What is Guggul? Guggul, also called guggulipid, is an ethyl acetate extract of the gum resin of the guggul tree Commiphora mukul, a small bushy tree found in India, Bangladesh, and Pakistan. This yellowish gum resin has been used for more than 2000 years in Ayurvedic medicine to treat a variety of ailments, and many active constituents have been identified. It has been studied in the treatment of many conditions, including hyperlipidemia, obesity, and arthritis.
What application does Guggul have? Although the majority of studies on guggulipid have been on its cholesterol lowering ability, it has also been identified as a weight loss agent. It activates lipolytic enzymes and increases T3 levels, presumably due to increased conversion of T4 to T3 in the liver, although it may also stimulate the thyroid directly.
Quite a few studies have been done on both humans and animals accessing guggul's ability to stimulate fat loss. Animal studies have shown a positive effect, and human studies have either shown a benefit or have been equivocal. Unfortunately, many of these studies were inadequately controlled. A study that controlled for BMI, concurrent drug use, diet, and exercise found that people who took guggul lost 1.92 kg after 15 days compared with .32 kg in the control group.
How does Guggul work? As stated, orally administered guggulipid increases T3 (tryiidothyronine) levels in animal models. T3 is the conversion product of T4, which is produced by the thyroid gland. Thyroid hormone levels are intricately involved in metabolic homeostasis. Increased thyroid levels cause more fat to be burned and decreased levels increase the likelihood of fat being stored. When one normally goes on a diet, the body responds by decreasing T3 levels and thus decreasing metabolic rate. But if T3 levels are increased, diets are much more effective at causing fat loss. It has not been established how guggulipid increases T3 levels, but the prevailing theory is that it is by decreasing lipid peroxidation.
What Benefits does Guggul have?
Cholesterol Reduction - It is well established that orally administered guggulipid decreases LDL cholesterol and triglyceride (TG) levels while either having no effect on or slightly increasing HDL cholesterol levels. Depending on dosage, it generally reduces LDL and TG levels between 10 to 25 percent. Guggul functions in this respect by decreasing hepatic cholesterol biosynthesis. Two constituents of guggul, guggulsterones E and Z, have been identified as primarily responsible for its hypolipidemic properties, although these are definitely not the only active constituents in guggulipid.
Anti-Inflammatory - Guggulipid is a potent anti-inflammatory agent, as evidenced by many studies done on individuals with arthritis. The compound primarily responsible for the anti-inflammatory properties of guggul is myrrhanol A, which is found in the acidic fraction of the extract.
Reduction in Acne - There are many anecdotal reports of guggul causing a reduction of acne. There has been only one clinical study done, in which guggul was shown to be as effective as tetracycline (an antibiotic commonly used to treat acne).
Reduced oxidative stress - Guggulipid may significantly decrease lipid peroxidation. One controlled study showed a 33% decrease in lipid peroxides after 24 weeks of 50 mg of guggulipid per day.
What are the side effects? The studies do not report serious side effects, although some users experienced gastrointestinal discomfort which did not necessitate discontinuation. High doses have been used without the incidence of ill effects. Guggul may compete with some cholesterol reducing medications, so if you are on such medications you should consult a doctor before taking guggul. Likewise, you should consult a doctor if you have a thyroid disorder.
The primary side effect that the athlete should be worried about is the possibility of muscle catabolism. Increased thyroid levels may also increase mitochondrial uncoupling of muscle tissue and decrease insulin secretion and nitric oxide production. Although fat loss will still be the primary effect, a portion of the weight lost may be from muscle. Fortunately, you can avoid or at least highly limit the amount of catabolism caused by increased thyroid levels by increasing your testosterone levels, because testosterone blocks the pathway through which thyroid-induced protein uncoupling occurs.
What form of Guggul is best? As guggul has various constituents, isolating the desirable ones may increase its effectiveness while reducing unwanted side effects. On the other hand, in the case of many of the constituents of guggul, the activity has not been adequately studied - especially for fat loss purposes - so it may be unwise to leave these out.
Guggulipid standardized for total guggulsterones - The majority of studies - and all of the studies done on thyroid activity - have been done using guggulipid, usually an extract standardized to 10% guggulsterones. As it contains all of the constituents, this extract should stimulate the thyroid and have anti-inflammatory and hypolipidemic activity. The extract can be further divided into neutral, acidic, and basic portions. The acidic portion possesses the anti-inflammatory activity, while the neutral portion is hypolipidemic. The hypolipidemic portion has been studied in detail, and the E and Z guggulsterone isomers have very strong activity while some of the other isomers have weak activity.
Guggulipid standardized for E- and Z-guggulsterones - Most standard guggul extracts contain .5-2% E- and Z-guggulsterones. Since these are the primary hypolipidemic agents, it is probable that they are also primarily responsible for some of guggul's other effects. Hence, increasing the total amount of E- and Z-guggulsterones may make the formulation much more potent. Products containing higher quantities of E- and Z-guggulsterones may be ideal, but two studies have shown that most products that claim to have higher quantities of E- and Z-guggulsterones than conventional extracts actually do not (12, 13). So, if you are buying a guggul extract that claims to have higher quantities of the E and Z isomers, chances are it isn't much more potent than other extracts despite label claims.
Synthetic E- and Z-guggulsterones - This is a relatively new and promising development. These are just as effective as the E- and Z-guggulsterones derived from guggulipid, but they are much more concentrated. The only downside is that some of the other guggulsterones may have important activity as well. If your goal is cholesterol reduction or weight loss though, synthetic guggulsterones will probably be more effective than a standard guggul extract.
How should I take Guggul? Guggul will be most helpful when thyroid hormone levels are suppressed, such as when you are in a caloric deficit. The effective dose is 50-100 mg of total guggulsterones daily, or 1 mg/kg of body weight, spread out over three doses. With synthetic guggulsterones, a lower amount should achieve the same effect. Cycling is probably not necessary - increased T3 levels can cause natural thyroid hormone suppression, but this effect quickly disappears after discontinuation even with long term use.
