November 10, 2003

20 Min Read
Weight Management


Weight Management

by Susan Colebank

The theory behind maintaining weight seems easy enough: The energy brought into the body (food) must match the energy expended by the body (metabolism). Skew one of these factors, and it has an effect on body composition. Too much food and not enough movement equals weight gain; a lot of exercise and little food, weight loss.

Research indicates being overweight or obese is not only caused by an imbalance between energy intake and expenditure, but also by a pathogenesis in the feedback systems involving leptin, neurochemicals in the brain, and the neural and endocrine messages that respond to the intake of food.1 These secretory products of fat cells and the increased mass of fat reportedly are responsible for associated metabolic diseases such as diabetes, hypertension, heart disease, sleep apnea and certain cancers. For example, research suggests that obesity amplifies oxidative stress, which triggers oxidative development of insulin resistance in men a factor in diabetes development.2

Some researchers suggest current theories about how a person becomes overweight and even obesei.e., energy in vs. energy outare contradictory.3 They argue that if more calories are consumed than used up, obese people should have excess energy. However, obese people instead experience fatigue and decreased physical endurancewhich indicates diminished energy supply in the body.

Why does this occur? In the end, obesity may be linked to a changed metabolism, forcing people to overeat and save energy to sustain the metabolic functions of cells. It is even reasoned obesity may be the effect of environmental factors that activate chronic low-grade inflammation.

Research has indicated that being overweight or obese in adulthood is associated with a shorter life expectancythe same as is seen with smoking.4 Obesity in adulthood is a powerful predictor of death at older ages, researchers concluded. Because of the increasing prevalence of obesity, more efficient prevention and treatment should become high priorities in public health.

George Bray, M.D., from Pennington Biomedical Research Center in Baton Rouge, La., concluded, Treatments consist of techniques to alter the balance between energy intake and energy expenditure.5

Minerals

Fighting off fat may be as simple as taking a mineral; certain ones, such as calcium, have been seen to benefit weight loss by regulating energy metabolism.6 A research review out of Purdue University in West Lafayette, Ind., showed calcium may ultimately play a substantial contributing role to weight loss, as well as to the prevention of weight gain, in both men and women.7 Calcium is used by 36.8 percent of weight managers, according to the Natural Marketing Institute (NMI), compared to 36.3 percent of the general population.

Aside from its potential role in facilitating weight loss, calcium may be important for high-protein dieters, as these diets may contribute to an increase in urinary calcium loss and eventual bone loss, according to researchers from the U.S. Department of Agricultures Jean Mayer Human Nutrition Research Center on Aging in Boston.8

Another mineral, chromium, may influence weight, too. Chromium is used by 5.2 percent of weight managers, according to NMI, which is higher than the percentage of general users of chromium (4.7 percent).

In a review conducted at the University of Exeter in England, researchers assessed the evidence of chromium picolinate for reducing body weight.9 The reviewers reported chromium had a relatively small effect compared with placebo for reducing body weight.

However, when combined with a diet and exercise regimen, chromium picolinate may be more effective in fighting fat than placebo.10 In one study, 122 subjects took chromium picolinate (as Chromax by Nutrition 21 in Purchase, N.Y.) for three months, after which time the treatment group exhibited a more significant loss of weight and fat mass than the placebo group. And, according to a research article out of the University of Alabama, Tuscaloosa, chromium has a role in maintaining proper carbohydrate and lipid metabolism in mammals.11

Chromiums effects on weight and other physiological factors have appeared in other studies, too. Researchers out of Washington reported diabetic rats receiving a combination of chromium nicotinate (as Benicia, Calif.-based InterHealths ChromeMate) and Maitake mushroom watersoluble fraction experienced a greater reduction of body weight, blood pressure and fasting blood glucose levels than diabetic rats receiving either Maitake mushroom water-soluble fraction alone or the control diet.12

Botanicals

When talking about weight management tools, the conversation usually steers toward botanicals. Ever since ephedra became an outcasthaving been officially banned from sale in three states as of October 2003 manufacturers have been looking for the next ephedra, only without the potentially negative side effects.

