- The Fat-Reducing Effects of Conjugated Linoleic Acid
As you have been reading, it is virtually impossible to achieve a sustained reduction in body fat without hormone modulation. If postprandial insulin is high, it must be suppressed. If thyroid hormone status is low, it must be brought back to normal. Estrogen, testosterone, and DHEA should be restored to youthful ranges.
In addition to correcting a hormone imbalance that may be the underlying cause of unwanted weight gain, certain dietary supplements can help facilitate and sustain fat loss. These low-cost supplements should be used in addition to physician-supervised hormone modulation therapy.The Fat-Reducing Effects of Conjugated Linoleic Acid
Conjugated linoleic acid (CLA) is a fatty acid component of beef and milk that has been shown to reduce body fat in both animals and humans. CLA is essential for the transport of dietary fat into cells, where it is used to build muscle and produce energy. Fat that is not used for anabolic energy production is converted into newly stored fat cells.
The primary dietary sources of CLA are beef and milk, but Americans are eating less beef and drinking less whole milk in order to reduce their dietary intake of saturated fat. People often drink nonfat milk, but it is the fat content of milk that contains CLA. Because skim milk contains virtually no CLA, persons seeking to lose weight who also drink skim milk are depriving themselves of a potential source of this fat-reducing nutrient.
In 1963, the CLA percentage in milk was as high as 2.81%. By 1992, the percentage of CLA in dairy products seldom exceeded 1%. The reason for the sharp reduction in milk CLA was because of changing feeding patterns. Cows that eat natural grass produce large amounts of CLA. Today's "efficient" feeding methods rely on far less natural grass. For example, grass-fed Australian cows have three to four times as much CLA in their meat as do American cows.
However, health-conscious Americans avoid beef and whole milk because these foods are high in fat, and when people do consume beef or milk, they are consuming very little CLA because of the deficiency of CLA in cows today. Thus, most Americans have inadequate amounts of CLA in their diet. This CLA deficiency might be at least partially responsible for the epidemic of overweight people of all ages that now exists.HOW BODY FAT ACCUMULATES
- CLA Fat-Loss Studies
- Preventing Cancer While Losing Weight
- How CLA Induces Fat Loss
- The Safety of CLA
Excess body fat accumulates via two distinct mechanisms. People either form more adipocytes (fat cells) and/or existing adipocytes absorb too much fat and become larger. The effect of too many adipocytes and/or "bloated" adipocytes is the unsightly and unhealthy amassing of body fat.
Conjugated linoleic acid (CLA) has been shown to decrease the volume of adipocytes and thus reduce body fat (Park et al. 1997, 1999). However, many overweight people have too many adipocytes (fat cells). These people need more than CLA to achieve effective weight control.
At the Experimental Biology 2002 meeting (New Orleans, Louisiana, April 19-24, 2002), scientists presented a fascinating study in which a group of mice was supplemented with CLA or CLA plus guarana. After 6 weeks, both groups of mice showed a substantial reduction in fat mass. In the CLA-only group, the decrease in fat mass was due to dramatic reduction in adipocyte size without a change in adipocyte number. In the CLA plus guarana group, both adipocyte size and number were reduced by 50% (FASEB 2002). The results of this study demonstrate that dietary CLA decreases excess fat accumulation by reducing the capacity of adipocytes to store fat. When guarana is added to CLA, there is an additional effect of reduction in adipocyte number and a decrease in adipocyte size. The impact of this finding in preventing obesity is profound.CLA Fat-Loss Studies
In July 1996; The Life Extension Foundation introduced CLA to its members. At the time of launch, numerous published studies had already detailed this nutrient's anti-cancer effects. What had impressed scientists was the fact that only relatively small amounts of CLA (3-4 grams per day) were required to achieve all of its wonderful effects.
In weight-loss studies, CLA consistently shows an ability to reduce body fat while maintaining lean muscle mass. In one study, mice fed the human equivalent of 3000-4000 mg a day of CLA achieved a 60% reduction in body fat and a 14% increase of lean body mass (Terpstra et al. 2002). Another study conducted at Louisiana State University reported up to an 88% reduction in the body fat of male mice fed CLA--after only 6 weeks (West et al. 1998).
