To determine if usual nutrient intake is related to a 5-year change in the amount of lens nuclear opacification assessed by computer-assisted image analysis.
A sample of 408 Boston, Mass-area women from the Nurses' Health Study aged 52 to 74 years at baseline participated in a 5-year study related to nutrition and vision. Usual nutrient intake was calculated as the average intake from 5 food frequency questionnaires that were collected over a 13- to 15-year period before the baseline evaluation of lens nuclear density. Duration of vitamin supplement use before baseline was determined from 7 questionnaires collected during this same period. We assessed the degree of nuclear density (opacification) using computer-assisted image analysis of digital lens images with amount of nuclear density measured as a function of average pixel gray scale, ranging from 0 (clear) to 255 (black).
Median (range) baseline and follow-up nuclear densities were 44 (19 to 102) and 63 (32 to 213). The median (range) 5-year change in nuclear density was 18 (-29 to 134) and was positively correlated with the amount of opacification at baseline (Spearman correlation coefficient = 0.35; P<.001). Geometric mean 5-year change in nuclear density was inversely associated with the intake of riboflavin (P trend = .03) and thiamin (P trend = .04) and duration of vitamin E supplement use (P trend = .006).
Our results suggest that long-term use of vitamin E supplements and higher riboflavin and/or thiamin intake may reduce the progression of age-related lens opacification.
"A cross-sectional study of 2,900 Australian men and women, 49 years of age and older, found that those in the highest quintile of thiamine intake were 40% less likely to have nuclear cataracts than those in the lowest quintile (Cumming et al. 2000). In addition, a recent study of 408 U.S. women found that higher dietary intakes of thiamine were inversely associated with 5-year change in lens opacification (Jacques et al. 2005). High dose thiamine therapy may also help reverse microalbuminuria in patients with type 2 diabetes (Rabbani et al. 2009). "
[Show abstract][Hide abstract] ABSTRACT: Thiamine pyrophosphate (vitamin B1) is an essential nutrient in the human diet, and is often referred as the energy vitamin. Potato contains modest amounts of thiamine. However, the genetic variation of thiamine concentrations in potato has never been investigated. In this study, we determined thiamine concentrations in freshly-harvested unpeeled tubers of 54 potato clones, the majority of them originating from the Pacific Northwest Potato Development Program. Tubers from 39 clones were collected from four different environmental conditions. Thiamine concentrations ranged from 292 to 1,317 ng g-1 fresh weight, which gives a good estimate of the genetic variation available in Solanum tuberosum ssp. tuberosum. Thirteen clones/varieties contained >685 ng g-1 fresh weight and four had >800 ng g-1 fresh weight over multiple harvests, indicating that these genotypes would contribute a significant amount of thiamine in the diet (>10% of the Recommended Daily Allowance based on a 175- or 150-g serving, respectively). Broad-sense heritability for thiamine content was calculated as 0.49 with a 95% confidence interval of 0.21-0.72, suggesting that genetic variation accounted for about 50% of the observed variation. There were significant clone and clone x environment effects. After accounting for environmental variation, 25 clones were unstable across environments. Tubers harvested at a mature stage late in the growing season had higher amounts of thiamine than tubers harvested at a young stage early in the season. Storage at cold temperature did not lead to significant thiamine loss; instead, thiamine concentrations slightly increased during storage in some genotypes. These results suggest that increasing the concentration of thiamine in potato is feasible and that all potato varieties may one day be a significant source of thiamine in the human diet.
American Journal of Potato Research 07/2011; 88(4):374-385. DOI:10.1007/s12230-011-9203-6 · 1.20 Impact Factor
"In another study, Vitamin E supplementation was also found to have no effect on cataract formation (McNeil et al., 2004). In contrast Jacques et al. (2005), Chylack et al. (2002) and Valero et al. (2002), reported that vitamin E supplementation reduced the progression of age-related lens opacification . Vitamin E was also included, along with vitamin C, in the ideal ocular nutritional supplement proposed by Bartlett and Eperjesi (2004a). "
[Show abstract][Hide abstract] ABSTRACT: Vitamin and mineral deficiencies are common in developing countries, but also occur in developed countries. We review micronutrient deficiencies for the major vitamins A, cobalamin (B(12)), biotin (vitamin H), vitamins C and E, as well as the minerals iron, and zinc, in the developed world, in terms of their relationship to systemic health and any resulting ocular disease and/or visual dysfunction. A knowledge of these effects is important as individuals with consequent poor ocular health and reduced visual function may present for ophthalmic care.
"P for trend ¼ 0.04) in men but not women with the highest vs. lowest a-carotene intake but found a 2.62 times increased rate of cataract (RR ¼ 2.62; CI ¼ 1.12e6.13) in women but not men with the highest vs. lowest serum a-carotene level in a retrospective study of 400 subjects. The remaining five studies showed no effect (Chasan-Taber et al., 1999b; Jacques et al., 2001, 2005; Lyle et al., 1999a, b) (Fig. 7a). 126.96.36.199. "
[Show abstract][Hide abstract] ABSTRACT: Loss of vision is the second greatest, next to death, fear among the elderly. Age-related cataract (ARC) and maculopathy (ARM) are two major causes of blindness worldwide. There are several important reasons to study relationships between risk for ARC/ARM and nutrition: (1) because it is likely that the same nutritional practices that are associated with prolonged eye function will also be associated with delayed age-related compromises to other organs, and perhaps, aging in general, (2) surgical resources are insufficient to provide economic and safe surgeries for cataract and do not provide a cure for ARM, and (3) there will be considerable financial savings and improvements in quality of life if health rather than old age is extended, particularly given the rapidly growing elderly segment of our population. It is clear that oxidative stress is associated with compromises to the lens and retina. Recent literature indicates that antioxidants may ameliorate the risk for ARC and ARM. Given the association between oxidative damage and age-related eye debilities, it is not surprising that over 70 studies have attempted to relate antioxidant intake to risk for ARC and ARM. This article will review epidemiological literature about ARC and ARM with emphasis on roles for vitamins C and E and carotenoids. Since glycation and glycoxidation are major molecular insults which involve an oxidative stress component, we also review new literature that relates dietary carbohydrate intake to risk for ARC and ARM. To evaluate dietary effects as a whole, several studies have tried to relate dietary patterns to risk for ARC. We will also give some attention to this emerging research. While data from the observational studies generally support a protective role for antioxidants in foods or supplements, results from intervention trials are less encouraging with respect to limiting risk for ARC/ARM prevalence or progress through antioxidant supplementations, or maintaining higher levels of antioxidants either in diet or blood. Without more information it is difficult to parse these results. It would be worthwhile to determine why the various types of studies are not yielding similar results. However, there are many common insults and mechanistic compromises that are associated with aging, and proper nutrition early in life may address some of these compromises and provide for extended youthful function later in life. Indeed, proper nutrition, possibly including use of antioxidant supplements for the nutritionally impoverished, along with healthy life styles may provide the least costly and most practical means to delay ARC and ARM. Further studies should be devoted to identifying the most effective strategy to prevent or delay the development and progress of ARC/ARM. The efforts should include identifying the right nutrient(s), defining useful levels of the nutrient(s), and determining the age when the supplementation should begin.
Experimental Eye Research 03/2007; 84(2):229-45. DOI:10.1016/j.exer.2006.05.015 · 2.71 Impact Factor
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