integrazione completa fighter

[Eagle]

mi raccomando non sottovalutate i pool vitaminici........

Solita domanda molto banale: chi, dove e come ha MAI osservato che assumere polivitaminici sia utile A CHI NON HA CARENZE?

E solita precisazione: non sto dicendo che non sia utile, sto sottlineando che non abbiamo alcuna evidenza di ciò. Può essere che lo siano come no, è come tirare le monetina.

Onestamente non ho MAI sentito nessuno che abbia notato una differenza usando polivitaminci rispetto a non usarli, e anche personalmente, benchè li utilizzi a periodi, non avverto alcun effetto e sono assolutamente consapevole che è una pratica probabilmente inutile. In caso proprio di sfiga maxima potrebbe essere addirittura nociva, cosa che ovviamente non mi auguro.


Eagle

[redlion86]

come spesso ha fatto notare anche eagle gli studi che confermano tutti questi effetti sembrano essere pochi se non nulli, a differenza di altri integratori ben più studiati

Questo non significa nulla. Gli studi scientifici sugli integratori sono veramente pochi in generale, talvolta condotti su cavie non umane a dosaggi molto differenti da quelli in etichetta e con somministrazioni differenti.
Ti cito il caso di uno studio scientifico condotto su topi che dimostrava la capacità di aumentare le resistenza. Come?
Ponendo i topi in una teca di vetro piena d'acqua e aspettando la morte per soffocamento. Si era registrato un aumento della resistenza allo sforzo.
Questi per me non sono studi scientifici che dimostrano nulla. Mentre par altri sono un fattore da prendere in considerazione.
Come del resto, non dimostra nulla nemmeno un singolo studio scientifico, ma dimostra i risvolti di una valutazione condotta in casi specifici.
E' il caso dell'arginina che viene studiata scientificamente in soluzione endovenosa a dosi di circa 20 volte il consumo tipico.

Non bisogna nascondersi sempre dietro ad un dito. Ci sono degli studi che analizzano tantissimi fattori utili per gli sportivi: diete, integrazione, tipi di allenamento e risposta fisica, ma non per questo un metodo non è valido solo ed esclusivamente perchè il campo della ricerca non ci è ancora arrivato.

Io stesso mi ritrovo ad avere idee contrastanti su questo argomento, ma onestamente quando mi scontro con la mancanza di informazione (soprattutto l'informazione libera) mi pongo sempre le stesse domande:
-perchè per me ha funzionato?
-perchè non esistono studi al riguardo?
-perchè ora che l'ho fatto provare a 10 persone 8 hanno avuto benefici?
-come mi devo comportare se divulgo questo mio caso?

E da qui che arrivo a citare il caso dei pool vitaminici. Compresse di vitamine e minerali per me sono importantissimi per un fighter, a prescindere dalla temporanea carenza o malattia, o stato di affaticamento.
Il motivo è da ricercare negli allenamenti che talvolta si fanno frequentissimi e intensi, in aggiunta a diete per il controllo del peso.
Come posso aspettare la necessità vera e cioè la carenza quando in realtà con banali accorgimenti posso garantire un'efficienza duratura all'organismo.

Ebbene io nel mio caso assumo costantemente vitC in aggiunta a VIT&MIN. Nessuno studio mi dice che quel che faccio è corretto o no, se non un po' di letteratura medica che si trova qua e la in rete e in biblioteca. Adesso come dovrei comportarmi? Smettere con l'assunzione perchè nessuno mi conferma quel che sento io e magari aspettare una carenza vera e propria, oppure continuare tranquillamente l'assunzione e permettere al mio organismo di stare bene (con la somma di tanti accorgimenti) e poterlo stressare per 9 sessioni settimanali?

Io una risposta a quate domande me la sono già data. A voi la scelta nel vostro specifico caso.

