How Does Jelly Force Work? The Three Routes On The Label

L-arginine is a semi-essential amino acid and the substrate for nitric oxide synthase. Nitric oxide diffuses into the smooth muscle of a blood vessel wall, raises cyclic GMP, and the muscle relaxes. A relaxed vessel wall is a wider vessel, and wider vessels carry more blood. That chain is textbook physiology rather than a marketing claim, and it is the same chain a prescription phosphodiesterase inhibitor acts on, one step further downstream.

The evidence that supplementing the substrate moves an outcome is real and it is bounded. Ten randomised trials in 540 men with mild to moderate erectile difficulty were pooled in 2019 (Rhim 2019). Arginine beat placebo with an odds ratio of 3.37, improved the overall satisfaction, intercourse satisfaction, orgasmic function and erectile function subdomains of the IIEF, and left the sexual desire subdomain unchanged. Adverse effects ran at 8.3 per cent against 2.3 per cent on placebo, none severe.

The 2024 network meta-analysis put the same ingredient in context. Across fifteen randomised trials in 1,000 men, L-arginine ranked above every other nutraceutical tested except a carnitine pair, and its clearest use was alongside a prescription rather than instead of one (Barbonetti 2024). The doses in that literature were 1,500 mg to 5,000 mg a day.

Horny goat weed belongs on the same route, one step later. The signal nitric oxide starts is ended by an enzyme, PDE-5, and prescription tablets for erectile dysfunction work by blocking it. Icariin, the marker compound in horny goat weed, blocks it too in laboratory tests, though it needed about eighty times sildenafil’s concentration for the same effect (Dell'Agli 2008), and it kept cGMP raised in cavernous smooth muscle cells (Ning 2006). That is a mechanism in a dish, not a result in a person: no randomised trial of the herb on its own turns up in PubMed.

Four of the nine names are on the panel because people have used them for a long time, which is a real reason and a weak one. Traditional use tells you a plant was available, tolerated and believed to work. It does not tell you which of those three explains its reputation.

Maca is the exception and deserves separating from the other two. A twelve-week randomised trial in healthy men aged 21 to 56 found self-reported sexual desire improving from week eight at both 1,500 mg and 3,000 mg a day, and the authors went looking for the explanation: serum testosterone and oestradiol did not differ from placebo, and logistic regression showed the effect was independent of the Hamilton depression and anxiety scores too (Gonzales 2002). A second trial in fifty men with mild erectile difficulty gave 2,400 mg of dry extract for twelve weeks and measured a larger IIEF-5 gain than placebo (Zenico 2009).

Muira puama and catuaba have neither. The Brazilian review that compiled seventy-four species used for this purpose lists fourteen with pharmacological study behind them; Trichilia catigua is on that list and Ptychopetalum olacoides is not (Teixeira 2024). What exists for muira puama is mouse work, including an anti-stress study at 100 to 300 mg per kilo (Piato 2010), and a body of chemistry.

Tribulus is the other exception, and the advertising leaves it off. In 180 men with mild or moderate erectile difficulty, 1,500 mg a day of a standardised dry extract for twelve weeks raised IIEF scores more than placebo, with no difference in side effects (Kamenov 2017). A month at 800 mg a day made no difference (Santos 2014), and eight studies pooled in 2026 kept the questionnaire gain while total testosterone stayed where it was (Suharyani 2026). Whatever tribulus does in those trials, raising testosterone is not it; a 2005 trial in young men had already found no change in testosterone, androstenedione or LH (Neychev 2005).

It is a useful exercise to run backwards. For this bottle to do what its roundels say, at least one of four things would need to hold.

One: the extracts are concentrated far beyond what the trials used, so that 82 mg of extract carries the activity of grams of root. The footnote points that way, at roughly seven to one: 567 mg of starting material behind 82 mg. For the whole blend to stand in for the 1,500 mg of maca root in the smallest trial arm, with nothing else in it, the ratio would need to be about eighteen to one.

Two: the nine work together, so that a small amount of each adds up to more than the sum of the parts. That claim is common in this category and has almost nothing behind it. The 2024 network meta-analysis found combinations outperforming single agents only where one of the components was a prescription drug (Barbonetti 2024).

Three: the outcomes people notice are more sensitive than the outcomes trials measure. Plausible, unmeasurable, and precisely the reason placebo arms exist.

Four: the routine itself does some of the work. Taking something every morning for a purpose changes attention and often changes the behaviour around it, and that is not nothing even when it is not pharmacology.

This desk finds the fourth the most defensible and the second the least. Neither belief belongs on a product label, which is why it is written here instead.