A particularly significant study entitled "Dietary Conjugated Linoleic Acids Increase Lean Tissue and Decrease Fat Deposition in Growing Pigs" was reported in the November 1999 issue of The Journal of Nutrition (Ostrowska et al. 1999). The key element of the study was confirmation that CLA is able to decrease fat storage and maintain lean muscle tissue. In this study, researchers used young female pigs to illustrate the effects of combining a relatively small amount of CLA with the normal diet of the pigs. Because pigs have organs and metabolism similar to humans, they are good experimental models of human nutrition. Sixty pigs were randomly placed in one of six dietary treatments; one was the control group that received no CLA. Each other group received one of five different concentrations of CLA added to the feed. The pigs had free access to water and their diet at all times (2 kilograms of food per day).
After only 4 weeks of CLA supplementation, there was significantly less fat and leaner tissue in the groups receiving the CLA. After 8 weeks, the pigs with the highest CLA supplementation showed a 31% loss of body fat and a 5% increase in lean tissue. In addition, at the highest level of CLA supplementation, the back fat depth was reduced by 25%. This study was the first to show the profound effects of CLA supplements on the composition and deposition of body fat, in relation to protein, water, and other tissues of pigs (Ostrowska et al. 1999).
A study in The International Journal of Obesity concluded that CLA reduced abdominal fat among men classified as abdominally obese (Riserus et al. 2001). The study participants taking CLA lost an average of 1.4 cm in waist circumference after only 4 weeks. This double-blind, randomized, placebo-controlled trial observed 25 men with significant abdominal fat for 4 weeks: 14 received 4.2 grams of CLA per day, while the others received placebo. At the conclusion of the study, there was a significant decrease of abdominal diameter in the CLA group. None of the study participants changed their eating or exercise habits during the trial period (Riserus et al. 2001).
Results of the Riserus et al. (2001) study supported data published in the December 2000 issue of The Journal of Nutrition. That study concluded that CLA reduced body fat and preserved muscle mass among the 60-person study group. Participants lost an average of 6 pounds while taking CLA (Blankson et al. 2000).
CLA is a unique supplement because not only does it guard against serious diseases, but it is also an effective tool for one of the most serious conditions affecting Americans--obesity. As more and more Americans join the ranks of the overweight, millions more start diets that are usually destined to fail.Preventing Cancer While Losing Weight
CLA is not just for fat loss. Studies show CLA may also help protect against many diseases including atherosclerosis and cancer.
In an article appearing in The Journal of Nutrition, significant cancer-preventing properties were shown when CLA was added to the diet (Ip et al. 1999a). The study revealed that CLA was a "potent cancer preventative agent in animal models." Specifically, it was determined that feeding CLA to female rats while they were young and still developing conferred life-long protection from breast cancer. This preventive action was achieved by adding only enough CLA to equal 0.8% of the animal's total diet. This compares favorably with Life Extension's recommendation of 3000-4000 mg daily, which is approximately 1% of an average human's diet (Ip et al. 1999a).
In an earlier study in Experimental Cell Research, CLA was shown to prevent mammary cancer in rats if given before the onset of puberty (Ip et al. 1999b). Even more important, if CLA was ingested during the time of the "promotion" phase of cancer development, the rats were conferred substantial protection from further developing breast cancer. Another significant finding was that CLA appeared to actually inhibit the growth of normal mammary epithelial cell organoids and induced apoptosis or cell death in some of those same cells. The researchers concluded that this led to a reduction in the density of the developing mammary glands in rats and, therefore, the incidence of breast cancer was reduced (Ip et al. 1999b).
In the June 1999 issue of the journal Carcinogenesis, CLA was shown to reduce the size of breast tissue in the rat and thereby reduce the incidence of carcinogenesis (Banni et al. 1999). In another study reported in Anticancer Research, it was shown that CLA is also able to inhibit the growth of prostate cancer (Cesano et al. 1998). As reported in the article, CLA can be considered to be a powerful prostate cancer preventive as well as a partial treatment.
