Quitosana + Termo

[johntraceur]

quitosana + termo

Boa tarde

Desculpe se postei na área errada preciso perder peso e
andei pesquisando um pouco, entretanto nao achei nada sobre o uso de quitosana junto com termogenicos.
gostaria de saber se tem algum problema tomar um quitosana 500mg mais um termogenico, ou Oxyelite Pro, que esta com um rating bom na bodybuilding ou lipo 6black. Alem disso, para evitar um perdo muito grande na massa magra, estava pensando em tomar o whey tambem junto com uma dieta hipocalorica.
Gostaria de opinoes sobre o uso desses produtos juntos. Quitosana + Termogenico + Whey

Editado Abril 9, 2013 às 16:42 por johntraceur

[Visitante usuario_excluido22s]

Não tem nenhuma contra-indicação, mas a quitosona tem eficácia muito superior ao termogênico.

Além do mais, ela pode ser tomada por períodos muito longos e o único efeito colateral potencial (mas não comum) é diarréia.

Em pacientes com sobrepeso e comparada ao placebo, a quitosana reduz em média 3.28 kg de peso em 28 dias.

[mpcosta82]

Não tem nenhuma contra-indicação, mas a quitosona tem eficácia muito superior ao termogênico.

Além do mais, ela pode ser tomada por períodos muito longos e o único efeito colateral potencial (mas não comum) é diarréia.

Em pacientes com sobrepeso e comparada ao placebo, a quitosana reduz em média 3.28 kg de peso em 28 dias.

Olá,

você tem a fonte deste estudo?

[Visitante usuario_excluido22s]

Copyright: The Cochrane Library

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Chitosan as a treatment for body weight reduction: a meta-analysis (Structured abstract)

ErnstE, PittlerM H, . Chitosan as a treatment for body weight reduction: a meta-analysis. Perfusion 1998;11(11) :461-465.

Authors' objectives

The authors aimed to critically review evidence that chitosan leads to weight reduction in overweight or obese patients.

Searching

MEDLINE, EMBASE, BIOSIS Previews, CISCOM and the Cochrane Library were searched from their inception to January 1998 for randomised controlled trials (RCTs) on the use of chitosan for obesity, using the terms 'chitosan', 'chitin' and 'Fat Magnets'. In addition, manufacturers of chitosan products were contacted for published and unpublished material, the authors' own library was searched, and references of studies were scanned to identify further studies. There was no restriction on language of publication.

Study selection: study designs

Randomised, placebo-controlled, double-blind trials were included.

Study selection: specific interventions

Administration of chitosan or identical placebo (4 tablets/day) either in conjunction with dietary intervention (hypocaloric diet of 1000 to 1200 kcalories/day) or without. Controls received placebo and dietary intervention, whilst cases received chitosan alone or with dietary intervention. Evaluations where chitosan was not the main active constituent were excluded.

Study selection: participants

Patients who were overweight or obese (between 10 to 25% excess weight), or who were overweight or obese and had hyperlipidaemia (hyperlipidaemia was not defined).

Study selection: outcomes

The outcome assessed in this review was mean body weight reduction in kg. The outcomes included in the individual studies were body weight, blood-pressure, blood lipids, body fat and skinfold thickness.

Study selection: how were decisions on the relevance of primary studies made?

Two reviewers assessed methodological quality, trial outcomes and details of the investigation in a pre-defined fashion.

The predefined criteria are not detailed in the review, with the exception of the methodological quality assessment and the stated focus on RCTs in overweight or obese patients with chitosan treatment as the main intervention. Studies had to be published in peer-reviewed journals to be included in the review.

Validity assessment

The methodological quality of the identified studies was assessed using a scoring system developed by Jadad et al. (See Other Publications of Related Interest). A point was given for each of the following criteria if they were met:

1. The study was described as randomised and included the use of words such as 'random', 'randomly' and 'randomisation'.

2. The study was described as double-blind.

3. Withdrawals and drop-outs were described.

4. The method of randomisation was described and appropriate (e.g. random number tables or computer-generated).

5. The method of double-blinding was described as appropriate (e.g. identical placebo, active placebo, dummy).

In addition one point was deducted if:

6. The method of randomisation was described and inappropriate (e.g. alternate allocation or allocation by date of birth, hospital number).

7. If the method of double-blinding was described and inappropriate (comparison of tablet versus injection with no double dummy).

A maximum of 5 points could be achieved. In terms of methodological quality, papers were given a score of a maximum of 5 points. The assessment was carried out by two independent reviewers and any disagreements were resolved by discussion.

