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Anybody here take CLA? Clinical studies reveal that:
*CLA is a significant anti-oxidant, which helps fight free radical damage.
*CLA increases energy and may suppress appetite.
*CLA has been shown to improve insulin sensitivity.
*CLA has beeen shown to be an anti-inflammatory.
*CLA reduces the production of cytokines.
*CLA reduces abdominal fat and preserves muscle mass.
I get mine from beef and eggs, etc.
[QUOTE=desslok;603640283]I get mine from beef and eggs, etc.[/QUOTE]
Our cattle are deficient in CLA and it would take a lot of beef to get enough and eggs have vitually no CLA unless you eat those that are produced from hens fed 5% CLA isomers.
[QUOTE=ClevageGobbler;603630563]Anybody here take CLA? Clinical studies reveal that:
*CLA is a significant anti-oxidant, which helps fight free radical damage.
*CLA increases energy and may suppress appetite.
*CLA has been shown to improve insulin sensitivity.
*CLA has beeen shown to be an anti-inflammatory.
*CLA reduces the production of cytokines.
*CLA reduces abdominal fat and preserves muscle mass.[/QUOTE][i]When non-commercially vested entities review CLA, the conclusions are not favorable:[/i]
Conjugated linoleic acid intake in humans: a systematic review focusing on its effect on body composition, glucose, and lipid metabolism.
Salas-Salvad J, Marquez-Sandoval F, Bull M. Crit Rev Food Sci Nutr. 2006;46(6):479-88.
Studies performed on different species show that the consumption of conjugated linoleic acid (CLA) leads to a loss of fat and total body weight, reduces the plasma concentrations of total and LDL cholesterol, and has an antiinflammatory effect. This article reviews the clinical trials on human beings that evaluate how mixtures of CLA isomers administered as supplements or CLA-enriched products can affect total body weight, body composition, plasma lipid profile, glycemia, insulinemia, insulin sensitivity, lipid oxidation, and inflammation. [b]After analyzing the few studies published to date in reduced samples of healthy humans or patients with overweight, obesity, metabolic syndrome, or diabetes, we deduce that there is not enough evidence to show that conjugated linoleic acid has an effect on weight and body composition in humans. However, some of these studies have observed that the administration of various CLA isomers has adverse effects on lipid profile (it decreases HDL cholesterol concentration and increases Lp(a) circulating levels), glucose metabolism (glycemia, insulinemia or insulin sensitivity), lipid oxidation, inflammation, or endothelial function.[/b] Therefore, long-term randomized clinical trials, controlled with placebo, need to be made in large samples of patients to evaluate the efficacy and safety of CLA isomers before its indiscriminate use in human beings can be recommended.
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The effects of conjugated linoleic acid on human health-related outcomes.
Tricon S, Burdge GC, Williams CM, Calder PC, Yaqoob P. Proc Nutr Soc. 2005 May;64(2):171-82.
Hugh Sinclair Unit of Human Nutrition, School of Food Bioscienes, University of Reading, Whiteknights, UK. [email]S.Tricon@reading.ac.uk[/email]
Conjugated linoleic acid (CLA) is a collective term for a mixture of positional and geometric isomers of conjugated dienoic derivatives of linoleic acid. CLA has received considerable attention as a result of animal experiments that report anti-carcinogenic, anti-atherogenic and anti-diabetic properties, and modulation of body composition and immune function. Several studies of CLA supplementation in human subjects have now been published, but in contrast to animal studies there has been marked variation between reports on the health-related outcomes. [b]The consensus from seventeen published studies in human subjects is that CLA does not affect body weight or body composition. Some detrimental effects of the trans-10,cis-12 CLA isomer have also been reported in terms of altered blood lipid composition and impaired insulin sensitivity.[/b] Finally, CLA has only limited effects on immune functions in man. However, there have been reports of some interesting isomer-specific effects of CLA on the blood lipid profile, but not on immune function. These isomer-specific effects need further investigation. Until more is known, CLA supplementation in man should be considered with caution.
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[i]The only CLA study done on resistance-trained subjects failed to show any effect:[/i]
Effects of conjugated linoleic acid supplementation during resistance training on body composition, bone density, strength, and selected hematological markers.
Kreider RB, Ferreira MP, Greenwood M, Wilson M, Almada AL. J Strength Cond Res. 2002 Aug;16(3):325-34.