[Eagle]

Questo non significa nulla. Gli studi scientifici sugli integratori sono veramente pochi in generale, talvolta condotti su cavie non umane a dosaggi molto differenti da quelli in etichetta e con somministrazioni differenti.
Ti cito il caso di uno studio scientifico condotto su topi che dimostrava la capacità di aumentare le resistenza. Come?
Ponendo i topi in una teca di vetro piena d'acqua e aspettando la morte per soffocamento. Si era registrato un aumento della resistenza allo sforzo.
Questi per me non sono studi scientifici che dimostrano nulla. Mentre par altri sono un fattore da prendere in considerazione.
Come del resto, non dimostra nulla nemmeno un singolo studio scientifico, ma dimostra i risvolti di una valutazione condotta in casi specifici.
E' il caso dell'arginina che viene studiata scientificamente in soluzione endovenosa a dosi di circa 20 volte il consumo tipico.

Non bisogna nascondersi sempre dietro ad un dito. Ci sono degli studi che analizzano tantissimi fattori utili per gli sportivi: diete, integrazione, tipi di allenamento e risposta fisica, ma non per questo un metodo non è valido solo ed esclusivamente perchè il campo della ricerca non ci è ancora arrivato.

Io stesso mi ritrovo ad avere idee contrastanti su questo argomento, ma onestamente quando mi scontro con la mancanza di informazione (soprattutto l'informazione libera) mi pongo sempre le stesse domande:
-perchè per me ha funzionato?
-perchè non esistono studi al riguardo?
-perchè ora che l'ho fatto provare a 10 persone 8 hanno avuto benefici?
-come mi devo comportare se divulgo questo mio caso?

E da qui che arrivo a citare il caso dei pool vitaminici. Compresse di vitamine e minerali per me sono importantissimi per un fighter, a prescindere dalla temporanea carenza o malattia, o stato di affaticamento.
Il motivo è da ricercare negli allenamenti che talvolta si fanno frequentissimi e intensi, in aggiunta a diete per il controllo del peso.
Come posso aspettare la necessità vera e cioè la carenza quando in realtà con banali accorgimenti posso garantire un'efficienza duratura all'organismo.

Ebbene io nel mio caso assumo costantemente vitC in aggiunta a VIT&MIN. Nessuno studio mi dice che quel che faccio è corretto o no, se non un po' di letteratura medica che si trova qua e la in rete e in biblioteca. Adesso come dovrei comportarmi? Smettere con l'assunzione perchè nessuno mi conferma quel che sento io e magari aspettare una carenza vera e propria, oppure continuare tranquillamente l'assunzione e permettere al mio organismo di stare bene (con la somma di tanti accorgimenti) e poterlo stressare per 9 sessioni settimanali?

Io una risposta a quate domande me la sono già data. A voi la scelta nel vostro specifico caso.

Ogniuno ha il proprio approccio, quello che non va bene è scrivere che per un fighter sono importanti i multivitaminici, a meno che non si specifichi che è una personale opnione, basata su osservazioni personali.

Altrimenti sembra che ci sia un consenso, che NON C'E', sul fatto che sia importante assumere multivitaminici se si fa uno sport da combattimento.

Magari prima o poi ci sarà, consenso su questa cosa, magari anche basato su osservazioni fatte in modo corretto (leggi metodo scientifico), ma per ora non c'è.

Di studi sugli integratori ce ne sono, non tanti, non sempre fatti su chi si alleano con i pesi (sui fighters non lo so perchè non me ne interesso), ma qualche cosa c'è.
Il vantaggio di uno studio è che ha un metodo, controllato, discusso, che deve passare un comintato etico, una revisione prima di accettarlo per la pubblicazione. Quindi una serie di controlli che ne garantiscono la qualità.

Se io dico a 10 persone di assumere l'integratore X e 8 di queste, dopo 2 mesi mi dicono che si sono trovate bene ... spero concorderai che l'informazione e la garanzia che in quella informazione ci sia qualche cosa di "reale" è decisamente inferiore che in uno studio scientifico.

Ovviamente PER IL SINGOLO la cose sono diverse, ma il campo di applicazione rimane SOLO SE STESSO, e nel campo di applicazione DEFINITO (temporalmente e in relazione a tutti gli altri fattori).

Ovvero, se IO, prendendo multivitaminici, divento un toro, e non riporto effetti negativi, PER ME, QUEL MULTIVITAMINICO, IN QUELLE DOSI, IN QEL MOMENTO, IN QUELLE CONDIZIONI DI DIETA, ALLENAMENTO, ETC ETC ETC ... HA FATTO QUEGLI EFFETTI.


