among Postmenopausal North American Women Receiving Osteoporosis Therapy

An adequate intake of vitamin D and calcium is viewed as a necessary part of treating osteoporosis. Recommended daily intake in the United States is 400 IU (10 μg) in persons aged 51–70 years and 600 IU (15 μg) for those over age 70. Vitamin D status is evaluated by measuring the serum level of 25-hydroxyvitamin D (25[OH]D), the major circulating metabolite of vitamin D. Many epidemiologic studies have confirmed that vitamin D inadequacy is a common problem throughout the world. This study estimated serum 25(OH)D levels in 1536 postmenopausal Norh American women who were receiving medication to prevent or treat osteoporosis. All of them had been postmenopausal for at least 2 years and were 55 years of age or older. More than 90% of the study population was white and the mean age was 71 years. Nearly 60% of participants reported taking 400 IU or more of vitamin D daily. Nearly one fifth (18.7%) had had a fracture caused by falling within the past 5 years. The mean serum 25(OH)D level was 30.4 ng/mL, and the 25th and 75th percentile values were 22 and 37 ng/mL, respectively. Several cutoff points were used in this study. Regardless of the level used, vitamin D inadequacy was significantly greater in women who reported taking less than 400 IU of vitamin D daily. At a cutoff point of 30 ng/mL, the prevalence of inadequacy was 63% in women taking less than 400 IU daily and 45% in those taking 400 IU or more. Multivariate analysis yielded 8 variables that were significantly associated with vitamin D inadequacy: age over 80, being nonwhite, a body mass index exceeding 30 kg/m2, taking medications that affect vitamin D metabolism, supplementation of less than 400 IU daily, a lack of exercise, failure to discuss the importance of vitamin D with a physician, and an educational level below grade 12. The number of risk factors correlated with the risk of vitamin D inadequacy but, even in 203 women who lacked any risk factors, the prevalence of vitamin D inadequacy was 32%. Women with relatively low serum 25(OH)D levels had a significantly higher prevalence of secondary hyperparathyroidism. The prevalence of vitamin D inadequacy in postmenopausal women in North America who are receiving medication to forestall or treat osteoporosis is unacceptably high. Both physicians and the public need to be better educated about how to optimize vitamin D supplementation in these women.

Vitamin D Insufficiency in Preadolescent African-American Children

To determine the proportion of vitamin D insufficiency in 6- to 10-year-old preadolescent African-American children residing in Pittsburgh, Pennsylvania and to estimate their therapeutic response to vitamin D 400 IU/day for 1-month, an open-label pre- and post-comparison of vitamin D status following vitamin D 400 IU daily for 1 month during winter and early spring was conducted. Outcomes included serum calcium, phosphorus, albumin, 25 hydroxyvitamin D [25 (OH) D], 1, 25 dihydroxyvitamin D [1, 25 (OH) (2) D], parathyroid hormone (PTH), and markers of bone turnover (serum bone-specific alkaline phosphatase, osteocalcin, and urine n-telopeptide crosslinked collagen type 1 [NTX]). Dietary intake of vitamin D was assessed using a food frequency questionnaire. Forty-one of the 42 enrolled subjects (mean age: 8.9 +/- 1.2 yrs [SD]) were analyzed, and 20/41 (49%) were vitamin D insufficient. Vitamin D insufficient group had a suggestive trend of being older (9.2 +/- 1.0 years vs. 8.5 +/- 1.3 years, p = 0.06) and more pubertally advanced (Tanner II: 7/20 vs. Tanner II: 1/21, p = 0.02). Mean dietary intake of vitamin D was 277 ( 146 IU/day (n = 41). Adequate intake for vitamin D (200 IU/day) was not met in 16/41 (39%); however, the dietary intake of vitamin D was not significantly different between the vitamin D insufficient and vitamin D sufficient groups.

Osteoporosis and sunlight

Vitamin D deficiency causes osteomalacia, osteoporosis and may contribute to bone fractures. Vitamin D is synthesized in the skin by the sunlight exposure and is also obtained from dietary sources. In the U.S., it was recommended that the adequate intake of vitamin D for adults aged from 51-70 years and 70 and more required 400 and 600 IU/day, respectively. Since dietary intake of vitamin D for middle-aged and elderly Japanese is estimated to be 300-400 IU/day, approximately 100-200 IU/day should be provided through the skin. Considering the risks of skin cancer caused by sunlight exposure, short trips outside amid life's daily routine on sunny days, and 30-60 minutes on rainy days and during times when sun exposure is inadequate to produce enough vitamin D in the skin would be appropriate.