Conjugated linoleic acids (CLA) are essential fatty acids that have been reported in animal studies to decrease catabolism, promote fat loss, increase bone density, enhance immunity, and serve as an antiatherogenic and anticarcinogenic agent. For this reason, CLA has been marketed as a supplement to promote weight loss and general health. CLA has also been heavily marketed to resistance-trained athletes as a supplement that may help lessen catabolism, decrease body fat, and promote greater gains in strength and muscle mass during training. Although basic research is promising, few studies have examined whether CLA supplementation during training enhances training adaptations and/or affects markers of health. This study evaluated whether CLA supplementation during resistance training affects body composition, strength, and/or general markers of catabolism and immunity. In a double-blind and randomized manner, 23 experienced, resistance-trained subjects were matched according to body mass and training volume and randomly assigned to supplement their diet with 9 g;pdd(-1) of an olive oil placebo or 6 g;pdd(-1) of CLA with 3 g;pdd(-1) of fatty acids for 28 days. Prior to and following supplementation, fasting blood samples, total body mass, and dual-energy X-ray absorptiometry (DEXA) determined body composition, and isotonic bench press and leg press 1 repetition maximums (1RMs) were determined. Results revealed that although some statistical trends were observed with moderate to large effect sizes, [b]CLA supplementation did not significantly affect (p > 0.05) changes in total body mass, fat-free mass, fat mass, percent body fat, bone mass, strength, serum substrates, or general markers of catabolism and immunity during training. These findings indicate that CLA does not appear to possess significant ergogenic value for experienced resistance-trained athletes.[/b]
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[i]CLA has adversely affected markers of cardiovascular health, without significantly affecting bodycomp:[/i]
Treatment with dietary trans10cis12 conjugated linoleic acid causes isomer-specific insulin resistance in obese men with the metabolic syndrome.
Diabetes Care. 2002 Sep;25(9):1516-21. Ris?rus U, Arner P, Brismar K, Vessby B.
OBJECTIVE: Conjugated linoleic acid (CLA) is a group of dietary fatty acids with antiobesity and antidiabetic effects in some animals. The trans10cis12 (t10c12) CLA isomer seems to cause these effects, including improved insulin sensitivity. Whether such isomer-specific effects occur in humans is unknown. The aim of this study was to investigate whether t10c12 CLA or a commercial CLA mixture could improve insulin sensitivity, lipid metabolism, or body composition in obese men with signs of the metabolic syndrome. RESEARCH DESIGN AND METHODS: In a randomized, double-blind controlled trial, abdominally obese men (n = 60) were treated with 3.4 g/day CLA (isomer mixture), purified t10c12 CLA, or placebo. Euglycemic-hyperinsulinemic clamp, serum hormones, lipids, and anthropometry were assessed before and after 12 weeks of treatment. RESULTS: Baseline metabolic status was similar between groups. [b]Unexpectedly, t10c12 CLA increased insulin resistance (19%; P < 0.01) and glycemia (4%; P < 0.001) and reduced HDL cholesterol [/b](-4%; P < 0.01) compared with placebo, whereas body fat, sagittal abdominal diameter, and weight decreased versus baseline, but the difference was not significantly different from placebo. The [b][color=blue]CLA mixture did not change glucose metabolism, body composition, or weight compared with placebo but lowered HDL cholesterol.[/color][/b](-2%; P < 0.05). CONCLUSIONS: These results reveal important isomer-specific metabolic actions of CLA in abdominally obese humans. A CLA-induced insulin resistance has previously been described only in lipodystrophic mice. Considering the use of CLA-supplements among obese individuals, it is important to clarify the clinical consequences of these results, but they also provide physiological insights into the role of specific dietary fatty acids as modulators of insulin resistance in humans.
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[i]More on CLA's adverse effects on cardiovascular health parameters, again, without improving bodycomp:[/i]
Effects of cis-9,trans-11 conjugated linoleic acid supplementation on insulin sensitivity, lipid peroxidation, and proinflammatory markers in obese men.
Am J Clin Nutr. 2004 Aug;80(2):279-83. Ris?rus U, Vessby B, Arnl?v J, Basu S.