CLA may work via a similar mechanism to anti-diabetic drugs such as Avandia and Actos to not only enhance insulin sensitivity, but to also protect against cancer. A report in the journal Medical Hypothesis pointed out that a number of human cancer cell lines express the PPAR-gamma transcription factor, and agonists for PPAR-gamma can promote apoptosis in these cell lines and impede their clonal expansion both in vitro and in vivo. CLA can activate PPAR-gamma in rat adipocytes, possibly explaining the anti-diabetic effects of CLA in Zucker fatty rats. The report concluded by stating: "It is thus reasonable to suspect that a portion of CLA's broad spectrum anticarcinogenic activity is mediated by PPAR-gamma activation in susceptible tumors" (McCarty 2000).Note: The term "PPAR-gamma" is an acronym for "peroxisome proliferator activator-receptors-gamma." A PPAR-gamma agonist such as Avandia, Actos, or CLA activates the PPAR-gamma receptor. This class of drug is being investigated as a potential adjuvant therapy against certain types of cancer.
Another finding that provides insight into the biochemical action of CLA is its ability to suppress arachidonic acid. Since arachidonic acid can produce inflammatory compounds that can aid cancer proliferation, this may be yet another explanation for the anticancer effects of CLA. The suggested amount required to obtain the overall cancer-preventing effects is only 3000-4000 mg a day.
Clearly, we can expect more research and more interest in this fascinating supplement that has already been proven to be a formidable foe against cancer and to be able to promote weight loss with the development of lean tissue.How CLA Induces Fat Loss
The May 2002 issue of The Journal of Nutrition described a study conducted to ascertain the effects of CLA on calorie burning and fat storage in mice (Terpstra et al. 2002). CLA was shown to lower the amount of ingested food that was stored as body fat. CLA also increased the amount of fat excreted in the feces. Additionally, the study found that CLA induced a reduction in body fat mass on mice fed either a calorie-restricted or normal diet. The scientists defined the term "energy expenditure" as being the amount of food ingested minus the food retained in the body carcass and in the feces. CLA-fed mice showed a 74% increase in energy expenditure. The scientists thus concluded that the lower amount of ingested food stored on the body carcass was accounted for by this significant increase in energy expenditure (Terpstra et al. 2002).
This new finding corroborates a study conducted at Louisiana State University in which feeding male mice a CLA-enriched diet for 6 weeks resulted in 43%-88% lower body fat, especially in regard to abdominal fat. This occurred even if the mice were fed a high-fat diet. The effect was partly due to reduced calorie intake by CLA-supplemented mice and partly to a shift in their metabolism, including a higher metabolic rate (West et al. 1998).
In another study, performed at the University of Wisconsin-Madison, mice supplemented with only 0.5% of CLA showed up to 60% lower body fat and up to 14% increased lean body mass compared to controls. The researchers discovered that CLA-fed animals showed greater activity of enzymes involved in the delivery of fatty acids to the muscle cells and the utilization of fat for energy, while the enzymes facilitating fat deposition were inhibited (Terpstra et al. 2002).The Safety of CLA
In a study conducted by the Nutrition Department of Kraft Foods, male rats were fed a diet of 1.5% CLA, which is 50 times higher than the estimated upper-range human intake. The animals were examined weekly for any signs of toxicity; no toxicity was found. After the end of the 36-week study, the animals were sacrificed and autopsied. Again, no abnormal pathology was found. The study confirmed that CLA supplementation is safe even at high doses. Nevertheless, high doses are not necessary for obtaining the benefits of CLA (Scimeca 1998).
A dose of three to four 1000-mg capsules of 76% CLA, taken in the morning or before lunch on an empty stomach, may be an effective part of an overall weight-loss program. Research studies indicate that it usually takes about 3 weeks before body fat loss occurs in response to CLA supplementation.HOW GUARANA INDUCES FAT LOSS
- Clinical Studies on Guarana
Guarana is an herb that contains a form of caffeine called guaranine which is 2.5 times stronger than the caffeine found in coffee, tea, and soft drinks. What makes guaranine unique from the caffeine found in beverages is its slower release. That is because the guarana seed is fatty (even in powder form) and is not readily water-soluble. Therefore, the body does not quickly absorb it.