Green tea

may be one such option, since it has some of the same mechanisms of action as ephedra. Swiss researchers reported green tea extract stimulates brown adipose tissue thermogenesis to an extent that is much greater than can be attributed solely to its caffeine content and may be due to an interaction between the teas catechin and caffeine with sympathetically released noradrenaline.13 In an earlier study, the same researchers noted the combination of caffeine and epigallocatechin gallate (EGCG) increased 24-hour energy expenditure compared to placebo.14

The green tea extract AR25 (as France-based Arkopharmas Exolise), an 80-percent ethanolic dry extract standardized at 25-percent catechins expressed as EGCG, led to a 4.6-percent weight decrease and a 4.5-percent reduction in waist circumference in a three-month open study of moderately obese patients.15

Green tea may also work on other health parameters. In a study out of Japan investigating the effect of powdered green tea on lipid metabolism, the powder inhibited cholesterol synthesis, as well as prevented weight gain and an increase in adipose tissue.16 Japanese research indicated that by suppressing lipid metabolism, green tea also suppressed fatty accumulation and body weight increases, and decreased leptin levels which research indicates are tied to obesity.17 In general, teaincluding green, oolong and black teasmay be able to reduce the effects of hyperlipidemia and prevent weight gain due to its ability to absorb fat.18

Another compound that may work against the bodys circulating fats is grapeseed extract. According to researchers out of New Jersey, grapeseed extract is rich in compounds that inhibit lipases.19 In particular, the extract may reduce the levels of circulating free fatty acids that have been linked to insulin resistance in obese patients, as well as limit dietary fat absorption and the accumulation of fat in adipose tissue.

One hot botanical in the fat-fighting realm is Lagerstroemia speciosa (L. speciosa), which has potential in both weight issues and associated diabetes. Its active constituentsellagitannins, lagerstroemin, flosin B and reginin Aincrease glucose uptake and could be behind the lowering of blood glucose.20 In a randomized clinical trial involving Type II diabetics, subjects receiving a daily dose of 32 mg or 48 mg of L. speciosa (as OptiPures Glucosol, renamed GlucoTrim) showed a 30-percent decrease in blood glucose levels.21 According to researchers from the college of Osteopathic Medicine in Athens, Ohio, L. speciosas effect on glucose transport may be useful for preventing and treating hyperglycemia and obesity in type II diabetics.22

Another ingredient affecting blood sugar levels and weight is Garcinia cambogia. In a four-week study using 3.3-percent garcinia extract on 10-percent sucrose-loading mice, the herb was found to have no effect on body weight, fat pad weight or serum glucose level.23 On the other hand, serum insulin and leptin were lower in the treated mice than in the control group.

Garcinias (-)-hydroxycitric acid (HCA) may be the defining factor in weight management, reportedly due to its effects on curbing appetite and inhibiting body fat biosynthesis. In an animal study, HCA-SX (as Super CitriMax from InterHealth) inhibited serotonin in the brain in a manner similar to that of selective serotonin reuptake inhibitors (SRRIs) such as Prozac.24 This attribute may be beneficial in controlling appetite, as well as treating depression, insomnia, migraine headaches and other serotonin-deficient conditions.

HCA may not only dull hunger pangs, but it may also imbue more energy. Japanese research showed chronic administration of HCA promoted lipid oxidation (a weight-loss factor) and spared carbohydrate utilization during both rest and activity.25

HCA may also have an effect on BMI and the obesity hormone leptin.26 Moderately obese subjects receiving 2,800 mg of HCA (as Super CitriMax) experienced a 4.8-percent loss in body weight and a 6.8-percent improvement in BMI after eight weeks while the placebo group lost only 2-percent body weight and 2-percent BMI. Plasma leptin, a biomarker of the gene that regulates body weight, was reduced by 40 percent in the HCA group, but increased 1.1 percent in the placebo group.