[b]BACKGROUND: We recently showed that trans-10,cis-12 (t10,c12) conjugated linoleic acid (CLA) causes insulin resistance in obese men. [/b]However, metabolic effects of the c9,t11 CLA isomer are still unknown in obese men. [b]Because c9,t11 CLA is the predominant CLA isomer in foods and is included in dietary weight-loss products, it is important to conduct randomized controlled studies that use c9,t11 CLA preparations.[/b] OBJECTIVE: We investigated the effects of c9,t11 CLA supplementation on insulin sensitivity, body composition, and lipid peroxidation in a group at high risk for cardiovascular disease. DESIGN: In a randomized, double-blind, placebo-controlled study, 25 abdominally obese men received 3 g c9,t11 CLA/d or placebo (olive oil). Before and after 3 mo of supplementation, we assessed insulin sensitivity (hyperinsulinemic euglycemic clamp), lipid metabolism, body composition, and urinary 8-iso-prostaglandin F(2alpha) (a major F(2)-isoprostane) and 15-keto-dihydro-prostaglandin F(2alpha), markers of in vivo oxidative stress and inflammation, respectively. RESULTS: All subjects completed the study. Compared with placebo, c9,t11 CLA decreased insulin sensitivity by 15% (P < 0.05) and increased 8-iso-prostaglandin F(2alpha) and 15-keto-dihydro-prostaglandin F(2alpha) excretion by 50% (P < 0.01) and 15% (P < 0.05), respectively. The decreased insulin sensitivity was independent of changes in serum lipids, glycemia, body mass index, and body fat but was abolished after adjustment for changes in 8-iso-prostaglandin F(2alpha) concentrations. [b][color=blue]There were no differences between groups in body composition.[/color][/b] [b]CONCLUSIONS: A CLA preparation containing the purified c9,t11 CLA isomer increased insulin resistance and lipid peroxidation compared with placebo in obese men. Because c9,t11 CLA occurs in commercial supplements as well as in the diet, the present results should be confirmed in larger studies that also include women.[/b]
Conjugated linoleic acid isomers: differences in metabolism and biological effects.
Churruca I, Fernández-Quintela A, Portillo MP. Biofactors. 2009 Jan-Feb;35(1):105-11.
The term conjugated linoleic acid (CLA) refers to a mixture of linoleic acid positional and geometric isomers, characterized by having conjugated double bonds, not separated by a methylene group as in linoleic acid. CLA isomers appear as a minor component of the lipid fraction, found mainly in meat and dairy products from cows and sheep. The most abundant isomer is cis-9,trans-11, which represents up to 80% of total CLA in food. These isomers are metabolized in the body through different metabolic pathways, but important differences, that can have physiological consequences, are observed between the two main isomers. The trans-10,cis-12 isomer is more efficiently oxidized than the cis-9,trans-11 isomer, due to the position of its double bounds. Interest in CLA arose in its anticarcinogenic action but there is an increasing amount of specific scientific literature concerning the biological effects and properties of CLA. Numerous biological effects of CLA are due to the separate action of the most studied isomers, cis-9,trans-11 and trans-10,cis-12. It is also likely that some effects are induced and/or enhanced by these isomers acting synergistically. Although the cis-9,trans-11 isomer is mainly responsible for the anticarcinogenic effect, the trans-10,cis-12 isomer reduces body fat and it is referred as the most effective isomer affecting blood lipids. [b]As far as insulin function is concerned, both isomers seem to be responsible for insulin resistance in humans.[/b] Finally, with regard to the immune system it is not clear whether individual isomers of CLA could act similarly or differently.
------------------------------------------------------
Conjugated linoleic acid (CLA) and obesity.
Silveira MB, Carraro R, Monereo S, Tébar J. Public Health Nutr. 2007 Oct;10(10A):1181-6.
BACKGROUND: The term conjugated linoleic acid (CLA) refers to several positional and geometric conjugated dienoic isomers of linoleic acid (LA), of which the trans-10,cis-12 isomer has been reported to reduce adiposity and increase lean mass in mice and other animals when included at <or=1% of the diet. However, most dietary CLA in humans is obtained from dairy products, accounting for the cis-9,trans-11 CLA isomer, also known as rumenic acid, for more than 90% of the total CLA intake. Commercial CLA preparations industrially produced, containing trans-10,cis-12 and cis-9,trans-11 CLA isomers in diverse proportions, are attracting consumers' interest because of the purported body fat-lowering effects of CLA, coupled to the perception of a 'natural' compound devoid of harmful effects. Nevertheless, despite numerous studies on CLA effects on body composition for nearly a decade, the mechanisms by which CLA isomers elicit their effects remain largely unknown. The purpose of this paper is to provide an updated review of the studies performed on animals and humans, as well as to describe the potential mechanisms involved in CLA effects on body weight and composition and metabolism.
