Carbohydrate Blockers

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    Weight Loss Supplements Dallas Clouatre

    Many of us start off the year with a determination—backed by a gym membership— to get into shape and lose weight. It now is February. How are those New Year's resolutions faring? Is it time for Plan B?

    If that means diets and weight loss aids, there is no one-size-fits- all. Choosing the right approach with realistic expectations as to how much can be lost and how quickly will help prevent frustration and disappointment, not to mention major weight regain later in the year. Research in advance is the key. The following are some major categories and rationales for weight loss supplements:

    • Appetite suppressants and mood enhancers
    • Calorie (carbohydrate and/or fat) absorption blockers
    • Diuretics and laxatives
    • Metabolism enhancers and thermogenic agents
    • Nutrient partitioning agents

    Of the above approaches, for many reasons, the most commonly adopted method remains that of metabolism enhancers and thermogenic agents. Typical ingredients for this tactic for weight loss are bitter orange, caffeine, country mallow, green tea, guarana, 7-keto DHEA, synephrine, yerba mate and yohimbe. Inasmuch as one or more of these ingredients can lead to side effects if used incorrectly or by individuals for whom they are inappropriate, the following observations start by examining thermogenic agents.

    How Do Thermogenic Agents Function Within the Body To Burn Fat?
    Thermogenesis literally means causing the production of heat. Aside from the shivering response to cold, body heat production is a side effect of exercise and or of increased basal metabolic rate. The thermic effect of food ideally should be on the order of 10 percent of calories consumed. Thermogenic products are designed to stimulate the metabolism to be above where it normally would be in order to burn additional calories and to access fatty acids for this purpose. The most common approach for achieving this is to manipulate one of the body's hormonal signals, usually norepinephrine. Green tea epigallocatechin gallate (EGCG) reduces norepinephrine degradation and thereby increases catecholamine-mediated stimulation of β-adrenergic receptors and activates the sympathetic side of the nervous system. Ingesting EGCG by itself and in conjunction with caffeine prolongs the actions of norepinephrine. This increases the metabolic rate, hence increases energy expenditure by increasing the oxidation of glucose and fat for energy and increasing calorie-consuming actions. As a rule, there is a significantly greater mobilization and utilization of fat for energy than glucose—in fact, most metabolic stimulants cause fat to be released from storage so that it is more readily available for energy generation. The stimulation involved may make a person more wide awake and even more inclined to exercise, but some of the stimulation may involve what are termed "futile cycles" that consume energy and create heat, but do not lead to physical exertion.

    How Can Those Who Want To Avoid the Negative Effects of Stimulants Benefit From Thermogenic Agents?
    There are at least three side effects that dieters should look to avoid: 1) increased heart rate, 2) increased blood pressure and 3) excessive central nervous system stimulation. One solution to the cardiovascular side of things is to improve the circulation, especially to the heart. Hawthorne extracts help to open the circulation of the coronary artery, that is, the main blood supply to the heart. Herbs such as specialized grape seed extract and wild bitter melon, similarly, are useful for supporting the body in blood pressure regulation. The mineral magnesium is another aid here in that it both helps to regulate blood pressure and is calming to the nervous system.

    Excessive stimulation that overly activates the central nervous system leading to agitation, emotional control issues and/or sleeplessness actually does not usually increase thermogenesis, a fact that emerged from the ephedra-caffeine trials at Harvard and elsewhere. The clearly thermogenic combination of ephedra-caffeine increased energy expenditure at low to moderate doses, but above a not particularly high level of intake the amount of extra calories burned went down rather than up. Moreover, excessive stimulation induces a release of cortisol, which tends to cause the loss of lean tissue rather than fat tissue.

    For Consumers Who Use Caffeine To Increase Their Metabolism, What Are the Concerns Surrounding Caffeine?

    Caffeine definitely is a mixed bag when it comes to metabolism.

    • Looking only at caffeine by itself, there is evidence for acute increases in resting metabolic rate and thermogenesis, but habituation nullifies such benefits with chronic intake.
    • Habitual caffeine use reduces the benefits of caffeine/EGCG mixtures compared to findings in test subjects who do not consume significant amounts of caffeine regularly.
    • Overall, there is little or no support for the claim that caffeine by itself induces or maintains weight loss over the long term.

    In short, caffeine is more useful for metabolic effect if consumed with something like EGCG, such as from green tea, but habituation is rapid. Caffeine-related compounds in green mate appear to have more benefits over the long term than does simple caffeine. The health benefits of coffee, such as they are, come from chlorogenic acid and related compounds, not mainly from the caffeine.