Eagle

[Eagle]

Questo è consultatbile anche in formato intero

NIH Consens State Sci Statements. 2006 May 15-17;23(2):1-30. Links

NIH State-of-the-Science Conference Statement on Multivitamin/Mineral Supplements and Chronic Disease Prevention.

[No authors listed] National Institutes of Health, Office of the Director, Bethesda, MD 20892, USA.
OBJECTIVE: To provide health care providers, patients, and the general public with a responsible assessment of currently available data on Multivitamin/Mineral Supplements and Chronic Disease Prevention. PARTICIPANTS: A non-DHHS, non-advocate 13-member panel included experts in the fields of food science and human nutrition, biostatistics, biochemistry, toxicology, geriatric medicine, family medicine, pediatrics and pediatric endocrinology, cancer prevention, epidemiology, disease prevention and health promotion, and consumer protection. In addition, 19 experts from pertinent fields presented data to the panel and conference audience. EVIDENCE: Presentations by experts and a systematic review of the literature prepared by The Johns Hopkins University Evidence-based Practice Center, through the Agency for Healthcare Research and Quality. Scientific evidence was given precedence over anecdotal experience. CONFERENCE PROCESS: The panel drafted its statement based on scientific evidence presented in open forum and on published scientific literature. The draft statement was presented on the final day of the conference and circulated to the audience for comment. The panel released a revised statement later that day at Upcoming Conferences. This statement is an independent report of the panel and is not a policy statement of the NIH or the Federal Government. CONCLUSIONS: Use of multivitamins/minerals (MVMs) has grown rapidly over the past several decades, and dietary supplements are now used by more than half of the adult population in the United States. In general, MVMs are used by individuals who practice healthier lifestyles, thus making observational studies of the overall relationship between MVM use and general health outcomes difficult to interpret. Despite the widespread use of MVMs, we still have insufficient knowledge about the actual amount of total nutrients that Americans consume from diet and supplements. This is at least in part due to the fortification of foods with these nutrients, which adds to the effects of MVMs or single-vitamin or single-mineral supplements. Historically, fortification of foods has led to the remediation of vitamin and mineral deficits, but the cumulative effects of supplementation and fortification have also raised safety concerns about exceeding upper levels. Thus, there is a national need to improve the methods of obtaining accurate and current data on the public's total intake of these nutrients in foods and dietary supplements. In systematically evaluating the effectiveness and safety of MVMs in relation to chronic disease prevention, we found few rigorous studies on which to base clear conclusions and recommendations. Most of the studies we examined do not provide strong evidence for beneficial health-related effects of supplements taken singly, in pairs, or in combinations of three or more. Within some studies or subgroups of the study populations, there is encouraging evidence of health benefits, such as increased bone mineral density and decreased fractures in postmenopausal women who use calcium and vitamin D supplements. However, several other studies also provide disturbing evidence of risk, such as increased lung cancer risk with beta-carotene use among smokers. The current level of public assurance of the safety and quality of MVMs is inadequate, given the fact that manufacturers of these products are not required to report adverse events and the FDA has no regulatory authority to require labeling changes or to help inform the public of these issues and concerns. It is important that the FDA's purview over these products be authorized and implemented. Finally, the present evidence is insufficient to recommend either for or against the use of MVMs by the American public to prevent chronic disease. The resolution of this important issue will require advances in research and improved communication and collaboration among scientists, health care providers, patients, the pharmaceutical and supplement industries, and the public.

[Eagle]

Questo è simile

NIH Consens State Sci Statements. 2006 May 15-17;23(2):1-30. Links

NIH State-of-the-Science Conference Statement on Multivitamin/Mineral Supplements and Chronic Disease Prevention.