METHOD: Literature review.
[b]RESULTS: Experiments in humans have not been able to show a significant effect on body weight, body composition or weight regain related to either of the CLA isomers.[/b] In fact, some studies suggest a tendency towards a decrease in body fat mass and an increase in body lean mass, while some others raise concern about the possibility of deleterious effects of trans-10,cis-12 CLA on lipid profile, glucose metabolism and insulin sensitivity.
CONCLUSIONS: Evidence regarding effectiveness of CLA in humans is not concluding.
--------------------------------------------------------
Conjugated linoleic acid and human health: a critical evaluation of the evidence.
Tricon S, Yaqoob P. Curr Opin Clin Nutr Metab Care. 2006 Mar;9(2):105-10.
PURPOSE OF REVIEW: This review critically evaluates studies investigating the effects of conjugated linoleic acid on human health, including effects on body composition, blood lipids, liver metabolism, insulin sensitivity and immune function. It focuses mainly on human intervention studies, but includes some reference to animal and cellular studies which provide insight into potential molecular mechanisms of action of conjugated linoleic acid.
RECENT FINDINGS: Human studies continue to report inconsistent effects of conjugated linoleic acid on human health. Some of these reports are based on overinterpretation of marginal effects of supplementation. Recent data suggest that the effects of the substance may be isomer dependent and that cis-9,trans-11 and trans-10,cis-12 conjugated linoleic acids have opposing effects on blood lipids and on metabolism in adipocytes and hepatic cells.
[b]SUMMARY: Claims that conjugated linoleic acid is beneficial for health remain as yet unconvincing. [/b]Human studies investigating the effects of conjugated linoleic acid supplements have tended to use mixtures of isomers and have been inconsistent. More recent studies have attempted to use relatively pure preparations of single isomers and these studies suggest that the effects of conjugated linoleic acid may be isomer-specific. These recent data suggest a relative detrimental effect of trans-10,cis-12 conjugated linoleic acid on blood lipids. There appears to be little effect of conjugated linoleic acid on immune function and the effects on insulin sensitivity remain unclear.
---------------------------------------------------------
Conjugated linoleic acid: a functional nutrient in the different pathophysiological components of the metabolic syndrome?
Toomey S, McMonagle J, Roche HM. Curr Opin Clin Nutr Metab Care. 2006 Nov;9(6):740-7.
PURPOSE OF REVIEW: Much attention has focused on the therapeutic potential of conjugated linoleic acid with the most abundant isomers being cis-9,trans-11 conjugated linoleic acid and trans-10,cis-12 conjugated linoleic acid. Initial animal studies associated conjugated linoleic acid with beneficial health properties, such as reducing the risk of cancer, diabetes, atherosclerosis, inflammation and obesity. This review has appraised the evidence in relation to the effect of conjugated linoleic acid on components of the metabolic syndrome (clinically or experimentally), in particular, obesity, insulin resistance, atherosclerosis and inflammation.
[b]RECENT FINDINGS: More recent human conjugated linoleic acid supplementation studies have often shown conflicting and less convincing health benefits. [/b]The marked variation between studies may reflect the isomer-specific effect of the individual conjugated linoleic acid isomers, which can often have opposing effects. Detrimental effects have been observed in some studies, in particular after supplementation with the trans-10,cis-12 conjugated linoleic acid isomer.
SUMMARY: Further studies and long-term clinical trials will be required to determine the efficacy and safety of conjugated linoleic acid isomers before conjugated linoleic acid could be considered as a functional nutrient in humans.
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[b][color=red]OVERALL MESSAGE:[/b][/color] Save your money, broski.
[QUOTE=alan aragon;603673473]Conjugated linoleic acid isomers: differences in metabolism and biological effects.
Churruca I, Fernández-Quintela A, Portillo MP. Biofactors. 2009 Jan-Feb;35(1):105-11.