Image: Weight Managers' Daily Use of Supplements

Citrus aurantium

(C. aurantium), also known as zhi shi or bitter orange, is thought to be a thermogenic, thereby offering specific benefits in weight management. A well-accepted theory in terms of weight-loss is that beta agonists, especially beta 3 agonists, can affect body weight and fat mass. Ephedrine alkaloids are known to work at this level by increasing thermogenesis and quenching appetite. C. aurantium also contains beta agonists but has not been seen to have the risky side effects that are synonymous with ephedra. Researchers out of Georgetown University, Washington, reported that, as such, C. aurantium may be the best thermogenic substitute for ephedra.27 In a study of zhi shi, caffeine and St. Johns wort, researchers concluded the combinationin addition to mild calorie restriction and exercisesafely and effectively promoted weight and fat loss.28 [Editors note: The trademark for zhi shi extract, known as Advantra Z, belongs to Burlington, Vt.-based Zhishin LLC, although Wayne, N.J.- based Nutratech has license to sell it.]

Coleus forskohlii and its root extract forskolin have been seen to reduce fat, leaving increased lean muscle mass. In an eight-week study, 500 mg/d of forskolin (as ForsLean from Piscataway, N.J.-based Sabinsa Corp.) significantly decreased body weight and fat content, but increased lean body mass in six overweight women.29 In another study, again involving six overweight women, 250 mg of forskolin taken twice daily 30 minutes before meals for eight weeks reduced body mass without negatively affecting blood pressure.30

In a typical Western diet, 200 g/d to 300 g/d of carbohydrates are consumed on a daily basisan excess of which turns into sugar and, if not used by the body, fat. White kidney bean may hold the answer to preventing carb-associated weight gain. In one study, 50 subjects were randomly assigned to receive a white kidney bean extract (as Phase 2 from Kearny, N.J.-based Pharmachem Laboratories) or placebo for eight weeks.31 Subjects taking the extract lost an average of 3.8 pounds, which was approximately 200-percent more than the loss experienced in the placebo group. Those on the extract also lost 1.5 inches from their waists, which was 43-percent more than the reduction seen in the placebo group. A similar study conducted in Norway showed of 62 overweight and obese adults, those taking the bean extract (as Phase 2) for three months had improvements in serum cholesterol and increases in fecal fat excretion.32 In a study out of Italy, 60 healthy, overweight volunteers ranging from 20 to 45 years old were placed on a recommended dietincluding one meal made up of complex carbohydratesand given either a placebo or a placebo plus 500 mg of a kidney bean extract (as Phase 2 in the product Blockal).33 Participants on the extract lost an average of 6.5 lbs.

Other Weight Managers

There are many nutraceuticals that influence weight, including hormone metabolites, fatty acids, shellfish derivatives and protein. For instance, a metabolite of dehydroepiandrosterone (DHEA), 7-oxo-DHEA, may be effective for promoting weight loss and preventing weight gain. In research out of New York, researchers found the metabolite could aid in fat loss, too.34 In an eight-week study using 30 subjects, those taking 7-oxo- DHEA (as 7-Keto from Chanhassen, Minn.-based Humanetics Corp.) lost more weight (6.3 lbs. vs. 2.1 lbs.) and more fat (1.8 percent vs. .57 percent) than the placebo group. In a study out of Minnesota, of 35 adults, those taking 7-oxo-DHEA (as Humanetics 7-Keto Naturalean, which also contains minerals, L-tyrosine and asparagus root extract) lost more weight and had a greater change in BMI than those in the placebo group.35

Another metabolite, HMB (-hydroxy--methylbutyrate), is derived from the amino acid leucine and has also been seen to work against fat gain. Researchers found it increased fat-free mass in doses of 3,000 mg/d to 6,000 mg/d over an eight-week period.36 And, during a three-week study, HMB combined with creatine increased lean body mass and strength.37