Calcium and vitamin D intakes during infancy, childhood and adolescence

Adequate intakes of calcium and vitamin D are necessary to prevent vitamin D deficiency or increase of plasma parathyroid hormone (PTH) level caused by vitamin D insufficiency. According to the National Nutrition Survey in Japan, 2001 by Ministry of Health, Labour and Welfare, Japan, the average of calcium and vitamin D intakes have not met their RDA at 1-2 ages, and a low calcium intake was observed during adolescence. It is important to know the adequate intake of vitamin D to compensate the low calcium intake in Japanese children.

Dental caries and beverage consumption in young children.

Dental caries and beverage consumption in young children.

Plasma vitamin A and C status of in-school adolescents and associated factors in Enugu State, Nigeria.

The study was undertaken to determine the intake of vitamin A and C and plasma concentrations of these vitamins among in-school adolescents. The factors affecting the vitamin status of these adolescents were also determined. Data for this report were obtained from a cross-sectional survey of 600 in-school adolescents in Nsukka local government area (LGA) of Enugu State, Nigeria. Ninety and 45 of the adolescents were randomly selected for determining plasma concentrations of vitamin A and C and intake of these vitamins respectively. Dietary assessment was done using a three-day weighed food intake method. Venous blood samples were collected and used for determining plasma vitamin A using the trifluoroacetic acid (TFA) method, while plasma vitamin C was determined by the thiourea method. Values obtained were matched against standards. The intake of vitamin A by all the adolescents was adequate (126-137% of recommended intake), while the intake of vitamin C was inadequate (51-91% of recommended intake). The mean intake of vitamin C was higher among males (23.7 +/- 0.71-27.3 +/- 8.0) than among females (15.3 +/- 2.8-19.5 +/- 5.1). Despite the adequate intake of vitamin A, 40% of the male and 32% of the female adolescents had low plasma concentrations of the vitamin (< 20 microg/dL). On the other hand, concentrations of plasma vitamin C were low among about 47% of these adolescents. Using multiple regression analysis, the two most important variables influencing vitamin A status were household size (b = -0.629; p < 0.0 1) and nutrition knowledge (b = -1.372; p < 0.01), while for vitamin C status, these were household size (b = -0.110; p = 0.05) and age (b = 0.226; p < 0.05). The daytime students had a significantly (p < 0.05) better vitamin A and C status than the boarders. The prevalence of vitamin A and C deficiencies among the adolescents may be more than estimated due to inadequate intake and/or poor bioavailability. This may pose a serious health risk for adolescents. There is, therefore, a need for adequate nutrition education and awareness about healthy lifestyles among Nigerian adolescents.

Ingesta de antioxidantes y grasas en pacientes con asma polínica

The aim of our work was to evaluate the dietary intake of patients with asthma. A total of 54 subjects with asthma were enrolled (average age 23.59 +/- 9.6 years). In all patients, we determined weight, height and the body mass index and a three days nutritional questionnaire was administered. The total calories intake was normal. Distribution of calories was: 39.7% carbohydrates, 19.4% proteins and 40.9% lipids. Low intakes of vitamin A, D, E, thiamine and folic acid were detected, and an adequate intake of vitamin K, C, niacin and B12 was observed. The mineral intake showed an increase in calcium and a decrease in magnesium, zinc, iodine and selenium. The intake of polyunsaturated omega-9 fatty acids was 34.8(12.7) g/day, that of polyunsaturated omega-6 fatty acids was 5.7(3.1) g/day, and the intake of polyunsaturated omega-3 fatty acids was 0.85(0.31) g/day. Saturated fats represented a 18.4%. The omega6/omega3 ratio was 6.63. Asthmatic patients have a low intake of vitamins A and E but an increase in the intake of saturated fatty acids.