[No authors listed] National Institutes of Health, Office of the Director, Bethesda, MD 20892, USA.
OBJECTIVE: To provide health care providers, patients, and the general public with a responsible assessment of currently available data on Multivitamin/Mineral Supplements and Chronic Disease Prevention. PARTICIPANTS: A non-DHHS, non-advocate 13-member panel included experts in the fields of food science and human nutrition, biostatistics, biochemistry, toxicology, geriatric medicine, family medicine, pediatrics and pediatric endocrinology, cancer prevention, epidemiology, disease prevention and health promotion, and consumer protection. In addition, 19 experts from pertinent fields presented data to the panel and conference audience. EVIDENCE: Presentations by experts and a systematic review of the literature prepared by The Johns Hopkins University Evidence-based Practice Center, through the Agency for Healthcare Research and Quality. Scientific evidence was given precedence over anecdotal experience. CONFERENCE PROCESS: The panel drafted its statement based on scientific evidence presented in open forum and on published scientific literature. The draft statement was presented on the final day of the conference and circulated to the audience for comment. The panel released a revised statement later that day at Upcoming Conferences. This statement is an independent report of the panel and is not a policy statement of the NIH or the Federal Government. CONCLUSIONS: Use of multivitamins/minerals (MVMs) has grown rapidly over the past several decades, and dietary supplements are now used by more than half of the adult population in the United States. In general, MVMs are used by individuals who practice healthier lifestyles, thus making observational studies of the overall relationship between MVM use and general health outcomes difficult to interpret. Despite the widespread use of MVMs, we still have insufficient knowledge about the actual amount of total nutrients that Americans consume from diet and supplements. This is at least in part due to the fortification of foods with these nutrients, which adds to the effects of MVMs or single-vitamin or single-mineral supplements. Historically, fortification of foods has led to the remediation of vitamin and mineral deficits, but the cumulative effects of supplementation and fortification have also raised safety concerns about exceeding upper levels. Thus, there is a national need to improve the methods of obtaining accurate and current data on the public's total intake of these nutrients in foods and dietary supplements. In systematically evaluating the effectiveness and safety of MVMs in relation to chronic disease prevention, we found few rigorous studies on which to base clear conclusions and recommendations. Most of the studies we examined do not provide strong evidence for beneficial health-related effects of supplements taken singly, in pairs, or in combinations of three or more. Within some studies or subgroups of the study populations, there is encouraging evidence of health benefits, such as increased bone mineral density and decreased fractures in postmenopausal women who use calcium and vitamin D supplements. However, several other studies also provide disturbing evidence of risk, such as increased lung cancer risk with beta-carotene use among smokers. The current level of public assurance of the safety and quality of MVMs is inadequate, given the fact that manufacturers of these products are not required to report adverse events and the FDA has no regulatory authority to require labeling changes or to help inform the public of these issues and concerns. It is important that the FDA's purview over these products be authorized and implemented. Finally, the present evidence is insufficient to recommend either for or against the use of MVMs by the American public to prevent chronic disease. The resolution of this important issue will require advances in research and improved communication and collaboration among scientists, health care providers, patients, the pharmaceutical and supplement industries, and the public.

[Eagle]

continuo per qualche post ancora

Ann Intern Med. 2003 Jul 1;139(1):56-70. Links

Comment in: Ann Intern Med. 2003 Jul 1;139(1):I-76. Routine vitamin supplementation to prevent cardiovascular disease: a summary of the evidence for the U.S. Preventive Services Task Force.

Morris CD, Carson S.
Department of Medical Informatics and Clinical Epidemiology, Oregon Health & Science University Evidence-based Practice Center, 3181 SW Sam Jackson Park Road, Mail Code BICC, Portland, OR 97239, USA.
BACKGROUND: Antioxidant vitamins are thought to play a role in atherosclerosis. Supplementation of these nutrients has been explored as a means of reducing cardiovascular morbidity and mortality. PURPOSE: To assess the evidence of the effectiveness of vitamin supplementation, specifically vitamins A, C, and E; beta-carotene; folic acid; antioxidant combinations; and multivitamin supplements, in preventing cardiovascular disease. DATA SOURCES: Cochrane Controlled Trials Registry and MEDLINE (1966 to September 2001), reference lists, and experts. STUDY SELECTION: The researchers selected English-language reports of randomized trials and cohort studies that assessed vitamin supplementation in western populations and reported incidence of or death from cardiovascular events. They also included reports of good- or fair-quality clinical trials of primary and secondary prevention and good- or fair-quality prospective cohort studies. Studies that examined only dietary nutrients or did not provide separate estimates for supplements were not included. DATA EXTRACTION: Two reviewers abstracted descriptive information and data on cardiovascular outcomes and mortality from included studies. The researchers assessed study quality using predetermined criteria. DATA SYNTHESIS: Evidence tables were constructed to summarize data from included studies. The researchers summarized the strength, level, and quality of the overall evidence for the effectiveness of each of the vitamin supplements in preventing or treating cardiovascular disease. CONCLUSIONS: Some good-quality cohort studies have reported an association between the use of vitamin supplements and lower risk for cardiovascular disease. Randomized, controlled trials of specific supplements, however, have failed to demonstrate a consistent or significant effect of any single vitamin or combination of vitamins on incidence of or death from cardiovascular disease. Understanding the sources of these differences will permit researchers to better analyze the cohort study data and to better design long-term clinical trials.