Data extraction

The authors present data on study design, sample size and drop-outs, active therapy, control treatment, treatment period, end points, results and adverse effects.

Methods of synthesis: how were the studies combined?

The trial results were pooled and analysed by meta-analysis using RevMan 3.01 software. A random-effects model was used to calculate the weighted mean difference and 95% confidence intervals (CIs).

Methods of synthesis: how were differences between studies investigated?

Heterogeneity between the studies was not assessed in this review.

Results of the review

In total, 386 patients across 5 studies were examined.

Four studies satisfied all five criteria of the methodology score. They contributed 100, 90, 86 and 80 patients respectively to the analysis. One paper scored 4 points and contributed 30 patients. The weighted mean difference between intervention and placebo groups was 3.28 kg (95% CI: 1.5,5.1) after 28 days. The authors suggest that a statistically-significant and clinically-relevant difference between the groups is achieved when chitosan is given orally as an adjunct to a hypocaloric diet.

Authors' conclusions

The meta-analysis implies that the mean difference in terms of weight reduction between chitosan and placebo is 3.28 kg after 28 days of treatment. This result has to be viewed with caution as concerns have been raised about the original studies. Rigorous independent trials are required to assess the clinical effectiveness of chitosan as a means of weight reduction.

CRD commentary

The review addresses an important clinical and public health question, and a rigorous and comprehensive literature search without language restrictions was conducted. Some study selection criteria were presented, e.g. RCTs of obese patients with chitosan as the main intervention. The authors used an established checklist for assessing methodological quality and individual study details were tabulated. Two independent reviewers assessed the studies but it is unclear how many researchers were involved in data extraction. The methods used to pool and analyse the data were appropriate, although heterogeneity was not assessed. The authors point out that all trials included in this study were published in the same journal, and they have reservations about the fact that these studies were not found on any of the searched databases but retrieved from one manufacturer of chitosan preparations. Potential problems with the original studies include the combination of chitosan intervention with a hypocaloric diet. The authors argue that the diet may have confounded the results although they fail to mention in what way. The authors therefore have reservations about the strength of evidence based on these trials.

Implications of the review for practice and research

Practice: Chitosan seems to be an effective treatment to achieve weight reduction in overweight and obese patients. This is important in the light of a growing obesity epidemic and the known link between obesity and serious health risks.

Research: Whether chitosan is truly effective cannot be conclusively answered by this review. There is a need for independent high-quality clinical trials.

Other publications of related interest

Jadad AR, Moore RA, Carroll D, Jenkinson C, Reynolds DJ, Gavaghan DJ, et al. Assessing the quality of reports of randomized clinical trials: is blinding necessary? Control Clin Trials 1996;17:1-12.

Record status

This record is a structured abstract written by CRD reviewers. The original has met a set of quality criteria. Since September 1996 abstracts have been sent to authors for comment. Additional factual information is incorporated into the record. Noted as [A:....].

CRD database number

DARE-11999000080

Index terms

Subject index terms

Subject indexing assigned by NLM: Medical Subject Headings (MeSH): Chitin; Obesity[drug therapy]; Weight Loss

CRD database number: DARE11999000080

Copyright: The Cochrane Library

---

Atualizada com effect size menor em

Ni Mhurchu C, Dunshea-Mooij CA, Bennett D, Rodgers A. Chitosan for overweight 
or obesity. Cochrane Database Syst Rev. 2005 Jul 20;(3):CD003892. Review. Update 
in: Cochrane Database Syst Rev. 2008;(3):CD003892. 

Essa última temos acesso gratuito pela bireme.

[mpcosta82]

Ah, não precisava ter colocado todo o texto, bastaria o link

É importante ressaltar o que os autores da meta-análise falam logo após "Em pacientes com sobrepeso e comparada ao placebo, a quitosana reduz em média 3.28 kg de peso em 28 dias": "Este resultado deve ser visto com cautela, uma vez que foram levantados questionamentos a respeito dos estudos originais. Estudos independentes rigorosos são requeridos para verificar a eficiência clínica da quitosana como meio de redução de peso".

