beta-carotene and Eye-Diseases

Topics: Administration, Ophthalmic; Antioxidants; beta Carotene; Carotenoids; Cryptoxanthins; Eye Diseases; Female; Fruit; Humans; Lutein; Lycopene; Male; Neoplasms; Osteoporosis; Vegetables; Xanthophylls; Zeaxanthins

Based on extensive epidemiological observation, fruits and vegetables that are a rich source of carotenoids are thought to provide health benefits by decreasing the risk of various diseases, particularly certain cancers and eye diseases. The carotenoids that have been most studied in this regard are beta-carotene, lycopene, lutein and zeaxanthin. In part, the beneficial effects of carotenoids are thought to be due to their role as antioxidants. beta-Carotene may have added benefits due its ability to be converted to vitamin A. Additionally, lutein and zeaxanthin may be protective in eye disease because they absorb damaging blue light that enters the eye. Food sources of these compounds include a variety of fruits and vegetables, although the primary sources of lycopene are tomato and tomato products. Additionally, egg yolk is a highly bioavailable source of lutein and zeaxanthin. These carotenoids are available in supplement form. However, intervention trials with large doses of beta-carotene found an adverse effect on the incidence of lung cancer in smokers and workers exposed to asbestos. Until the efficacy and safety of taking supplements containing these nutrients can be determined, current dietary recommendations of diets high in fruits and vegetables are advised.

Topics: Antioxidants; beta Carotene; Cardiovascular Diseases; Carotenoids; Diet; Eye Diseases; Free Radicals; Fruit; Humans; Lutein; Lycopene; Neoplasms; Vegetables; Xanthophylls; Zeaxanthins

Topics: Antioxidants; Ascorbic Acid; beta Carotene; Cardiovascular Diseases; Eye Diseases; Health Promotion; Humans; Neoplasms; Preventive Medicine; Vitamin E

Excessive consumption of energy and fat increases the risk for obesity. Snacks containing sucrose polyesters (SPE) as a dietary fat replacer are on the market in the United States. SPE products have been shown to lower concentrations of serum carotenoids in short-term studies. Experimental studies on the longer-term effects on health of decreased carotenoid concentrations are lacking. A 1-y randomized, double-blind, placebo-controlled parallel trial was performed. Subjects (n = 380) with a habitual low or high fruit and vegetable intake were assigned to the treatments (0, 7, 10 or 17 g/d SPE). SPE was given in the form of spreads, chips or both. The groups were compared for serum carotenoids, vitamins and markers of oxidative damage, eye health, cardiovascular health and immune status. After 1 y, serum lipid-adjusted carotenoids showed the largest decrease in the SPE chips and spread group (17 g/d) compared with the control group [alpha-carotene 33%; beta-carotene 31%, lycopene 24%, beta-cryptoxanthin 18%, lutein 18% (all P < 0.001) and zeaxanthin 13% (P < 0.05)]. Consumption of SPE spread (10 g/d SPE) decreased carotenoid concentrations by 11-29% (all P < 0.05). SPE chips (7 g/d SPE) decreased zeaxanthin (11%), beta-carotene (12%) and alpha-carotene (21%; all P < 0.05). Serum lipid adjusted alpha-tocopherol decreased significantly by 6-8% (all P < 0.001) in all SPE groups. No negative effects were observed on markers of oxidation, eye health, cardiovascular health or immune status. This study shows that decreases in serum carotenoid concentrations do not affect possible markers of disease risk.

Topics: Adolescent; Adult; Aged; alpha-Tocopherol; beta Carotene; Body Weight; Cardiovascular Diseases; Carotenoids; Dietary Fats, Unsaturated; Double-Blind Method; Endothelium, Vascular; Eye Diseases; Fatty Acids; Female; Health Status; Humans; Immunity; Lipid Peroxidation; Lipids; Macula Lutea; Male; Middle Aged; Patient Compliance; Placebos; Risk Factors; Sucrose; Xanthophylls; Zeaxanthins

In association with a study of actinic skin disease, we undertook a comprehensive survey of ocular disease in a population sample of the town of Nambour, Queensland, Australia. Particular emphasis was placed on those diseases with a putative relationship to exposure to solar radiation. In addition to collecting prevalence data, a randomized controlled trial was commenced to determine, among other things, if daily ingestion of 30 mg of beta-carotene supplements reduces the incidence or progression of ocular diseases possibly related to solar radiation exposure. The study design, population and methodology of the study are described in detail as a background to the future reporting of the results. The study should provide unique epidemiological information about eye disease in an Australian community setting due to the representative nature of the subjects and the comprehensive examination performed.