Adequate Intakes of Vitamin E and Protein Prevent Increases of Oxidative Damage to DNA, Lipids, and Protein Induced by Total Body Irradiation in Mice

: We examined the influence of the level of dietary protein or vitamin E (VE) on oxidative damage to DNA, lipids, and protein in the liver after total body irradiation (TBI) with X-rays at 1 or 4 Gy. Levels of 8-hydroxydeoxyguanosine, thiobarbituric acid-reactive substances, and protein carbonyls in the liver did not differ among the groups that did not receive TBI. However, oxidative damage to lipids and protein was increased by TBI only in the 1% protein group. DNA damage, lipid peroxidation, or protein oxidation in the liver was increased by TBI in a dose-dependent manner, and the damage was consistently higher in the 1% than in the 20% protein group. In the 1% protein group, a greater decrease in relative spleen weight by TBI was also observed. Concentrations of antioxidants (vitamins C and E and glutathione) in the liver were lower and the concentration of nonheme iron in the liver was higher in the 1% than in the 20% protein group. Mice fed a 1% protein diet became susceptible to TBI-induced oxidative damage, and decreases in antioxidant levels and an increase in iron level were involved in the mechanism of this susceptibility. These results suggest that dietary VE and protein can prevent oxidative damage to DNA, lipid, and protein in mice subjected to TBI. Consumption of a VE-free diet significantly increased 8-hydroxydeoxyguanosine levels in DNA from mice fed the 1% protein diet with TBI, but such changes were not detected in DNA from mice fed the 20% protein diet.

Vitamin D intake and vitamin D status of Australians.

The main source of vitamin D for Australians is exposure to sunlight. Thus, levels of serum 25-hydroxyvitamin D(3), the indicator of vitamin D status, vary according to the season and are lower at the end of winter. In Australia and New Zealand, the prevalence of vitamin D deficiency varies, but is acknowledged to be much higher than previously thought. One study found marginal deficiency in 23% of women, and another frank deficiency in 80% of dark-skinned and veiled women. The groups at greatest risk of vitamin D deficiency in Australia are dark-skinned and veiled women (particularly in pregnancy), their infants, and older persons living in residential care. Only a few foods (eg, fish with a high fat content) contain significant amounts of vitamin D. In Australia, margarine and some milk and milk products are currently fortified with vitamin D. The average estimated dietary intake of vitamin D for men is 2.6-3.0 g/day and for women is 2.0-2.2 g/day. The estimated dietary requirement of vitamin D is at least 5.0 g/day and may be higher for older people. Adequate intake of vitamin D is unlikely to be achieved through dietary means, particularly in the groups at greatest risk, although vitamin D-fortified foods may assist in maintaining vitamin D status in the general population. An appropriate health message for vitamin D needs to balance the need for sunshine against the risk of skin cancer.

Hypovitaminosis D prevalence and determinants among African American and white women of reproductive age: third National Health and Nutrition Examination Survey, 1988–1994 ,

Recent reports of rickets among African American children drew attention to the vitamin D status of these infants and their mothers. African American women are at higher risk of vitamin D deficiency than are white women, but few studies have examined determinants of hypovitaminosis D in this population. We examined the prevalence and determinants of hypovitaminosis D among African American and white women of reproductive age. We examined 1546 African American women and 1426 white women aged 15-49 y who were not pregnant and who participated in the third National Health and Nutrition Examination Survey (1988-1994). Hypovitaminosis D was defined as a serum 25-hydroxyvitamin D concentration < or =37.5 nmol/L. Multiple logistic regression was used to examine the independent association of dietary, demographic, and behavioral determinants of hypovitaminosis D. The prevalence of hypovitaminosis D was 42.4 +/- 3.1% ( +/- SE) among African Americans and 4.2 +/- 0.7% among whites. Among African Americans, hypovitaminosis D was independently associated with consumption of milk or breakfast cereal <3 times/wk, no use of vitamin D supplements, season, urban residence, low body mass index, and no use of oral contraceptives. Even among 243 African Americans who consumed the adequate intake of vitamin D from supplements (200 IU/d), 28.2 +/- 2.7% had hypovitaminosis D. The high prevalence of hypovitaminosis D among African American women warrants further examination of vitamin D recommendations for these women. The determinants of hypovitaminosis D among women should be considered when these women are advised on dietary intake and supplement use.

