The male body needs testosterone, its main sex hormone. Testosterone aids in muscle-building, helps grow facial hair and changes the larynx to create a deeper-sounding voice. The female body also produces testosterone, but not as much. Testosterone increases red blood cell growth and stimulates the metabolism, aiding in fat-burning. Some plants produce plant sterols, a type of plant testosterone that is beneficial to the human body.

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Strong male arm with lots of muscles.

Sarsaparilla

Sarsaparilla, a source of natural plant sterols, has long been used by many cultures to boost virility. Sarsaparilla is commonly used in root beer to create the sharp, sweet taste associated with the drink.

Sarsaparilla is a type of herb native to parts of Central and South America. Place sarsaparilla plants in full to partial sunlight, in well-drained soil. Sarsaparilla will not grow in temperatures below 53 degrees F.

Puncture Vine

Tribulus terrestris, more commonly known as puncture vine, has raised testosterone levels in test subjects during scientific studies. Puncture vine, which is rich in varied plant sterols, is native to Eastern Europe and India.

Puncture vine grows well throughout the United States, and in some regions is considered invasive. The plant flowers from April through August in almost any type of soil but it will not grow in the shade.

Nettle

European studies have shown that nettle root may help in replacing testosterone levels in the human body. Nettle is well known for its "stinging" properties; the foliage of the plant causes a skin rash if mishandled. Wear gloves when harvesting or weeding nettle to protect your skin.

Nettle plants grow close to the ground in a round, spread-leaf pattern resembling lettuce. Nettle is easy to grow, and can grow throughout most of the United States. The tiny hairs or bristles covering the plant create the stinging,sensation, so plant nettles away from areas where children or animals may come into contact with it. Edible nettle plants are high in nutritional value, and they've been used medicinally for centuries.