    Keep in mind, an intake of 700 mg or more caffeine per day (about five cups of coffee) is often associated with depression and mood swings. Some authorities draw the line at 600 mg per day. Caffeine causes short-term increases in blood sugar levels that can be followed by dramatic downward fluctuations. Consuming caffeine, in other words, is yet another path to the sugar "roller-coaster" of energy ups and downs and sugar cravings. Cutting out caffeine and refined sugars for as little as one week has been shown clinically to improve mood in many individuals complaining of depression.1

    What Are Some of the Concerns Surrounding Weight Loss Supplements, Such as Synephrine and Yohimbe?
    No doubt, the major concerns are elevated blood pressure and elevated heart rate. In addressing these concerns, the source of synephrine is important. ρ-synephrine is an alkaloid occurring naturally in some plants and animals. A related compound is found in approved drugs as the m-substituted analog known as neo-synephrine. Bitter orange (Citrus aurantium) is a source of ρ-synephrine, which does not seem to increase blood pressure significantly, although it may have an effect on heart rate. ( m-Synephrine, often confused in the literature with ρ-synephrine, exhibits cardiovascular effects, but reportedly is not a constituent of bitter orange. It remains controversial whether ρ-synephrine exerts effects on blood pressure and heart rate if consumed with large amounts of caffeine or other stimulants.

    ρ-Synephrine is used to increase energy expenditure and lipolysis; ρ-synephrine is a β-3 adrenergic receptor agonist, which is to say, a thermogenic compound. By itself, ρ-synephrine as found in bitter orange is not associated with significantly increased blood pressure or heart rate; no significant α-adrenergic effects have been demonstrated, unlike the case with, say, ephedrine.2 Again, synthetic synephrine is a slightly different compound and can lead to high blood pressure and other effects even at relatively modest doses.

    It is neither necessary nor useful to push an intake of ρ-synephrine above approximately 50 mg. Rather, greater energy expenditure is induced by adding 600 mg naringenin to the mixture and a further increase can be induced by adding 100 mg hesperidin. (

    Another widely promoted thermogenic herb is yohimbe (Pausinystalia yohimbe). It is claimed as a thermogenic agent due to its active component, yohimbine, an α-2 receptor antagonist. Three double-blind RCTs, which included patients who were > 15–20 percent over their ideal body weight or had a BMI ranging between 28 and 48 and lasted three weeks to six months, yielded weight loss only at three weeks on a restricted diet, the loss being 1.34 kg greater than with placebo.3 However, yohimbe exhibits erratic effects on blood pressure, heart rate and neurological parameters with a high risk of toxicity.4

    How Do the Satiety Supplements 5-HTP and Hydroxycitric Acid Work?
    Items that affect serotonin, such as 5-HTP (5-hydroxytryptophan) and St. John's Wort, may influence mostly carbohydrate consumption. 5-HTP activates serotogenic pathways and at 600 to 900 mg/day induces weight loss of 3.1–3.7 pounds in 5–6 weeks without dieting. At 900 mg, 70 percent of subjects experienced significant nausea, but adjusted after six weeks.5 Although anyone being treated with pharmaceutical psychoactive drugs should not use 5-HTP without their doctor's agreement, 5-HTP otherwise has been found to be safe at ordinary dosages.6

    (–)-Hydroxycitric Acid / HCA, always sold as a mineral salt, is unusually well studied with at least 12 randomized placebo-controlled trials, but studies have used different salts and widely differing dosages. Mechanisms of action remain controversial. HCA does not cross the blood-brain barrier, hence does not influence the central nervous system directly; neither does it depend on activating nerves involving the liver (vagal afferents). HCA delays gastric emptying, however, and it prolongs glucose absorption from the small intestine. The primary effects seem to be to reduce between-meal snacking and to increase the length of time that dieters feel satiated after meals. Potassium and potassium-magnesium HCA salts are insulin sensitizing at human acceptable dosages whereas calcium- and calcium-potassium HCA salts are not. Apparently no one has tested the socalled "triple" salts even in animals. Weight loss in randomized controlled trials (RCTs) ranges from none to approximately 1/2 to one pound per week for eight weeks at higher dosages (2.8 g HCA) of potassium-based salts. In other words, approximately 4.5 grams/day of a potassium-based salt can lead to as much as one pound per week weight loss if taken as directed. Weight loss normally starts after the first or second week of usage for reasons having to do with refilling glycogen stores in the liver and muscle as well as greater hydration of muscle tissue. No toxicity or significant side effects have been found with properly manufactured HCA salts in controlled trials and safety reviews. Despite extremely widespread usage for roughly 25 years, only a handful of adverse event reports have appeared, usually with combination products and/or in cases in which the report could not even name the HCA salt involved.7,8

    Do Chia Seeds and Similar Foods Promote Satiety?
    Good fiber sources, especially very viscous fibers, increase satiety by increasing stomach distention (the feeling that the stomach is extended and full) and reducing the rate of gastric emptying. They also tend to reduce the rate at which carbohydrates release glucose into the blood stream. Viscous soluble fibers include, but are not limited to pectins, β-glucans, psyllium, glucomannan and guar gum. Foods such as ground flax seed, baked acorn squash, artichoke hearts and most legumes are good fiber sources. Oats and barley are good items, but not if they have been "instantized" since this process causes them to act more like high-glycemic foods.