Nutritional regulation of homocysteine: effects of drugs

Homocysteine plays a critical regulation role at the intersection of two metabolic pathways: remethylation and transsulfuration. Both are nutritionally regulated per se, and this issue constitutes the main goal of the present short review. In addition, several factors (i.e., drugs) may change the nutritional modulation, altering the normal functioning of the methionine/methylation cycle. The metabolism of a substrate is closely linked to that of it cofactors: in the case of homocysteine, there are three vitamins acting as cofactors or coenzymes: B6, B12 and folate. Vitamin B6 is involved in the formation of cystathionine from homocysteine (transsulfuration pathway). It is also critical for the formation of 5,10-methylentetrahydrofolate from tetrahydrofolate (folic acid derivatives), and therefore is closely related to the metabolism of folate. The latter is in conjunction with vitamin B12 involved in the remethylation of homocysteine to methionine. This reaction is B12-dependent. Different animal and human studies have proved the existence of a relation between vitamin status and homocysteine. Other dietary components as methionine content, riboflavin, alcohol or coffee consumption are being investigated in relation to homocysteine concentration. Drugs may interfere with the utilization of nutrients. This fact may be of special importance for vitamins (i.e., folate). Administration of drugs in populations with adequate vitamin intake is not usually a problem, but the existence of risk groups (the elderly, adolescents, smokers, dieters, etc.) may lead to specific vitamin deficiencies which may lead to elevated homocysteine. The case of folate is analysed since this vitamin shows the most reported number of interactions with drugs.

Cigarette smoke-induced protein oxidation and proteolysis is exclusively caused by its tar phase: prevention by vitamin C

We have reported before that whole phase cigarette smoke (CS) contains stable oxidants that cause oxidative damage and increased proteolysis of proteins [Free Radic. Biol. Med. 27 (1999) 1064]. Here, we demonstrate that these oxidants are exclusively present in the tar phase of the CS and not its gas phase and can almost wholly account for the observed whole phase CS-induced oxidation of human plasma proteins as well as extensive oxidative proteolysis of guinea pig lung and heart microsomal proteins in vitro. The mechanism of the tar phase CS-induced proteolysis of microsomal proteins involves two-steps: (i) initial oxidation of the proteins by oxidants present in the tar extract followed by (ii) rapid proteolytic degradation of the oxidized proteins by proteases present in the microsomes. Like the whole phase CS, the oxidative damage of proteins caused by the tar phase CS, as evidenced by the formation of protein carbonyl and bityrosine as well as loss of tryptophan residues and thiol groups, is also almost completely prevented by ascorbic acid and only partially by glutathione. Other antioxidants, including superoxide dismutase, catalase, vitamin E, β-carotene and mannitol are ineffective. This again leads us to suggest that adequate intake of vitamin C may help smokers to evade the CS-induced degenerative diseases associated with oxidative damage. The revelation of the acute toxicity of the tar phase with respect to CS-induced oxidative damage also urges the necessity of trapping it more effectively by suitable cigarette filters to reduce the health damage caused to smokers.

Severe Malnutrition Among Young Children—Georgia, January 1997–June 1999

In October 1999, the Georgia Department of Human Resources (GDHR) was notified of two cases of severe malnutrition in toddlers. Both cases were associated with the use of commercial alternative milk. In response, GDHR and CDC reviewed Georgia hospital records to assess the frequency and cause of hospitalized cases of rickets and protein energy malnutrition (PEM). The findings of this review indicated that, although no new cases were associated with milk alternatives, three children had PEM and six had vitamin D deficiency rickets. The children with rickets had been breast fed for approximately 6 months while receiving no vitamin D supplementation. Rickets is preventable through the adequate intake of vitamin D. The American Academy of Pediatrics (AAP) is examining vitamin D supplementation among breast-fed infants.

Vitamin D

Current Clinical Issues15 August 2000Vitamin DDeborah GesenswayDeborah GesenswaySearch for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-133-4-200008150-00103 SectionsAboutFull Text ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail At the peak of sunscreen season in the United States, an old debate continues. Should people ensure adequate intake of vitamin D by exposing themselves, even minimally, to sunlight? Many experts say yes, citing evidence that anywhere from 9% to 40% of Americans—depending on age, ethnicity, and locale—are deficient in vitamin D. Michael F. Holick, MD, professor of medicine and dermatology at Boston University Medical Center and one of the nation's top vitamin D researchers, recommends that people expose their face and arms to the sun for 5 to 10 minutes two to three times per week before applying sunscreen. ... Author, Article, and Disclosure InformationAffiliations: PreviousarticleNextarticle Advertisement FiguresReferencesRelatedDetails Metrics Cited byHerbs or Natural Products That Protect Against Cancer Growth: Part Three of a Four-Part SeriesRaquitismo carencial en la infancia: análisis de 62 casos 15 August 2000Volume 133, Issue 4Page: 318KeywordsBoneCalciumCancer preventionDietElderlyNutritionPrevention, policy, and public healthRecommended dietary allowanceVitamin DVitamin D deficiency ePublished: 15 August 2000 Issue Published: 15 August 2000 Copyright & PermissionsCopyright © 2000 by American College of Physicians. All Rights Reserved.Loading ...