Topics: Adult; Aged; beta Carotene; Data Collection; Eye Diseases; Female; Food, Fortified; Humans; Male; Middle Aged; Ocular Physiological Phenomena; Photosensitivity Disorders; Prevalence; Pupil; Queensland; Sunlight; Visual Acuity; Visual Field Tests

Topics: beta Carotene; Eye Diseases; Fatty Acids, Omega-3; Humans; Lutein; Macular Degeneration; Zeaxanthins; Zinc

beta-carotene was first identified from the vitreous asteroid bodies (ABs) excised from one patient with asteroid hyalosis (AH) by confocal Raman microspectroscopy and was also verified by high performance liquid chromatography (HPLC). Two patients had been diagnosed with AH and intervened by surgical vitrectomy due to blurred vision. The morphology and components of both AB specimens were observed by optical microscopy and determined by using confocal Raman microspectroscopy and HPLC analysis, respectively. Surprisingly, two unique peaks at 1528 and 1157 cm(-1) were found in the Raman spectrum for the AB specimen of patient 1 alone, which were in close agreement with that of the Raman peaks at 1525 and 1158 cm(-1) for beta-carotene and/or lutein. However, HPLC analytical data clearly indicated that the retention time for the extracted sample from the AB specimen of patient 1 was observed at 13.685 min and just identical to that of beta-carotene (13.759 min) rather than lutein (2.978 min). In addition, the lack of any peak in the HPLC profile for the AB specimen of patient 2 also confirmed the absence of Raman peaks at 1525 and 1158 cm(-1). Thus this preliminary study strongly suggests that beta-carotene as a unique component of ABs was specifically detected from the AB specimen of one AH patient by using confocal Raman microspectroscopy and HPLC analysis.

Topics: Aged; Aged, 80 and over; beta Carotene; Chromatography, High Pressure Liquid; Eye Diseases; Female; Humans; Male; Spectrum Analysis, Raman; Vitrectomy; Vitreous Body

The results of epidemiologic studies have consistently shown associations between dietary intake or plasma carotenoid status and incidence of cancers and cardiovascular and eye diseases.. The aim was to assess whether vegetable-borne carotenoids (lycopene, lutein, and beta-carotene) compete for intestinal absorption and whether this affects the plasma status of carotenoids in the medium term (ie, after 3 wk).. During 3-wk periods separated by 3-wk washout periods, 20 women were supplemented with either 96 g tomato purée/d (14.98 mg lycopene + 1.50 mg beta-carotene), 92 g cooked chopped spinach/d (11.93 mg lutein + 7.96 mg beta-carotene), 96 g tomato purée/d + 92 g chopped spinach/d, 96 g tomato purée/d + 2 lutein pills (12 mg lutein), or 92 g chopped spinach/d + 1 lycopene pill (15 mg lycopene). Plasma carotenoids were measured before and after each supplementation period. The subjects also participated in postprandial experiments in which they ingested meals containing double amounts of the supplements described above. Carotenoids were measured in chylomicrons to assess the interaction of carotenoids on absorption.. Adding a second carotenoid to a meal that provided a first carotenoid diminished the chylomicron response to the first carotenoid. However, cosupplementation with a second carotenoid of a diet supplemented with a first carotenoid did not diminish the medium-term plasma response to the first carotenoid.. Consumption of carotenoids from different vegetable sources does not diminish plasma carotenoid concentrations in the medium term, despite the finding in postprandial testing of competitive inhibitory interactions among different carotenoids.

Topics: Adult; beta Carotene; Biological Availability; Cardiovascular Diseases; Carotenoids; Chylomicrons; Eye Diseases; Female; Humans; Intestinal Absorption; Lutein; Lycopene; Neoplasms; Nutritional Status; Postprandial Period; Seroepidemiologic Studies; Vegetables

Administration of large oral doses of retinyl palmitate has become the most widely practised vitamin A deficiency prevention strategy in developing countries. We conducted a follow-up study among 220 Senegalese children aged 2-7 years suffering from moderate undernutrition to determine the efficacy of vitamin A treatment on their vitamin A status assessed by biochemical and cytological (impression cytology with transfer) methods. The first examination (T = 0 m[onth]) was carried out during April 1989, before the mango (Mangifera indica L,) harvest. The second examination (T = 2 m) was carried out 2 months after vitamin A treatment during June 1989 when ripe mangoes become widely available. Conjunctival cells of the eyes of the children with or without ocular inflammation were responsive to vitamin A administration (P < 0.01). There was a significant increase (P < 0.001) in mean serum retinol and beta-carotene levels between T = 0 m and T = 2 m. Mean serum retinol-binding protein (RBP) and transthyretin (TTR) levels did not differ significantly (P > 0.05) at T = 0 m and T = 2 m. Despite the intake of vitamin A, 54% of the children who had abnormal cytology at T = 0 m remained abnormal at T = 2 m. This was due to inadequate levels of TTR and RBP, presumably due to the cereal diet eaten by the Senegalese population. children with abnormal eye cytology had lower serum retinol levels than those with normal eyes at T = 0 m, and beta-carotene values did not correlate with eye cytological abnormalities at T = 0 m. Children with normal cytology had higher serum retinol and also beta-carotene levels than those with abnormal cytology after massive oral doses of vitamin A and consumption of mangoes at T = 2 m. Retinyl palmitate may, therefore, only lead to partial cytological improvement due to a lack of retinol-carrier proteins but dietary beta-carotene may also be involved.

Topics: beta Carotene; Carotenoids; Child; Child, Preschool; Conjunctiva; Diterpenes; Drug Administration Schedule; Eye Diseases; Follow-Up Studies; Fruit; Humans; Retinyl Esters; Senegal; Vitamin A; Vitamin A Deficiency

Topics: Adult; beta Carotene; Canthaxanthin; Carotenoids; Cell Transformation, Neoplastic; Child; Child, Preschool; Electrosurgery; Eye Diseases; Female; Humans; Infant; Male; Neurologic Manifestations; Skin Diseases; Tretinoin; Xeroderma Pigmentosum