Por exemplo, um estudo conforme estes parâmetros foi feito em 2004:

http://www.ncbi.nlm.nih.gov/pubmed/15311218
The effect of the dietary supplement, Chitosan, on body weight: a randomised controlled trial in 250 overweight and obese adults

BJECTIVE:
To evaluate the efficacy of chitosan for weight loss in overweight and obese adults.
DESIGN AND SETTING:
A 24-week randomised, double-blind, placebo-controlled trial, conducted at the University of Auckland between November 2001 and December 2002.
PARTICIPANTS:
A total of 250 participants (82% women; mean (s.d.) body mass index, 35.5 (5.1) kg/m(2); mean age, 48 (12) y)
INTERVENTIONS:
Participants were randomly assigned to receive 3 g chitosan/day (n=125) or placebo (n=125). All participants received standardised dietary and lifestyle advice for weight loss. Adherence was monitored by capsule counts.
MAIN OUTCOME MEASURES:
The primary outcome measure was change in body weight. Secondary outcomes included changes in body mass index, waist circumference, body fat percentage, blood pressure, serum lipids, plasma glucose, fat-soluble vitamins, faecal fat, and health-related quality of life.
RESULTS:
In an intention-to-treat analysis with the last observation carried forward, the chitosan group lost more body weight than the placebo group (mean (s.e.), -0.4 (0.2) kg (0.4% loss) vs +0.2 (0.2) kg (0.2% gain), P=0.03) during the 24-week intervention, but effects were small. Similar small changes occurred in circulating total and LDL cholesterol, and glucose (P<0.01). There were no significant differences between groups for any of the other measured outcomes.
CONCLUSION:
In this 24-week trial, chitosan treatment did not result in a clinically significant loss of body weight compared with placebo.

Outro estudo desse tipo, de 1999:

http://www.ncbi.nlm.nih.gov/pubmed/10369493

Randomized, double-blind trial of chitosan for body weight reduction.

Pittler MH, Abbot NC, Harkness EF, Ernst E.

Source

Department of Complementary Medicine, School of Postgraduate Medicine and Health Sciences, University of Exeter, United Kingdom.

Abstract

BACKGROUND:

Overweight and obesity is a prevalent and costly threat to public health. Compelling evidence links overweight and obesity with serious disorders such as cardiovascular diseases and diabetes. Dietary regimen are notoriously burdened with poor compliance. Chitosan is promoted in the US and other countries as an oral remedy to reduce fat absorption and has now been incorporated as a major constituent into several over-the-counter remedies. The primary aim of this study is to investigate the clinical effectiveness of oral chitosan for body weight reduction.

METHODS:

Thirty-four overweight volunteers were included in a randomized placebo-controlled double-blind trial. Subjects were assigned to receive either four capsules of chitosan or indistinguishable placebo twice daily for 28 consecutive days. Measurements were taken at baseline, after 14 and 28d of treatment. Subjects maintained their normal diet and documented the type and amount of food consumed. Adverse effects were assessed and compliance monitored.

RESULTS:

Data from 30 subjects were entered into an intention-to-treat analysis. After four weeks of treatment, body mass index, serum cholesterol, triglycerides, vitamin A, D, E and beta-carotene were not significantly different in subjects receiving chitosan compared to those receiving placebo. Vitamin K was significantly increased after four weeks in the chitosan group compared with placebo (P<0.05). Compliance was 91.5% and 96.0% for chitosan and placebo groups respectively.

CONCLUSION:

The above data suggest that chitosan in the administered dosage, without dietary alterations, does not reduce body weight in overweight subjects. No serious adverse effects were reported.

Uma meta-análise mais recente, de 2005, analisou diversos estudos, e separou eles em "alta qualidade" e "baixa qualidade". Os resultados são mostrados abaixo.

http://www.ncbi.nlm.nih.gov/pubmed/15655037

Effect of chitosan on weight loss in overweight and obese individuals: a systematic review of randomized controlled trials.

Mhurchu CN, Dunshea-Mooij C, Bennett D, Rodgers A.

Source
Clinical Trials Research Unit, University of Auckland, Auckland, New Zealand. [email protected]

Abstract

This article aims to determine whether chitosan, a popular, over-the-counter, weight loss supplement, is an effective treatment for overweight and obesity. It is designed as a systematic review of randomized controlled trials. The data sources include the electronic databases Medline, EMBASE, Biosis, CINAHL and Cochrane Central Register of Controlled Trials (CCTR); the specialized websites Controlled Trials, International Bibliographic Information on Dietary Supplements (IBIDS), System for Information on Grey Literature in Europe (SIGLE), Reuter's Health Service, Natural Alternatives International and Pharmanutrients; and bibliographies of relevant journal articles. Included were randomized controlled trials of chitosan with a minimum duration of 4 weeks in adults who were overweight or obese and/or had hypercholesterolaemia at baseline. Fourteen trials involving a total of 1071 participants were included in the review. Analyses involving all trials indicated that chitosan preparations result in a small but statistically significant greater reduction in body weight (weighted mean difference -1.7 kg; 95% confidence interval -2.1, -1.3 kg, P < 0.00001) compared with placebo. Analyses restricted to high-quality studies showed that reductions in weight [-0.6 (-1.2, 0.1) kg, P = 0.11] were less than in lower quality studies [-2.3 (-2.7, -1.8) kg, P < 0.00001]. Results obtained from high-quality trials indicate that the effect of chitosan on body weight is minimal and unlikely to be of clinical significance.