The term conjugated linoleic acid (CLA) refers to a mixture of linoleic acid positional and geometric isomers, characterized by having conjugated double bonds, not separated by a methylene group as in linoleic acid. CLA isomers appear as a minor component of the lipid fraction, found mainly in meat and dairy products from cows and sheep. The most abundant isomer is cis-9,trans-11, which represents up to 80% of total CLA in food. These isomers are metabolized in the body through different metabolic pathways, but important differences, that can have physiological consequences, are observed between the two main isomers. The trans-10,cis-12 isomer is more efficiently oxidized than the cis-9,trans-11 isomer, due to the position of its double bounds. Interest in CLA arose in its anticarcinogenic action but there is an increasing amount of specific scientific literature concerning the biological effects and properties of CLA. Numerous biological effects of CLA are due to the separate action of the most studied isomers, cis-9,trans-11 and trans-10,cis-12. It is also likely that some effects are induced and/or enhanced by these isomers acting synergistically. Although the cis-9,trans-11 isomer is mainly responsible for the anticarcinogenic effect, the trans-10,cis-12 isomer reduces body fat and it is referred as the most effective isomer affecting blood lipids. [b]As far as insulin function is concerned, both isomers seem to be responsible for insulin resistance in humans.[/b] Finally, with regard to the immune system it is not clear whether individual isomers of CLA could act similarly or differently.
------------------------------------------------------
Conjugated linoleic acid (CLA) and obesity.
Silveira MB, Carraro R, Monereo S, Tébar J. Public Health Nutr. 2007 Oct;10(10A):1181-6.
BACKGROUND: The term conjugated linoleic acid (CLA) refers to several positional and geometric conjugated dienoic isomers of linoleic acid (LA), of which the trans-10,cis-12 isomer has been reported to reduce adiposity and increase lean mass in mice and other animals when included at <or=1% of the diet. However, most dietary CLA in humans is obtained from dairy products, accounting for the cis-9,trans-11 CLA isomer, also known as rumenic acid, for more than 90% of the total CLA intake. Commercial CLA preparations industrially produced, containing trans-10,cis-12 and cis-9,trans-11 CLA isomers in diverse proportions, are attracting consumers' interest because of the purported body fat-lowering effects of CLA, coupled to the perception of a 'natural' compound devoid of harmful effects. Nevertheless, despite numerous studies on CLA effects on body composition for nearly a decade, the mechanisms by which CLA isomers elicit their effects remain largely unknown. The purpose of this paper is to provide an updated review of the studies performed on animals and humans, as well as to describe the potential mechanisms involved in CLA effects on body weight and composition and metabolism.
METHOD: Literature review.
[b]RESULTS: Experiments in humans have not been able to show a significant effect on body weight, body composition or weight regain related to either of the CLA isomers.[/b] In fact, some studies suggest a tendency towards a decrease in body fat mass and an increase in body lean mass, while some others raise concern about the possibility of deleterious effects of trans-10,cis-12 CLA on lipid profile, glucose metabolism and insulin sensitivity.
CONCLUSIONS: Evidence regarding effectiveness of CLA in humans is not concluding.
--------------------------------------------------------
Conjugated linoleic acid and human health: a critical evaluation of the evidence.
Tricon S, Yaqoob P. Curr Opin Clin Nutr Metab Care. 2006 Mar;9(2):105-10.
PURPOSE OF REVIEW: This review critically evaluates studies investigating the effects of conjugated linoleic acid on human health, including effects on body composition, blood lipids, liver metabolism, insulin sensitivity and immune function. It focuses mainly on human intervention studies, but includes some reference to animal and cellular studies which provide insight into potential molecular mechanisms of action of conjugated linoleic acid.
RECENT FINDINGS: Human studies continue to report inconsistent effects of conjugated linoleic acid on human health. Some of these reports are based on overinterpretation of marginal effects of supplementation. Recent data suggest that the effects of the substance may be isomer dependent and that cis-9,trans-11 and trans-10,cis-12 conjugated linoleic acids have opposing effects on blood lipids and on metabolism in adipocytes and hepatic cells.
[b]SUMMARY: Claims that conjugated linoleic acid is beneficial for health remain as yet unconvincing. [/b]Human studies investigating the effects of conjugated linoleic acid supplements have tended to use mixtures of isomers and have been inconsistent. More recent studies have attempted to use relatively pure preparations of single isomers and these studies suggest that the effects of conjugated linoleic acid may be isomer-specific. These recent data suggest a relative detrimental effect of trans-10,cis-12 conjugated linoleic acid on blood lipids. There appears to be little effect of conjugated linoleic acid on immune function and the effects on insulin sensitivity remain unclear.