Five days of creatine supplementation was shown to increase body weight and fat-free body mass in resistance-trained men.38 Thirty-two men accustomed to weight training were randomly assigned to receive either creatine (20 g/d plus 180 g/d of dextrose) or placebo (200 g/d of dextrose) for five days. Researchers noted not only an improvement in training, but also a significant increase in body weight and fat-free mass, with the magnitude of increase being significantly greater in the responder group than the placebo group.

Thought of more as a sports nutrition ingredient than a weight management tool, L-carnitine appears to promote healthier body weight through fat loss rather than lean muscle loss. A study of 100 obese people randomly assigned to take either L-carnitine (as L-Carnipure L-carnitine crystalline from Fair Lawn, N.J.-based Lonza) or placebo in conjunction with diet and moderate exercise indicated those in the treatment group had a 25-percent greater loss in body weight than the control group, possibly due to optimized fat oxidation (factor in fat loss).39 Subsequent research with L-carnitine (as L-Carnipure) supported the nutrients role in fat oxidation.40 Researchers at the University of Leipzig in Germany discovered oral L-carnitine increased long-chain fatty acid oxidation in vivo in subjects with no L-carnitine deficiency or without prolonged fatty acid metabolism.

Another fat-fighter is conjugated linoleic acid (CLA). In a 12-week study out of Norway, research showed supplemental CLA (as Tonalin CLA, the trademark for which is exclusively licensed to Cognis Nutrition & Health in La Grange, Ill.) can reduce body fat in healthy subjects when taken in combination with 90 minutes of strenuous exercise three times per week.41 A similar study involving 53 healthy subjects garnered comparable results: Those in the CLA group (taking Tonalin) exhibited a 3.8-percent reduction in the proportion of body fat, but no change in body weight.42

The reason behind CLAs fat-effecting ways may be due to a particular isomer. In a study out of Ohio State University, Columbus, a supplement containing mixed CLA isomers (primarily 9c,11t and 10t,12c) or a supplement containing safflower oil was given to volunteers for eight weeks.43 Plasma levels of CLA were seen to be inversely associated with body weight and serum leptin levels. When levels of plasma 10t,12c were correlated with changes in body weight or serum leptin, 10t,12c, but not 9c,11t, was inversely associated with body weights and serum leptin. These findings strongly suggest the 10t,12c isomer may be the bioactive isomer of CLA to influence the body weight changes observed in subjects with Type II diabetes. (This research received support from Lake Bluff, Ill.-based Pharmanutrients, makers of CLAOne, and Cognis.)

CLAs 10t,12c isomer is also able to suppress increases in blood pressure during the onset of obesity in rats.44 After three weeks of feeding with 10t,12c, systolic blood pressure was significantly lowered compared with rats fed linoleic acid or 9c,11t. Abdominal adipose tissue weight was also significantly lowered in rats fed 10t,12c, but not in those fed 9c,11t.

Appetite (hunger, satiety and fullness) has also been seen to be favorably, dose-independently affected by CLA.45 During a 13-week study out of The Netherlands, 54 moderately overweight men and women were first prescribed a very-low-calorie diet (2.1 MJ/day) for three weeks, after which they started with the 13-week intervention period. They received 1.8 g/d or 3.6 g/d of CLA, or placebo. Additionally, subjects on the high-dose CLA replaced lunch with a protein-rich, low-energy supplement. The mean body weight loss was 6.9 percent. However, CLA was not shown to increase the odds of keeping the weight off after weight loss.