[rafael.orleaes]

Um estudo científico comprovou que a quitosana só emagrece quando sua toma é aliada a uma dieta hipocalórica. E mesmo assim, sua eficácia não é garantida, visto que não foi encontrada uma quantidade considerável de gordura nas fezes de todos os participantes, como era suposto.

A quitosa é feita a partir de esqueletos de frutos do mar, sendo por isso uma fibra natural, que auxilia no trânsito intestinal, e supostamente diminui a absorção de gorduras no intestino por aderir-se às moléculas de gordura ingeridas, impedindo que ela seja depositada no corpo.

Outro estudo revelou que a quitosana pode ajudar a emagrecer, mas que possui pouca eficácia. E ela estaria dependente da qualidade do produto e da alimentação do indivíduo.

A quitosana é um dos remédios para emagrecer mais utilizados no Brasil e nos Estados Unidos, mas crê-se que isso deve-se ao fato de ser um produto que pode ser comprado sem receita médica, e não pela sua eficácia.

Referências BIbliográficas

1. MHURCHU CN; PROPPITT SD; McGILL AT et al. The effect of the dietary supplement, Chitosan, on body weight:a randomised controlled trial in 250 overweight and obese adults. Acesso em Jan. 2012.
2. TOLEDO OR; CASTRO JAM; HONORIO-FRANÇA AC; FRANÇA EL; FERRARI CKB. Uso de medicamentos para perda de peso e índice de massa corporal em universitários do Vale do Araguaia (MT/GO), Amazônia Legal.

[Visitante usuario_excluido22s]

Concordo contudo.

Mas "significância clínica" para a obesidade é bem complicado de comparar com significância estética para usuários recreativos.

Eu mesmo já usei quitosana, e ainda uso nos cuttings, e os resultados são sempre excelentes.

[rafael.orleaes]

Cara eu ainda acho que o tal do óleo de cartámo é que funciona..

[mpcosta82]

Concordo contudo.

Mas "significância clínica" para a obesidade é bem complicado de comparar com significância estética para usuários recreativos.

Eu mesmo já usei quitosana, e ainda uso nos cuttings, e os resultados são sempre excelentes.

Hmm por que você postou como referência um estudo feito com pessoas com sobrepeso, então?

OK, sobrepeso não é obesidade, mas também não são usuários recreativos.

Não duvido que quitosana funcione, mas o efeito é pequeno; o único efeito dela é diminuir a absorção de gorduras no trato gastrointestinal - mas para isso você precisa ingerir ela junto de refeições ricas em gordura. Ainda assim o efeito é pequeno.

Talvez se os estudos tivessem feito justamente isso, analisado o efeito da quitosana durante refeições, os resultados fossem um pouco melhores.

É bem provável que os seus resultados tenham sido principalmente por causa do déficit calórico da sua dieta, e menos por causa da quitosana.

abraços

Cara eu ainda acho que o tal do óleo de cartámo é que funciona..

Tá de sacanagem, né? hehehe

aqui se vende óleo de cártamo porque a Anvisa não permite vender CLA, ácido conjugado linoléico. O CLA, por sua vez, só funciona com eficácia em ratos. Em humanos o efeito é mínimo.

O óleo de cártamo é usado para produzir sinteticamente CLA, mas ele em si não possui nada de CLA.

Óleo de cártamo nada mais é do que uma gordura poliinsaturada (com um pouco de saturada e monoinsaturada) - a mesma que você encontra em outros óleos vegetais. O efeito dele é zero para perda de gordura.

abraços

Editado Abril 9, 2013 às 20:56 por mpcosta82

[johntraceur]

Quero usar pois tenho uma disposiçao muito grande para ganhar peso, comecei a ir à academia recentemente e quero focar a perda de peso porem nao posso ir a academia todos os dias, posso ir 3x na semana e nos dias que nao posso ir posso fazer uma caminhada/corrida no parque municipal aqui em BH ,tenho o OxyElite em casa e gostaria de potencializar com algo que nao fizesse mal tomar, me indicaram a quitosana, muito obrigado pelas dicas