---------------------------------------------------------
Conjugated linoleic acid: a functional nutrient in the different pathophysiological components of the metabolic syndrome?
Toomey S, McMonagle J, Roche HM. Curr Opin Clin Nutr Metab Care. 2006 Nov;9(6):740-7.
PURPOSE OF REVIEW: Much attention has focused on the therapeutic potential of conjugated linoleic acid with the most abundant isomers being cis-9,trans-11 conjugated linoleic acid and trans-10,cis-12 conjugated linoleic acid. Initial animal studies associated conjugated linoleic acid with beneficial health properties, such as reducing the risk of cancer, diabetes, atherosclerosis, inflammation and obesity. This review has appraised the evidence in relation to the effect of conjugated linoleic acid on components of the metabolic syndrome (clinically or experimentally), in particular, obesity, insulin resistance, atherosclerosis and inflammation.
[b]RECENT FINDINGS: More recent human conjugated linoleic acid supplementation studies have often shown conflicting and less convincing health benefits. [/b]The marked variation between studies may reflect the isomer-specific effect of the individual conjugated linoleic acid isomers, which can often have opposing effects. Detrimental effects have been observed in some studies, in particular after supplementation with the trans-10,cis-12 conjugated linoleic acid isomer.
SUMMARY: Further studies and long-term clinical trials will be required to determine the efficacy and safety of conjugated linoleic acid isomers before conjugated linoleic acid could be considered as a functional nutrient in humans.
------------------------------------------------------------------
[b][color=red]OVERALL MESSAGE:[/b][/color] Save your money, broski.[/QUOTE]
Yeeuh, thanks.
[QUOTE=alan aragon;603673473]Conjugated linoleic acid isomers: differences in metabolism and biological effects.
Churruca I, Fernández-Quintela A, Portillo MP. Biofactors. 2009 Jan-Feb;35(1):105-11.
The term conjugated linoleic acid (CLA) refers to a mixture of linoleic acid positional and geometric isomers, characterized by having conjugated double bonds, not separated by a methylene group as in linoleic acid. CLA isomers appear as a minor component of the lipid fraction, found mainly in meat and dairy products from cows and sheep. The most abundant isomer is cis-9,trans-11, which represents up to 80% of total CLA in food. These isomers are metabolized in the body through different metabolic pathways, but important differences, that can have physiological consequences, are observed between the two main isomers. The trans-10,cis-12 isomer is more efficiently oxidized than the cis-9,trans-11 isomer, due to the position of its double bounds. Interest in CLA arose in its anticarcinogenic action but there is an increasing amount of specific scientific literature concerning the biological effects and properties of CLA. Numerous biological effects of CLA are due to the separate action of the most studied isomers, cis-9,trans-11 and trans-10,cis-12. It is also likely that some effects are induced and/or enhanced by these isomers acting synergistically. Although the cis-9,trans-11 isomer is mainly responsible for the anticarcinogenic effect, the trans-10,cis-12 isomer reduces body fat and it is referred as the most effective isomer affecting blood lipids. [b]As far as insulin function is concerned, both isomers seem to be responsible for insulin resistance in humans.[/b] Finally, with regard to the immune system it is not clear whether individual isomers of CLA could act similarly or differently.
------------------------------------------------------
Conjugated linoleic acid (CLA) and obesity.
Silveira MB, Carraro R, Monereo S, Tébar J. Public Health Nutr. 2007 Oct;10(10A):1181-6.
BACKGROUND: The term conjugated linoleic acid (CLA) refers to several positional and geometric conjugated dienoic isomers of linoleic acid (LA), of which the trans-10,cis-12 isomer has been reported to reduce adiposity and increase lean mass in mice and other animals when included at <or=1% of the diet. However, most dietary CLA in humans is obtained from dairy products, accounting for the cis-9,trans-11 CLA isomer, also known as rumenic acid, for more than 90% of the total CLA intake. Commercial CLA preparations industrially produced, containing trans-10,cis-12 and cis-9,trans-11 CLA isomers in diverse proportions, are attracting consumers' interest because of the purported body fat-lowering effects of CLA, coupled to the perception of a 'natural' compound devoid of harmful effects. Nevertheless, despite numerous studies on CLA effects on body composition for nearly a decade, the mechanisms by which CLA isomers elicit their effects remain largely unknown. The purpose of this paper is to provide an updated review of the studies performed on animals and humans, as well as to describe the potential mechanisms involved in CLA effects on body weight and composition and metabolism.
