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In addition, results from a pooled analysis of randomized controlled trials of zinc supplementation in developing countries suggest that zinc helps reduce the duration and severity of diarrhea in zinc-deficient or otherwise malnourished children [ 62 ]. Foods in nutrient-dense forms contain essential vitamins and minerals and also dietary fiber and other naturally occurring substances that may have positive health effects. The first phase of the initiative will run for 4 years. Time constraints, access to fresh, whole foods and grocery stores, culinary and nutritional knowledge, underestimating the additional demands of sport, recovery, and growth, are all factors that may lead many athletes to fall short of the recommended levels of nutrients. Abbott's segment revenues
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Several studies are described below in which zinc is administered as a lozenge or zinc-containing syrup that temporarily "sticks" in the mouth and throat. This allows zinc to make contact with the rhinovirus in those areas. In a randomized, double-blind, placebo-controlled clinical trial, 50 subjects within 24 hours of developing the common cold took a zinc acetate lozenge Compared with placebo, the zinc lozenges significantly reduced the duration of cold symptoms cough, nasal discharge, and muscle aches [ 67 ].
In another clinical trial involving participants with experimentally induced colds, zinc gluconate lozenges providing However, treatment with zinc acetate lozenges providing 5 or Neither zinc gluconate nor zinc acetate lozenges affected the duration or severity of cold symptoms in subjects with natural not experimentally induced colds in another trial [ 68 ].
In 77 participants with natural colds, a combination of zinc gluconate nasal spray and zinc orotate lozenges 37 mg zinc every 2—3 wakeful hours was also found to have no effect on the number of asymptomatic patients after 7 days of treatment [ 69 ].
In September of , Caruso and colleagues published a structured review of the effects of zinc lozenges, nasal sprays, and nasal gels on the common cold [ 66 ]. Of the 14 randomized, placebo-controlled studies included, 7 5 using zinc lozenges, 2 using a nasal gel showed that the zinc treatment had a beneficial effect and 7 5 using zinc lozenges, 1 using a nasal spray, and 1 using lozenges and a nasal spray showed no effect.
More recently, a Cochrane review concluded that "zinc lozenges or syrup is beneficial in reducing the duration and severity of the common cold in healthy people, when taken within 24 hours of onset of symptoms" [ 70 ].
The author of another review completed in also concluded that zinc can reduce the duration and severity of cold symptoms [ 65 ]. However, more research is needed to determine the optimal dosage, zinc formulation and duration of treatment before a general recommendation for zinc in the treatment of the common cold can be made [ 70 ]. As previously noted, the safety of intranasal zinc has been called into question because of numerous reports of anosmia loss of smell , in some cases long-lasting or permanent, from the use of zinc-containing nasal gels or sprays [ ].
Researchers have suggested that both zinc and antioxidants delay the progression of age-related macular degeneration AMD and vision loss, possibly by preventing cellular damage in the retina [ 71 , 72 ]. In a population-based cohort study in the Netherlands, high dietary intake of zinc as well as beta carotene, vitamin C, and vitamin E was associated with reduced risk of AMD in elderly subjects [ 73 ].
However, the authors of a systematic review and meta-analysis published in concluded that zinc is not effective for the primary prevention of early AMD [ 74 ], although zinc might reduce the risk of progression to advanced AMD.
Participants also received 2 mg copper to prevent the copper deficiency associated with high zinc intakes. After an average follow-up period of 6. Zinc supplementation alone significantly reduced the risk of developing advanced AMD in subjects at higher risk but not in the total study population.
Visual acuity loss was not significantly affected by zinc supplementation alone. Two other small clinical trials evaluated the effects of supplementation with mg zinc sulfate providing 45 mg zinc for 2 years in subjects with drusen or macular degeneration. Zinc supplementation significantly reduced visual acuity loss in one of the studies [ 76 ] but had no effect in the other [ 77 ].
Iron-deficiency anemia is a serious world-wide public health problem. Iron fortification programs have been credited with improving the iron status of millions of women, infants, and children. Fortification of foods with iron does not significantly affect zinc absorption. However, large amounts of supplemental iron greater than 25 mg might decrease zinc absorption [ 2 , 78 ].
Taking iron supplements between meals helps decrease its effect on zinc absorption [ 78 ]. High zinc intakes can inhibit copper absorption, sometimes producing copper deficiency and associated anemia [ 79 , 80 ].
For this reason, dietary supplement formulations containing high levels of zinc, such as the one used in the AREDS study [ 72 ], sometimes contain copper. Zinc toxicity can occur in both acute and chronic forms. Acute adverse effects of high zinc intake include nausea, vomiting, loss of appetite, abdominal cramps, diarrhea, and headaches [ 2 ]. One case report cited severe nausea and vomiting within 30 minutes of ingesting 4 g of zinc gluconate mg elemental zinc [ 81 ].
Intakes of — mg of zinc per day have been associated with such chronic effects as low copper status, altered iron function, reduced immune function, and reduced levels of high-density lipoproteins [ 82 ]. Long-term intakes above the UL increase the risk of adverse health effects [ 2 ]. The ULs do not apply to individuals receiving zinc for medical treatment, but such individuals should be under the care of a physician who monitors them for adverse health effects. Zinc supplements have the potential to interact with several types of medications.