Since guaranine is released slowly, over a period as long as 6 hours, the energy boost that is experienced from guarana is not like that of coffee (a sudden rush and quick drop-off). Rather, the energy boost continues to escalate over hours.
While caffeine from beverages provides a short-lived energy burst that overheats and excites the body, guaranine has a cooling action that revitalizes and relaxes. This is because guarana contains other components that modify the activity of guaranine. The end result is more beneficial to the body than tea or coffee.
Guarana aids in a temporary, natural increase in body temperature and metabolic thermogenesis through nutritional stimulation of the body's beta-receptor pathway, which can induce the breakdown and release of stored body fat and thereby allow stored fats to be turned into energy. Thermogenesis refers to the body's production of heat. Heat production is a normal part of metabolic processes and can be enhanced by certain nutritional substances. Thermogenesis is both a source of heat and, when stimulated through appropriate dietary supplementation, a mechanism to increase metabolic rate. Stored body fat, if released and available for use, can provide the fuel for this increased metabolic rate.
Other active constituents of guarana are theobromine and theophylline, which are called xanthines (a class of thermogenic substances found in coffee, tea, and certain beans). They have some effect on increasing metabolic rate, suppressing appetite, and enhancing both physical and mental performance. They also act as muscle relaxants and possess diuretic properties.
Interestingly, caffeine accelerates the effectiveness of CLA, thus making CLA a more potent fat burner. Guarana has been shown to stimulate the migration of lipids so fat can be burned as energy. It is also an appetite suppressant.
Guarana also increases mental alertness, fights fatigue, and increases stamina and physical endurance. Guarana is taken daily as a health tonic by millions of Brazilians. In the United States, guarana holds GRAS-status (Generally Regarded as Safe). In 1989 a patent was filed on a guarana seed extract that was capable of inhibiting platelet aggregation in mammals. The patent described guarana's ability to prevent the formation of blood clots and to help in the breakdown of clots that had already been formed. Clinical evidence was presented in conjunction with the patent in 1989 and again in 1991 by a Brazilian research group demonstrating these anti-aggregation properties (Bydlowski et al. 1991).Clinical Studies on Guarana
In a study reported in The Journal of Human Nutrition Diet, guarana extract induced weight loss for over 45 days in overweight patients taking a mixed herbal preparation containing yerbemate, guarana, and damiana (Andersen et al. 2001). Body weight reductions were 11.22 pounds in the guarana group compared to less than 1 pound in the group receiving placebo for 45 days.
Guarana extract and its fractions decreased platelet aggregation up to 37% of control values and decreased platelet thromboxane formation from arachidonic acid up to 78% of control values (Bydlowski et al. 1991). When platelets hyperaggregate and/or when excess thromboxane formation occurs, this can initiate an arterial blood clot, which results in a heart attack or ischemic stroke.
In a 1997 study in rats, guarana increased the physical activity of the rats as well as increased physical endurance under stress and increased memory with single doses as well as with chronic doses. Interestingly enough, this study revealed that whole guarana seed extract performed better and more effectively than a comparable dosage of caffeine or ginseng extract (Espinola et al. 1997).
Another Brazilian research group has studied the apparent effect of guarana to increase memory, which is thought to be linked to the essential oils found in the seed (Galduroz et al. 1996). Its antibacterial properties against Escherichia coli and Salmonella have been documented as well (da Fonseca et al. 1994).
A 1998 toxicology study with animals has shown that guarana is nontoxic at even high dosages of up to 2 grams/kg of body weight. This same study demonstrated the antioxidant properties of guarana, saying: "Guarana showed an antioxidant effect because, even at low concentrations (1.2 mcg/mL), it inhibited the process of lipid peroxidation" (Mattei et al. 1998).
A major advantage to taking guarana in an oil base capsule is its relatively slow release into the body. In a study reported in the journal Pharmacology Biochemical Behavior in November 1997, a comparison was made of the absorption of caffeine from coffee, cola, or capsules. Based on saliva caffeine concentrations, the absorption from capsules was about 40% slower than that of coffee or colas. These capsules were not oil-based, yet the rate of caffeine absorption was still significantly slower than coffee or cola (Liguori et al. 1997).CLA + GUARANA
The effect of CLA on blocking excess absorption of serum glucose and fatty acids into adipocytes (fat cells) is remarkable. CLA induces a reduction in the size of adipocytes. One of the reasons that people gain weight as they age is that their adipocytes literally become fatter.