METHOD: Literature review.
[b]RESULTS: Experiments in humans have not been able to show a significant effect on body weight, body composition or weight regain related to either of the CLA isomers.[/b] In fact, some studies suggest a tendency towards a decrease in body fat mass and an increase in body lean mass, while some others raise concern about the possibility of deleterious effects of trans-10,cis-12 CLA on lipid profile, glucose metabolism and insulin sensitivity.
CONCLUSIONS: Evidence regarding effectiveness of CLA in humans is not concluding.
--------------------------------------------------------
Conjugated linoleic acid and human health: a critical evaluation of the evidence.
Tricon S, Yaqoob P. Curr Opin Clin Nutr Metab Care. 2006 Mar;9(2):105-10.
PURPOSE OF REVIEW: This review critically evaluates studies investigating the effects of conjugated linoleic acid on human health, including effects on body composition, blood lipids, liver metabolism, insulin sensitivity and immune function. It focuses mainly on human intervention studies, but includes some reference to animal and cellular studies which provide insight into potential molecular mechanisms of action of conjugated linoleic acid.
RECENT FINDINGS: Human studies continue to report inconsistent effects of conjugated linoleic acid on human health. Some of these reports are based on overinterpretation of marginal effects of supplementation. Recent data suggest that the effects of the substance may be isomer dependent and that cis-9,trans-11 and trans-10,cis-12 conjugated linoleic acids have opposing effects on blood lipids and on metabolism in adipocytes and hepatic cells.
[b]SUMMARY: Claims that conjugated linoleic acid is beneficial for health remain as yet unconvincing. [/b]Human studies investigating the effects of conjugated linoleic acid supplements have tended to use mixtures of isomers and have been inconsistent. More recent studies have attempted to use relatively pure preparations of single isomers and these studies suggest that the effects of conjugated linoleic acid may be isomer-specific. These recent data suggest a relative detrimental effect of trans-10,cis-12 conjugated linoleic acid on blood lipids. There appears to be little effect of conjugated linoleic acid on immune function and the effects on insulin sensitivity remain unclear.
---------------------------------------------------------
Conjugated linoleic acid: a functional nutrient in the different pathophysiological components of the metabolic syndrome?
Toomey S, McMonagle J, Roche HM. Curr Opin Clin Nutr Metab Care. 2006 Nov;9(6):740-7.
PURPOSE OF REVIEW: Much attention has focused on the therapeutic potential of conjugated linoleic acid with the most abundant isomers being cis-9,trans-11 conjugated linoleic acid and trans-10,cis-12 conjugated linoleic acid. Initial animal studies associated conjugated linoleic acid with beneficial health properties, such as reducing the risk of cancer, diabetes, atherosclerosis, inflammation and obesity. This review has appraised the evidence in relation to the effect of conjugated linoleic acid on components of the metabolic syndrome (clinically or experimentally), in particular, obesity, insulin resistance, atherosclerosis and inflammation.
[b]RECENT FINDINGS: More recent human conjugated linoleic acid supplementation studies have often shown conflicting and less convincing health benefits. [/b]The marked variation between studies may reflect the isomer-specific effect of the individual conjugated linoleic acid isomers, which can often have opposing effects. Detrimental effects have been observed in some studies, in particular after supplementation with the trans-10,cis-12 conjugated linoleic acid isomer.
SUMMARY: Further studies and long-term clinical trials will be required to determine the efficacy and safety of conjugated linoleic acid isomers before conjugated linoleic acid could be considered as a functional nutrient in humans.
------------------------------------------------------------------
[b][color=red]OVERALL MESSAGE:[/b][/color] Save your money, broski.[/QUOTE]
thanks man
I was just looking for some Scientific research on the benefits of CLA in terms of is it a good supplementation for lean gains, body fat reduction, muscle mass... etc - and found all this!! ^^^
Thanks to Alan Aragon I got everything I need. Overall message: CLA = just another over-hyped bull**** supplement to lose BANK not BODY FAT :)
This is one of the very few studies ive seen that shows no positive effects of cla. The majority of studies i have read conclude that cla will indeed promote slight fat loss. There was actually a study i read saying it will improve insulin sensitivity rather than worsen it. To see for yourself just google "Cla fat ncbi"