Contrarily, an unpublished study showed CLA did prevent weight gain after a 12-month weight-loss period. Preliminary research sponsored by Cognis and conducted by researchers at Scandinavian Clinical Research in Norway showed CLA (as Tonalin) prevented the regain of body fat after two years of supplementation. The one-year continuation of the original one-year, double blind, placebo-controlled study of 180 overweight subjects indicated CLA supplementation for a second year prevented subjects from regaining the 8-percent body fat loss they attained during the first year. And, subjects who had been taking placebo for the first year and switched to CLA for the second year exhibited a 5-percent loss of body fat.

Taking CLA also appears to help dieters feel better when losing weight, according to researchers from the University of Wisconsin Beers-Murphy Clinical Nutrition Center.46 Of 60 obese subjects on a low-calorie diet for 12 weeks, followed by a 16-week weight regain period, those taking CLA (as Lipid Nutritions Clarinol CLA) experienced a decrease in adverse events usually associated with low-calorie dietssuch as skin rash, irritability, anger, depression and hair losscompared to patients taking placebo. The CLA group also lost more weight overall and gained more lean body mass, and females in the treatment group lost more total and fat weight than the placebo group.

Losing fat mass not only involves increasing lean muscle mass, but also getting rid of the source itself. Chitosan, derived from the exoskeletons of shellfish, is a believed fat-blocker. Chitosan (as LipoSan Ultra from Redmond, Wash.-based Vanson Halosource Inc.) appears to be effective in facilitating weight loss and reducing body fat in overweight and mildly obese individuals, as shown by an eight week study involving 59 women with a history of high-fat diets.47 Even though subjects were instructed to continue their regular caloric intake, the chitosan group experienced decreased mean body weight and body mass index, while subjects in the placebo group experienced an increase in mean weight, body mass index and percent body fat, as well as a decrease in lean body mass.

Chitosan seems to not only help with weight loss, but also cholesterol and blood pressure levels. Orally administered chitosan appears to bind lipids in the small intestine and reduces cholesterol absorption.48 In a study investigating the efficacy of chitosan in reducing serum cholesterol without concomitant diet therapy, 90 hypercholesterolemic women (ages 34 to 70 years old) were randomly assigned to receive chitosan (1.2 g/d) or placebo in a double blind manner. Chitosan significantly reduced total cholesterol compared to placebo, and in a subgroup of women over 60, chitosan significantly reduced total and LDL cholesterol compared with placebo.

Both weight and blood pressure dropped in another chitosan study. In a study that investigated the role of chitosan as a possible adjuvant in obesity, 50 obese women followed a six-month program in which they met with a physician, psychologist and dietitian, ate 1,000 calories a day, and exercised.49 Those in the chitosan group (receiving 4,500 mg/d of chitosan, as Chitinin from Primex Ingredients ASA in Avaldsnes, Norway) lost significantly more weight (35 lbs.) than the placebo group (24 lbs.). The chitosan group also exhibited a reduction in systolic and diastolic blood pressure.

Chitosan, along with the dietary fiber glucomannan, has demonstrated hypocholesterolemic effects as well. In a four-week study out of the University of Minnesota, St. Paul, 21 overweight subjects with normal cholesterol levels were fed 2.4 g/d of a supplement containing equal amounts of chitosan and glucomannan.50 Even though subjects maintained their normal dietary and activity patterns during the study, serum total, HDL and LDL cholesterol concentrations were found to be significantly lower by the end of the study.

Fiber

in general is a good weight management tool. This ingredient is used by 8.3 percent of weight managers, according to NMI, which is higher than the percentage of general users of fiber (5.2 percent). In a cross-cultural study of 13,000 middle-aged men in seven countries, Dutch researchers found fiber intake may be inversely associated with fat mass.51 More specifically, job-related physical activity and dietary fiber intake, but not dietary fat, were important determinants of a healthy weight.