Drugs–nutrient interactions: a potential problem during adolescence

The concept of drug-nutrient interactions is not new, but it has only recently gained currency in medicine. Although the elderly are normally considered to be at particular risk, other groups may also be at risk: infants, adolescents, pregnant women, alcohol and tobacco users, etc. In infants and adolescents there are several factors that may influence the possible interactions: firstly, nutrient needs are usually higher, mainly micronutrients; systems for detoxification of anutrients are not complete; the tendency to restricted diets (especially girls) that are unable to cover the actual recommended intakes for a number of micronutrients (i.e. vitamins); and the dangerous increase in alcohol consumption either in males or females. Administration of drugs in population with adequate vitamin intake is usually not a problem, but administration of drugs in those with borderline intake of vitamins or in patients with low nutritional status can result in symptomatic vitamin deficiency states. The groups at risk of poor vitamin status are smokers (a high proportion of adolescents are active smokers); dieters (skipping meals and dieting to lose weight frequently compromise micronutrient intake, and it should be considered that it is extremely difficult to meet all the requirements at intakes of less than 1,200 calories per day), oral contraceptive users, and pregnant and lactating women, excessive alcohol users, etc. The chapter also focuses on the case of folate: rapidly dividing tissues during the adolescent growth spurt increase requirements for folate. Because of this increased need, folate status appears to be of concern during the age of this rapid growth. A variety of drugs are known to interfere with vitamin utilization by blocking or altering transformation of the vitamin to its metabolically active form. Serum folate levels are known to be low in a high percentage of patients with rheumatoid arthritis, suggesting that aspirin alters the transport of folate by competition for binding sites on serum proteins. Methotrexate, a drug commonly used at low doses for the treatment of psoriasis, rheumatoid arthritis and certain liver disorders, limits the availability of methyl groups derived from one-carbon metabolism by inhibiting competitively a key enzyme in the intracellular folate metabolism. In humans, the antiepileptic drug valproic acid (VPA) is associated with two major adverse effects: teratogenicity and folate deficiency. The mechanisms by which VPA exerts the teratogenic or antifolate effect remain unclear, but an alteration in the methionine cycle is the strongest hypothesis proposed.

Impact of dietary fat and fiber intake on nutrient intake of adolescents.

To evaluate the impact of fat and fiber intake on energy and nutrient intake of 15-year-old adolescents. Twenty-four-hour dietary recalls were collected on a random sample of 15-year-olds. Subjects were then categorized into groups based on fat and fiber intake, with 319 students meeting criteria for 1 of 4 dietary intake quadrants: low fat, low fiber; low fat, high fiber; high fat, low fiber; and high fat, high fiber. Students with medium fat or fiber intakes were excluded from the study. Low-fat and high-fat intake were defined as <30% and >40% of total energy intake, respectively. Low- and high-fiber intake were defined as <15 g/day and >20 g/day, respectively. Low-fat and high-fiber intake had a minimal impact on energy intake and did not adversely affect nutrient intake. High-fiber intake was associated with greater likelihood of adequate intake of vitamins A, B6, B12, and C; niacin; thiamin; riboflavin; folacin; magnesium; iron; zinc; phosphorus; and calcium. High-fat intake was associated with greater likelihood of adequate vitamin B12 intake. Significant differences in fat and fiber intake distributions were found for ethnic background and gender, with more non-white than white students in the high-fat groups and more males than females in the high-fiber groups. A low-fat and high-fiber diet meeting current nutrition recommendations does not adversely affect energy or nutrient intake, increases nutrient density of the diet, and increases the likelihood of adequate intake for several key nutrients.