Another cause of increased body fat storage is the proliferation of adipocytes. Whereas CLA helps block the absorption of fat and sugar into adipocytes, CLA does not reduce the actual number of adipocytes present. Guarana has been shown to specifically reduce the number of adipocytes. When CLA was combined with guarana, there was a 50% reduction in adipocyte number (FASEB 2002).
In response to the FASEB (2002) study showing an added benefit when CLA is combined with guarana, a supplement has been formulated that contains potencies of CLA and guarana that have demonstrated fat-loss effects in published studies (available from Life Extension Foundation). CLA is also available by itself as a supplement for those who are overly sensitive to caffeine.
Whereas many published studies document the fat-reducing effects of CLA, the fact that CLA may protect against cancer, vascular disease, and Type II diabetes makes it a preferred supplement for health-conscious people to use daily.THE "FRIENDLY" FATS
There are fats that are healthy and fats that are dangerous. Hydrogenated fats are made by bubbling hydrogen gas with nickel as a catalyst to make the oil more solid at room temperature. This is how margarine and Crisco? are made. During the process, many of the chemical bonds are broken and reformed into less healthy trans configurations.
Healthy fats have a distinct flavor and unfortunately tend to become rancid after a few weeks, even with refrigeration. The healthiest oils are cold-pressed to avoid the chemical changes that occur during heating. Healthy oils are made from olives, flax seed, borage seeds, and even hemp. Each has its own unique flavor.
Not long ago, low-fat diet gurus were trying to terrorize people into further reducing all fat consumption. Now that we have witnessed the epidemic of obesity that followed, we know better. Healthy fats help keep us slender! They also help protect against atherosclerosis, cancer, diabetes, autoimmune diseases, and various other degenerative disorders.
Through their impact on important metabolic enzymes, healthy fats increase the synthesis of beneficial prostaglandins E1 and E3 while decreasing the levels of inflammatory prostaglandin E2; they also modify cell membrane composition and fluidity. Hence, improved blood flow and tissue oxygenation, higher metabolic rate, improved insulin sensitivity, immune enhancement, more muscle and bone formation, better brain function, and faster nerve impulse conductance result, to mention just a few of the major benefits.
Thus, while in the 1970s and 1980s dietary fat was demonized and presented as being a problem, we are beginning to see various kinds of healthy fat as part of the solution.Essential Fatty Acids
The omega-3 and omega-6 oils are called essential fatty acids because the body needs them to remain healthy. (Technically, only linoleic acid is an "essential" fatty acid in the strict biochemical sense, because it can not be synthesized by the body and must be ingested with food to support life.) The brain is composed almost entirely of essential fatty acids. Clinically, essential fatty acids (such as flax and borage oils) have a marked anti-inflammatory effect on the body.
Many times, scientific studies run counter to popular beliefs that are often spread via media commercials designed to sell a particular product. One such belief says that we should avoid all fats in order to lose weight. While this is true in the case of simple fats, the essential fatty acids found in high-quality oils are very healthy and may also promote weight loss.
An article in The American Journal of Clinical Nutrition described a study of dietary fish (Mori et. al. 1999). Overweight patients being treated for hypertension were randomly assigned to a daily fish meal (3.65 g of omega-3 fatty acids); a weight-loss regimen; the two regimens combined; or a control group for 16 weeks. Fasting triglycerides fell 29% with fish consumption and 26% with weight loss. The fish plus weight-loss regimen group showed the greatest improvement in lipids: triglycerides decreased by 38% and HDL(2) cholesterol increased by 24% compared with the control group. The authors concluded that adding a daily fish meal into a weight-loss regimen was more effective than either measure alone at improving glucose-insulin metabolism and dyslipidemia (Mori et. al. 1999).