Tufts University researchers reported there were non-significant trends indicating fiber consumption reduced hunger compared to controls and also increased compliancy among dieters.52 Although this news does not sound very convincing for using fiber for weight loss, researchers at the University of California, Davis, reiterated the sticking point behind fiber: Increased fiber intake appears to prolong a persons feeling of satiety.53

In addition, there may be a role for nonfermentable fiber (NFF) and fermentable fiber (FF) in the weight-loss game.54 Researchers out of Tufts University, Boston, compared 27 0.6 g/d supplements of FF (such as pectin, beta-glucan) and NFF (such as methylcellulose) for their ability to decrease food intake and hunger pangs, increase satiety, and cause spontaneous body weight and fat losses. Both normal and overweight men and women consumed first NFF and then FF for three weeks each. NFF was found to be more satiating than FF, although neither NFF nor FF preparations were associated with body weight or fat loss.

Perhaps the most popular ingredient being eyed by todays weightconscious consumers is protein, which is said to regulate food intake through satiety related to diet-induced thermogenesis.55 Protein also plays a key role in body weight regulation through its effect on thermogenesis and body composition. Protein is reportedly more satiating than carbs or fat in the short term, over 24 hours and in the long term. Protein consumption also results in less weight being regained after dieting ends. Animal protein induces a higher thermogenesis than vegetable protein, supposedly, but the scientific community is assessing the possibility of replacing dietary protein with amino acids or peptides that may have a similar impact on weight regulation.

Two studies out of Philadelphia, among the first to examine the health effectsbeyond just getting to a healthy weightof a low-carb/high-protein diet for longer than 90 days found patients on the diet lost more weight and kept it off longer than individuals on a more traditional low-fat weight-loss plan. In the first study, 132 severely obese subjects were put on a carb-restricted diet or a calorie- and fat-restricted diet.56 Those on the low-carb diet lost more weight than those on the low-fat diet and had greater decreases in triglyceride levels. Insulin sensitivity also improved more among patients on the low-carb diet. The second study involved 63 obese men and women assigned to a low-carb or low-fat diet.57 The low-carbers were found to lose more weight than those on a low-fat diet, but the low-carb diet was associated with greater improvement in some risk factors for coronary heart disease, including increased HDL cholesterol and decreased triglyceride levels.

One source of proteinsoyappears to be doing well for weight losers and their health, including benefits on cholesterol and insulin levels. A soy-based meal replacement may reduce body weight, fat mass and even bad (LDL) cholesterol, according to researchers out of the University of Alabama, Birmingham.58 In a 12-week study of a low-calorie, soy-based meal replacement, 100 obese volunteers were randomized to either receive the meal replacement treatment or a control. The treatment group lost significantly more weight than the control group (15 lbs. vs. 6 lbs.) and had a greater change in total and LDL cholesterol.

According to science out of Japan, soy protein may decrease body fat content plus plasma glucose levels.59 Researchers investigated the effects of a soy protein diet on body fat composition, plasma glucose and lipid levels in obese mice. Body weights and adipose tissue weights of mesenteric, epididymal and brown fat were lower in mice on a calorie-restricted diet containing soy protein isolate. Plasma cholesterol, triglyceride, free fatty acid and glucose levels were also decreased by this diet. And, body fat content in mice was seen to be lower in the soy group than in the placebo group.

In a review of soy and weight management, researchers from the U.S. Department of Agricultures (USDA) Phytonutrients Laboratory out of Beltsville, Md., reported insulin levels improved with a soybased diet.60 In animal models of obesity and diabetes, soy protein has been shown to reduce serum insulin and insulin resistance. In studies of human subjects with or without diabetes, soy protein also appears to moderate hyperglycemia and reduce body weight, hyperlipidemia and hyperinsulinemia, supporting its beneficial effects on obesity and diabetes.

Weight loss goes far beyond just losing pounds and getting a svelte figure. Fewer pounds also pave the way toward a healthier life, be it in the form of lower blood pressure or decreased insulin levels. And, as research shows, there are many nutraceuticals that may help consumers meet their goals for weight-loss and renewed health.

Editors note: For a full list of references to this story, click here.

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