Testosterone booster Tribulus – What the earth star can really do?
– Tribulus terrestris, also called "earth star" or "earth thorn nut", is a widespread plant. It contains saponins. These secondary plant substances are found in many plants, for example in beans, asparagus or soybeans. – Dietary supplements with saponins are said to increase muscle mass in athletes. A positive effect on potency is also claimed. Scientific evidence is lacking for both. – Since products containing Tribulus terrestris have often been found to contain unauthorized added hormones or steroids, there is a risk to health. Positive findings in doping controls are also possible.
What is behind the advertising of Tribulus terrestris??
Food supplements with Tribulus terrestris (also: earth star, earth thorn nut) alone or in combination with other substances are marketed as so-called "testosterone boosters", especially for athletes. Among other things, they are supposed to promote strength and muscle growth (anabolic effect), but also increase libido and potency. This is supposed to work by increasing the concentration of testosterone in the body.
The anabolic effect is attributed to steroid saponins (especially protodioscin, s.u.) attributed.
Although Tribulus terrestris is widely used and touted to "increase the body's testosterone levels by over 40 percent while significantly increasing muscle mass and strength," the claimed anabolic effect has not yet been demonstrated.
Instead, in recent studies with athletes the ineffectiveness was proven. Positive results come only from case reports with few test participants.
The advertising claim that Tribulus extracts are an important source of nitrogen and thus prevent a negative nitrogen balance, which would otherwise prevent muscle building, is particularly contradictory. A negative nitrogen balance would lead to more proteins being broken down than built up, especially in the muscles. However, it only occurs in times of hunger, z. B. by long fasting or in case of severe diseases. You succeed in supplying nitrogen through the abundant protein-. Thus amino acid supply in Germany very good! This also applies to athletes:inside who want to build muscle.
While the "earth star" is used in some countries to treat coughs and headaches, there are no approved medicines containing Tribulus terrestris in Germany. In Ayurvedic medicine it is used for its diuretic effect to treat edema and for enemas. An effect as a sexual enhancer, on the other hand, is unlikely. There are only a few studies on humans. These provide hardly any evidence for a benefit.
There are no health claims for the plant or substances derived from it that have been scientifically tested and approved by the EU Commission (health claims).
What should I look for when using Tribulus terrestris products?
The plant contains alkaloids of health concern, in particular harman and norharman. Whether these genotoxic (mutagenic) and mutagenic (mutagenic) substances are present in dietary supplements containing Tribulus terrestris, and how much of them, is unknown. Overall, there is too little data available to assess a possible risk. Risks from the contained saponins are not to be expected, as the amounts in food supplements are too low. For the adverse effects found in animal studies, much higher intake levels are required.
Tribulus terrestris is considered "not novel in food supplements" according to the Novel Food Regulation. This means u.a., That it has not been eaten by larger populations over a longer period of time, but has only ever been used in dietary supplements. Thus, there is a lack of data that could prove the absence of adverse effects. There are no studies in humans that have systematically investigated such adverse effects. Studies in experimental animals on short-, long-term and developmental toxicity (i.e., "toxicity"), as well as on harm to genetic material and reproductive organs, are also not available.
Due to the poor data situation and remaining uncertainties, the Federal Office of Consumer Protection and Food Safety (BVL) has classified Tribulus terrestris in List B of the List of Substances, category "plants and plant parts. Thus, a restriction is recommended for the plant when used in foods. For the use of above-ground parts of Tribulus terrestris resp. Extracts made from these substances in foods other than food supplements require approval under the Novel Food Regulation.
Until clear safety studies are available, it is better not to consume Tribulus terrestris in the form of food supplements. Above all, these products should not be taken by pregnant women, nursing mothers and children under 12 years of age.
What should athletes watch out for?
The ingredients contained in Tribulus terrestris according to current knowledge are not part of the current World Anti Doping Agency (WADA) Prohibited List. However, there is ongoing debate as to whether extracts of this plant can have an effect on the body's hormone production.
In the case of dietary supplements containing Tribulus terrestris, the National Anti Doping Agency (NADA) warns of the possible danger of containing substances banned for athletes, even if the composition is supposedly purely herbal. Studies show, that a large number of sports supplements contain (intentional) impurities with stimulants, hormones or anabolic steroids. This mainly concerns products from non-European countries, but also from German manufacturers who have products bottled in or for foreign countries. This can lead to positive analysis results regarding the intake of prohibited stimulants or steroid anabolic steroids. According to current WADA regulations, this constitutes doping. The risk is borne by you as the consuming athlete.
The Australian Institute of Sport (AIS) has classified Tribulus terrestris in group D in its "Sports Supplement Framework". These are listed as substances that are banned for athletes or are at high risk of contamination by substances that could lead to a positive doping test.
To be on the safe side, if at all, only take products that are on the Cologne List.
Tribulus products with unapproved ingredients have been repeatedly recorded in the European Rapid Alert System RASFF in recent years.
What is Tribulus terrestris?
Tribulus terrestris, also known as (earth) burr thorn, earth star or earth thorn nut, grows worldwide, often in warm regions such as the Mediterranean area, Central Asia and tropical Africa. The plant contains a variety of saponins, u. a. the steroid saponins furostanol and spirostanol.
Saponins belong to the secondary plant substances. They are contained in 75% of all plant species, i.e. very widespread. They come z. B. found in beans, spinach, peanuts, soy and many Allium species, such as leeks, onions and garlic. Some saponins can have fungicidal, or cholesterol-lowering, effects, but also hemolytic, d. h. certain blood cells can be dissolved. Especially rich in steroid saponins is the yam, but also the asparagus.
In the past, the spirostanol dioscin, which is also found in Tribulus terrestris, was used as a starting material for steroid hormone production. Saponins are difficult to analyze. To be determined in quantity. The amount contained in Tribulus terrestris is. The composition of saponins varies considerably. They depend on the geographical origin, the plant part and the growth phase of the plant. In many dietary supplements, the furostanol protodioscin is highlighted. When comparing plants from different origins, the lowest concentrations of protodioscin are found in plants from India and Vietnam. Higher values are detectable in plants from the southern European region. The fruits usually contain less than the leaves.
What ingredients are contained in Tribulus-terrestris products?
Many products contain, in addition to necessary additives such as release agents, only "extracts of Tribulus terrestris". In most dietary supplements it is not obvious which parts of the plants are used. Many are advertised as having high saponin contents of 80 to 90. High-dose products contain up to 3.600 mg Tribulus extract. Up to 1.800 mg saponins (daily consumption amounts). 600 mg Tribulus extract. Up to 1.800 mg saponins (daily intake).800 mg saponins (daily intake). It is mostly unclear how the extract was prepared or how the saponins are composed. However, some manufacturers indicate the content of protodioscin (often 20-25% of saponins).
In addition to the plant extract, individual dietary supplements also contain the B vitamin pantothenic acid and zinc. This has the advantage for manufacturers that they can advertise with the health claims approved for these substances: "Zinc contributes to the maintenance of normal testosterone levels in the blood and to normal protein synthesis" and "Pantothenic acid contributes to normal synthesis and metabolism of steroid hormones".