The essential (omega-3) fatty acids found in fish oils are known to promote thermogenesis, the process by which foods are converted immediately to heat. In this way, the body burns off the calories instead of converting them into fats for storage (McCarty 1994). Another benefit of essential fatty acids is to make cell membranes more sensitive to the effects of insulin (Storlien et al. 1986, 1987, 1996; Borkman et al. 1993; Vessby et al. 1994; Pan et al. 1995). As discussed earlier in this protocol, insulin-resistance is a prime factor causing people to gain unwanted fat pounds as they age.
Eating fish is a good way to promote weight loss. Many people also choose to take essential fatty acid supplements that are high in DHA (docosahexaenoic acid) from fish oil extracts and GLA (gamma-linolenic acid) from borage oil. Other options include flax or perilla oil supplements that contain alpha-linolenic acid (precursors to DHA and EPA). Consumption of these essential fatty acids confers a significant protective effect against chronic inflammation and vascular disease, a common problem in overweight people.CHROMIUM
While thyroid hormone plays a definite role in weight management, both magnesium and chromium are also required to break down the cellular insulin resistance that causes higher blood sugar levels.
Overweight people usually experience insulin impairment that prevents the proper carbohydrates (sugars) from being metabolized by their muscle cells. Excessive serum glucose is converted into body fat unless this insulin resistance is broken down and the cells are able to regain youthful carbohydrate metabolism. Chromium has received widespread publicity for its ability to lower serum glucose levels by potentiating insulin sensitivity. Studies have shown that chromium supplementation results in a slight reduction in body fat and an increase in lean body mass. Niacin has been shown to improve the metabolic-enhancing effect of chromium. Chromium polynicotinate may be involved modulating the sensitivity of the insulin receptor, making the cell more sensitive to circulating insulin.
In 1997, Austrian researchers conducted a study to assess the effects of chromium yeast and chromium picolinate on lean body mass during and after weight reduction with a very low-calorie diet: 36 obese nondiabetic patients undergoing an 8-week, very low-calorie diet followed by an 18-week maintenance period were evaluated. During the 26-week treatment period, study subjects received either placebo or chromium yeast (200 mcg/day) or chromium picolinate (200 mcg/day) in a double-blind manner. After 26 weeks, chromium picolinate-supplemented subjects showed increased lean body mass. Researchers reported chromium picolinate, but not chromium yeast, is able to increase lean body mass in obese patients in the maintenance period after a very low calorie diet without counteracting the weight loss achieved (Bahadori et al. 1997).
To improve the fat-reducing effects of dieting, a 200-mcg chromium capsule should be taken with every meal to facilitate youthful carbohydrate metabolism. The importance of taking a chromium capsule with each meal is illustrated in animal studies in which chromium was given throughout the day in order to lower serum glucose levels. When an individual consumes food, serum glucose levels rise significantly unless the cells are sensitized to insulin. Chromium will help sensitize your cells to insulin by helping to lower your blood sugar levels.
Do not take more than three 200-mcg chromium capsules a day. Always take antioxidant supplements such as vitamin E when taking chromium to protect against free-radical activity. At least 30 mg of niacin should be contained in each 200-mcg chromium capsule to facilitate its effects in the body.MAGNESIUM
While chromium has received considerable media attention, the scientific literature shows that magnesium plays an even more important role in regulating carbohydrate metabolism. Magnesium is involved in a number of the enzymatic reactions required for cells to uptake and metabolize glucose. Magnesium deficiency causes insulin resistance and elevated blood sugar levels (Paolisso et al. 1990; Nadler et al. 1993, 1995; Lefebvre et al. 1994).
Approximately 80% of Americans are magnesium-deficient. When magnesium-deficient individuals go on a diet, they often become severely magnesium-deficient, which aggravates insulin resistance and contributes to the failure of the diet. For those individuals going on a calorie-restricted diet, it is suggested that 300-500 mg of supplemental magnesium be taken each day.STEVIA
Stevia is a South American herb (Stevia rebaudiana) that is known locally as "sweet herb" or "honey leaf." Stevioside extracted from this plant is 100-300 times sweeter than table sugar, yet it is not a carbohydrate. Stevia extract and powder can be used as a sweetener both in beverages and in cooking.Continued
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