[Eagle]

Am J Clin Nutr. 2007 Jan;85(1):314S-317S. Links

Clinical trials of vitamin and mineral supplements for cancer prevention.

Greenwald P, Anderson D, Nelson SA, Taylor PR.
Division of Cancer Prevention, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-7309, USA. pg37g@nih.gov
Approximately 20-30% of Americans consume multivitamin supplements daily, indicating high public interest in the prevention of cancer and other chronic diseases through a nutrition-based approach. Although several bioactive food components, including vitamins and minerals, have been investigated for their ability to affect cancer risk, few large, randomized, placebo-controlled clinical trials of multivitamins with cancer as the primary endpoint have been performed. The results of most large-scale trials of multivitamin supplements (combinations of > or = 2 vitamins and minerals) to prevent cancer have been mixed. The Linxian General Population and Dysplasia trials found a decreased risk of cancer, particularly stomach cancer, for participants taking a multivitamin supplement, but this was in a borderline-deficient population in China. Two trials, the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study and the beta-Carotene and Retinol Efficacy Trial, found an increased risk of lung cancer among male cigarette smokers or asbestos-exposed persons taking beta-carotene-a surprising result, considering that most epidemiologic studies have suggested that consumption of fruit and vegetables appears to lower cancer risk. To clarify the effects of multivitamin supplements, several large randomized clinical trials are underway, including the Physicians' Health Study II, the Selenium and Vitamin E Cancer Prevention Trial, and a European study, Supplémentation en Vitamines et Minéraux Antioxydants (SU.VI. MAX). Because epidemiologic studies generally evaluate foods rather than specific bioactive food components, a systematic approach to determining how combinations of vitamins and minerals may interact to ameliorate cancer risk is necessary to further our understanding of the potential benefits and risks of supplement use.
PMID: 17209217 [PubMed - indexed for MEDLINE]

[Eagle]

In Danimarca non hanno osservato benefici con i multivitaminici in persone sane.


Ugeskr Laeger. 2006 May 22;168(21):2051-8. Links

[Should healthy people take a daily vitamin pill?]

[Article in Danish]


Ovesen LF.
Hjerteforeningen, Hauser Plads 10, DK-1127 København K. lovesen@hjerteforeningen.dk
About 50% of the Danish population take a daily multivitamin-mineral (MVM) supplement despite the demonstration that the dietary intake of vitamins and minerals is sufficient to cover the needs of most healthy Danes. This systematic review, which includes prospective studies of the significance of MVM in disease risk as well as in other somatic and mental functions in humans, does not find evidence of a beneficial effect of vitamin and mineral supplementation in the healthy Danish population.

[Eagle]

Questi (ed è una review ), hanno addirittura trovato una aumentata incidenza di food allergies nei consumatori di multivitaminici...

Curr Allergy Asthma Rep. 2007 Jun;7(3):182-6. Links

Risk factors for the development of food allergy.

Kaza U, Knight AK, Bahna SL.
Allergy and Immunology Section, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130, USA. sbahna@lsuhsc.edu
Both genetic and environmental factors seem to predispose to the development of food allergy. A most notable factor is diet, particularly during infancy. Possible other factors include maternal diet during pregnancy and lactation, birth by cesarean section, exposure to tobacco smoke, multivitamin supplementation, and intake of antacids. It is important to identify and control such risk factors to reduce the development of food allergy.

