• L-Citrulline is an amino acid that boosts nitric oxide in the body, which improves blood flow and plays a role in biological function.
• L-Arginine is an amino acid that helps your body produce proteins. Proteins are essential because every cell in your body contains proteins.
• Black Pepper Fruit Extract (Piper Nigrum), especially its active ingredient piperine, helps enhance nutrient absorption of the supplements.

• Ashwagandha: The herb with the most research behind it. One study tested the effects of this herb on infertile men and found a 17% increase in testosterone levels and a 167% increase in sperm count. In healthy men, ashwagandha increased levels by 15%.
• Vitamin D: In a recent study, the results suggested that vitamin D supplementation might increase testosterone levels.
• Maca: Some evidence suggests Maca may help boost libido and sexual desire—and have been used for centuries in the Andes to treat conditions like fatigue and low stamina.
• Fenugreek: Several studies have shown that taking fenugreek supplements may improve testosterone levels and symptoms related to low testosterone such as low libido.
• Zinc: In one study, zinc may play an important role in supporting healthy serum testosterone levels.

Tongkat:

A study found that taking tongkat ali extract per day significantly increased levels of testosterone to healthy values.

Testosterone is a hormone that your gonads (sex organs) mainly produce. More specifically, the testicles in people assigned male at birth (AMAB) and the ovaries in people assigned female at birth (AFAB) produce testosterone. While, Libido is just another name for sexual desire or the sex drive.