A few examples are provided below. Individuals taking these medications on a regular basis should discuss their zinc intakes with their healthcare providers. Taking the antibiotic at least 2 hours before or 4—6 hours after taking a zinc supplement minimizes this interaction [ 86 ].
Zinc can reduce the absorption and action of penicillamine, a drug used to treat rheumatoid arthritis [ 87 ]. To minimize this interaction, individuals should take zinc supplements at least 2 hours before or after taking penicillamine [ 85 ].
Prolonged use of thiazide diuretics could deplete zinc tissue levels, so clinicians should monitor zinc status in patients taking these medications.
The federal government's Dietary Guidelines for Americans notes that "Nutritional needs should be met primarily from foods. Foods in nutrient-dense forms contain essential vitamins and minerals and also dietary fiber and other naturally occurring substances that may have positive health effects.
In some cases, fortified foods and dietary supplements may be useful in providing one or more nutrients that otherwise may be consumed in less-than-recommended amounts. For more information about building a healthy diet, refer to the Dietary Guidelines for Americans and the U.
Department of Agriculture's MyPlate. This fact sheet by the Office of Dietary Supplements ODS provides information that should not take the place of medical advice. We encourage you to talk to your healthcare providers doctor, registered dietitian, pharmacist, etc. Any mention in this publication of a specific product or service, or recommendation from an organization or professional society, does not represent an endorsement by ODS of that product, service, or expert advice.
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J Infect Dis ; Suppl: Plasma zinc as a predictor of diarrheal and respiratory morbidity in children in an urban slum setting. Effect of weekly zinc supplements on incidence of pneumonia and diarrhoea in children younger than 2 years in an urban, low-income population in Bangladesh: Vitamin A may help reverse a genetic predisposition to autism Vitamin B6 and magnesium improve childhood autism in combination Lowering homocysteine improved symptoms in chronic schizophrenia patients with elevated homocysteine Supplementation with essential nutrients may benefit symptoms of depression in elderly patients Elevated homocysteine associated with increased risk of mild cognitive impairment in the elderly High folate intake alongside low B status may worsen risk for dementia Vitamin B12 deficiency may affect the brain through multiple mechanisms Association with vitamin D levels and depressive symptoms.
Could early vitamin C deficiency impair development? Downside of acid drug Lack of B vitamins linked to PMS Lower blood levels of vitamin C in people with schizophrenia Study confirms homocysteine linked to brain shrinkage Vitamin and mineral supplementation improves intelligence in some American schoolchildren Vitamin D deficiency in pregnancy may have implications for mental health of children — rat study Vitamin D deficiency is associated with low mood and worse cognitive performance in older adults Vitamin D deficiency linked to Parkinson's Vitamin D linked with depression in elderly Vitamins and minerals improve learning and memory in 'normal' school children Diet has positive impact on anti-social, violent and criminal behaviour — a review Folic acid may boost baby's behaviour Iron, zinc, and lead are associated with behaviour and cognition in preschool children Sweets for kida means violent adults.
Omega-3 fatty acid EPA improves depression in people with bipolar alongside their existing medication Beta carotene helps brain function and memory Breast feeding is best food for your child's brain Depressed brain deficient in Omega-3 fatty acid DHA Dietary choline, cognitive performance and brain volume Fish consumption associated with better brain volume and memory Fish oil supplementation supports mood and brain function in the elderly Homocysteine associated with brain atrophy in the healthy elderly Omega 3 good for cognitive performance in older adults Omega-3 in pregnancy boosts baby's brain development Use it or lose it - Cognitive activity throughout life supports a healthy brain Chromium improves atypical depression Update on chromium for depression.
Cognitive performance among the elderly and dietary fish intake: Elderly people with the highest blood levels of omega-3 fatty acids had the least decline in verbal fluency Excess calcium speeds cognitive decline in the elderly Folic acid improves concentration and cognitive performance in healthy elderly Folic acid improves memory and mental agility in overs.
Higher intakes of fish oil from diet associated with slower rates of cognitive decline in elderly men Does raised homocysteine cause dementia? Acne treatment could cause depression Beneficial gut bacteria reduce anxiety and depression in mice Breakfast, Academic Performance and Mental Distress Depression linked to processed food Fish oil boosts mood in depressed seniors Folic acid improves recovery in major depression and schizophrenia Low Iron may contribute to depression in women who are not anaemic More folate may mean less depression in men.
Daniells Multivitamin and mineral supplement improves mood in hospitalised elderly Review of research suggests folate may be effective for depression Sleep deprivation may cause depression in adolescents Tryptophan supplementation induces a positive bias in processing of emotional material Cochrane Review of essential fatty acids for schizophrenia inconclusive but recommends more research needed Children with healthier diets do better in school Good food boosts school performance Poor diet associated with worse mental health in teens Schizophrenia symptoms may be helped by a gluten free, low carb diet Drug treatment for Schizophrenics may induce diabetes Fish oil may reduce psychotic disorders in high risk individuals Omega-3 fatty acid EPA helps schizophrenia symptoms Dietary sources of fat associated with schizophrenia Low essential fats worse for Schizophrenia symptoms Benefits may outweigh risks for seafood consumption in pregnancy Certain combinations of food additives are linked to hyperactivtiy in young children Food additives and hyperactivity in children Good food in infancy boosts earning power Homocysteine implicated in Schizophrenia