[Eagle]

Questi sono preoccupati per l'osservazione che chi consuma multivitaminici potrebbe avere un aumentato rischio di cancro prostatico (stadi avanzato e mortale)...


J Natl Cancer Inst. 2007 May 16;99(10):754-64. Links

Comment in: J Natl Cancer Inst. 2007 May 16;99(10):742-3. J Natl Cancer Inst. 2007 Oct 3;99(19):1491-2; author reply 1492-3. Nutr Cancer. 2008 Jan-Feb;60(1):1-6. Multivitamin use and risk of prostate cancer in the National Institutes of Health-AARP Diet and Health Study.

Lawson KA, Wright ME, Subar A, Mouw T, Hollenbeck A, Schatzkin A, Leitzmann MF.
Division of Cancer Prevention, National Cancer Institute, Bethesda, MD, USA. lawsonka@mail.nih.gov
BACKGROUND: Multivitamin supplements are used by millions of Americans because of their potential health benefits, but the relationship between multivitamin use and prostate cancer is unclear. METHODS: We prospectively investigated the association between multivitamin use and risk of prostate cancer (localized, advanced, and fatal) in 295,344 men enrolled in the National Institutes of Health (NIH)-AARP Diet and Health Study who were cancer free at enrollment in 1995 and 1996. During 5 years of follow-up, 10,241 participants were diagnosed with incident prostate cancer, including 8765 localized and 1476 advanced cancers. In a separate mortality analysis with 6 years of follow-up, 179 cases of fatal prostate cancer were ascertained. Multivitamin use was assessed at baseline as part of a self-administered, mailed food-frequency questionnaire. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated by use of Cox proportional hazards regression, adjusted for established or suspected prostate cancer risk factors. RESULTS: No association was observed between multivitamin use and risk of localized prostate cancer. However, we found an increased risk of advanced and fatal prostate cancers (RR = 1.32, 95% CI = 1.04 to 1.67 and RR = 1.98, 95% CI = 1.07 to 3.66, respectively) among men reporting excessive use of multivitamins (more than seven times per week) when compared with never users. The incidence rates per 100,000 person-years for advanced and fatal prostate cancers for those who took a multivitamin more than seven times per week were 143.8 and 18.9, respectively, compared with 113.4 and 11.4 in never users. The positive associations with excessive multivitamin use were strongest in men with a family history of prostate cancer or who took individual micronutrient supplements, including selenium, beta-carotene, or zinc. CONCLUSION: These results suggest that regular multivitamin use is not associated with the risk of early or localized prostate cancer. The possibility that men taking high levels of multivitamins along with other supplements have increased risk of advanced and fatal prostate cancers is of concern and merits further evaluation.

[Eagle]

Questo (è un altro gruppo rispetto a quello del post precendente) hanno anche loro trovato una associazione tra ca prostatico mortale e multivitaminici...

Cancer Causes Control. 2005 Aug;16(6):643-50. Links

Use of multivitamins and prostate cancer mortality in a large cohort of US men.

Stevens VL, McCullough ML, Diver WR, Rodriguez C, Jacobs EJ, Thun MJ, Calle EE.
Department of Epidemiology and Surveillance Research, American Cancer Society, 1599 Clifton Road NE, Atlanta, GA 30329, USA. Victoria.Stevens@cancer.org
OBJECTIVE: To assess the association between the use of multivitamins and prostate cancer mortality. METHODS: A total of 5585 deaths from prostate cancer were identified during 18 years of follow-up of 475,726 men who were cancer-free and provided complete information on multivitamin use at enrollment in the Cancer Prevention Study II (CPS-II) cohort in 1982. Cox proportional hazards modeling was used to measure the association between multivitamin use at baseline and death from prostate cancer and to adjust for potential confounders. RESULTS: The death rate from prostate cancer was marginally higher among men who took multivitamins regularly (> or =15 times/month) compared to non-users (multivariate rate ratio=1.07, 95% CI: 0.99-1.15); this risk was statistically significant only for those multivitamin users who used no additional (vitamin A, C, or E) supplements (multivariate rate ratio=1.15, 95% CI: 1.05-1.26). In addition, risk was greatest during the initial four years of follow-up (1982-1986, multivariate rate ratio=1.12, 95 CI: 0.87-1.46). CONCLUSIONS: Regular multivitamin use was associated with a small increase in prostate cancer death rates in our study, and this association was limited to a subgroup of users.