    Protein sources also are good for satiety, although one can over-consume calories from protein just like anything else. Plant protein sources are slower to be absorbed into the tissues and thus may be especially good for prolonging satiety. At the other end of the scale, fructose is a particularly bad sugar for dieters and for health in general. Indeed, it is significantly worse than glucose or sucrose according to recent research.

    How Do Fat and Carbohydrate Blockers Aid in Weight Management?
    White kidney bean extracts and a number of other products, including bitter melon, inhibit carbohydrate digestion by inhibiting the actions of alpha-amylase and/or related compounds. The drawback of these in the American diet is that more and more calories in our diet are from corn sugar and other simple sugars. Indeed, corn sugars often are the cheapest binders and fillers available for processed foods. Carb blockers may be helpful with traditional foodstuffs, but this is modern America. Corn is subsidized and processed corn components are everywhere.

    HCA reduces the rate at which carbohydrates are available, but it is not a traditional carbohydrate blocker. Its mechanism of action is different in that it slows and prolongs the passage of glucose across the gut membrane into the blood stream via its effects on the sodium pump in the gut. There likely are a small number of other supplements that work similarly.

    A well-known lipase inhibitor (blocker of fat digestion) is derived from Cassia Nomame Mimosoides. This item was created to mimic the actions of a pharmaceutical weight loss product that inhibits the absorption of 30 percent of fat found in the diet. Concerns are sometimes expressed as to the wisdom on preventing the proper digestion of fats in the small intestine. Unlike carbohydrates, which can be acted upon by various bacteria in the large intestine, the body is poorly equipped to chronically handle fats not digested in the normal fashion. At this point in time, even the pharmaceutical fat blockers have largely disappeared and no trials seem ever to have been undertaken to demonstrate the efficacy of "natural" fat blockers claimed to be natural alternatives to the drugs.

    Begin with Your Eating and Exercise Habits
    To repeat a point made in articles in the past, diets that are inadequate in terms of vitamins and minerals, and in many cases protein, often coincide not only with weight gain, but also with low energy levels and mood swings. The consumption of a diet based largely upon sugars, refined carbohydrates, soft drinks and "junk foods" in general is just not sufficient to maintain good bodily health. If the overall quality of health is poor, it is unlikely that mental functioning and emotional well-being will fare any better. A powerful incentive for binge eating and a source of sugar cravings is the effort to counter depression and mood swings.

    Remember, as well, the place of exercise. Exercise is less important for its role in directly burning calories than for increasing basal metabolic rate in the morning and helping the body to access fats for energy. As little as 20 to 30 minutes walking every day can help the body to relearn how to burn fat for fuel. Walking early in the day has the added benefit of speeding up the metabolism when this can do the most good and also providing a daily dose of mood-brightening sunshine. Before or after the evening meal are two other good times to take a walk.


    1. Kreitsch, K., et al. Prevalence, presenting symptoms, and psychological characteristics of individuals experiencing dietrelated mood disturbances, Behav Ther 1988;19:593–604.
    2. Stohs SJ. Safety, Efficacy, and Mechanistic Studies Regarding Citrus aurantium (Bitter Orange) Extract and ρ-synephrine. Phytother Res. 2017 Oct;31(10):1463–74.
    3. Pittler MH, Ernst E. Dietary supplements for body-weight reduction: a systematic review. Am J Clin Nutr. 2004 Apr;79(4):529–36.
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    5. Cangiano C, Ceci F, Cascino A, Del Ben M, Laviano A, Muscaritoli M, Antonucci F, Rossi-Fanelli F. Eating behavior and adherence to dietary prescriptions in obese adult subjects treated with 5-hydroxytryptophan. Am J Clin Nutr. 1992 Nov;56(5):863–7.
    6. Das YT, Bagchi M, Bagchi D, Preuss HG. Safety of 5-hydroxy-L-tryptophan. Toxicol Lett. 2004 Apr 15;150(1):111–22.
    7. Chuah LO, Yeap SK, Ho WY, Beh BK, Alitheen NB. In vitro and in vivo toxicity of garcinia or hydroxycitric acid: a review. Evid Based Complement Alternat Med. 2012;2012:197920.
    8. Márquez F, Babio N, Bulló M, Salas-Salvadó J. Evaluation of the safety and efficacy of hydroxycitric acid or Garcinia cambogia extracts in humans. Crit Rev Food Sci Nutr. 2012;52(7):585–94