[Eagle]

Ultimo, è una review, in cui i risultati sono dubbi = ci vogliono altri studi.

J Hum Nutr Diet. 2006 Jun;19(3):179-90. Links

A systematic review of multivitamin and multimineral supplementation for infection.

Stephen AI, Avenell A.
The Health Services Research Unit, University of Aberdeen, Aberdeen, UK. a.i.stephen@rgu.ac.uk
BACKGROUND: Infections are major causes of morbidity and mortality worldwide. Micronutrients have important functions in the body's immune system. This systematic review examined the evidence from randomized controlled trials (RCTs) on whether multivitamin and multimineral supplementation is effective in reducing infection. METHODS: Electronic databases searched: Cochrane Controlled Trials Register, EMBASE, MEDLINE, BIOSIS, CAB abstracts. Hand searching of nutrition journals and reference lists was carried out. RCTs and quasi-randomized trials of supplementation of adults with at least two vitamins or minerals or a combination were selected. Study results were combined in meta-analysis plots where appropriate. RESULTS: Twenty studies were included in the review. Small numbers were available for each meta-analysis. Results are presented here without the Chandra group studies. No significant difference was found in the number of episodes of infection in older people (>or = 65 years) between those supplemented and those not supplemented; (WMD) 0.06 [95% confidence interval (CI) -0.04, 0.16], P = 0.25. In other adults groups, there were significantly less episodes of infection in those supplemented; (WMD) -1.20 (95% CI -2.08, -0.32), P = 0.008. There was no significant difference between those older people supplemented and those not supplemented in the number with at least one infection; relative risk (RR) 0.98 (95% CI 0.86, 1.11), P = 0.77. Similarly, there was no significant difference in the numbers in other adult groups who had at least one episode of infection between those supplemented and those taking placebo; (RR) 0.81 (95% CI 0.65, 1.00), P = 0.06. Subgroup analyses suggested that supplemented people aged 65 years or over may benefit more if they are undernourished and supplemented for over 6 months, WMD -0.67 infections (95% CI -1.24, -0.10), P = 0.02. CONCLUSION: Further large trials are needed, particularly in undernourished older people. Trials of supplementation periods of over 6 months are recommended.

[redlion86]

Non ho tempo a sufficienza per risponderti, prometto che appena avrò letto gli studi (o almeno gli abstract postati) ti darò la mia opinione.

Per quel che ho visto di sfuggita posso dirti che sembra interessante, capire la correlazione con le eventuali insorgenze di malattie. Ma mi pare che non ci si riferisca a soggetti sportivi.
Comunque tralascio le argomenazioni superficiali e rimando ad una lettura più attenta.

Per ora ti ringrazio per lo spunto di discussione.

[DANIELS]

EAGLE mi sorprendi sempre

[Eagle]

Questa breve carrellata è solo per far vedere che le conclusioni REALI sono veramente poche, se non nulle. Ci sono anche possibili problemi.


La mia personale impressione è che:

- siano utili in caso di carenze, più o meno manifeste (anziani, malati, malnutriti, etc etc);

- in alcuni casi ci sono state delle brutte sorprese (aumento dei cancri al polmone, aumento della mortalità da cancro alla prostata);

- effetti benefici in sportivi sani, qualche volta evidenziati, ma in "secondary outcomes", ovvero in misurazioni da laboratorio, molto raramente in performances o composizione corporea .


Il buon senso dovrebbe farmi concludere che, dati i possibili sia pur piccoli rischi, e i non dimostrati benefici, val la pena di provare i multivitaminici, ma se non succede niente di buono, non vedo perchè continuare nell'assumere un qualche cosa che non mi fa niente e potrebbe, alla lunga, anche farmi del danno.


Ma sono idee che cancello rapidamente, e torno alla mentalità bovina di Arnold "tutto, in dosi massicce, e spesso. Così quando serve son sicuro che c'è"...


Eagle