L-Tryptophan
L-Tryptophan (LT) is an essential amino acid, which means that it must be consumed from food since the body cannot make it using other amino acids. It is present in virtually all plant and animal proteins. Once the body absorbs LT, it converts it into 5-hyrdoxytryptophan (5-HTP), and then into the neurotransmitter serotonin. It is primarily the serotonin which then does all the wonderful things attributed to LT. For example, serotonin is the precursor to the sleep hormone, melatonin.

Given LT’s relationship to serotonin, it’s no surprise that it is an effective sleep aid. Certainly LT has significant sedative-like properties, although unlike other sedatives it does not appear to impair performance. Specifically, LT is not associated with impairment of visuomotor, cognitive, or memory performance, nor does it elevate threshold for arousal from sleep.

At least 20 years worth of research (including 40 controlled studies) has demonstrated that LT can help induce sleepiness in humans. The weight of the evidence suggests that doses of 1 gram or more is effective. In younger insomniacs, LT is effective in inducing sleep the first night of administration, while in more chronic, well established insomnia or in more severe insomnias, repeated administration of low doses of L-tryptophan over time may be required for therapeutic improvement.

One particular study found that LT may be effective in doses lower than 1 gram. In 15 mild insomniacs 1 gram of LT helped reduce the amount of time it took to fall asleep, although lower doses of 1/4 g and 1/2 g produced a trend in the same direction. Stage IV sleep was significantly increased by 1/4 g of L-tryptophan.

Melatonin
Melatonin is a hormone produced by the small, pea-shaped pineal gland located in the brain. During daylight hours, light entering the eye stimulates neurons to transmit impulses to the pineal gland that inhibit melatonin secretion. But at night, the pineal gland is able to release melatonin.

As the body ages, it produces less melatonin—which may explain why elderly people often have difficulty sleeping and why melatonin supplements improve sleep in the elderly. This does not mean that the use of melatonin should be limited to the elderly. Other research has shown that non-elderly adults with insomnia can also have lower melatonin levels. Also, research has demonstrated that melatonin even helps facilitate sleep in young adults. Research conducted on melatonin showed good results got sleep.

Valerian root
Valerian root is considered by many to be the “granddaddy” of all sleep-promoting herbs, and is the leading herb for insomnia in modern herbal medicine. Valerian root makes getting to sleep easier and increases deep sleep and dreaming. Valerian does not cause the morning “hangover” which is a common side effect of prescription sleep drugs and melatonin in some individuals. By itself, a valerian root supplement (standardized for % valerenic acid), in doses of 300–400 mg can be taken thirty minutes before bedtime. Also, Valerian may be combined with other herbs. For example, one German study compared the effect of a combination product containing an extract of valerian root (320 mg at bedtime) and extract of lemon balm, Melissa officinalis, with the sleeping drug Halcion®. After monitored sleep for nine nights, the herbal duo matched Halcion in boosting the ability to get to sleep as well as in the quality of sleep. However, the Halcion group felt hung over and had trouble concentrating the next day, while those taking the valerian/lemon balm combination reported no negative effect.

Hops
Hops have a history of use as nature’s best sleep “inducer.” Though many natural substances are more effective at keeping one asleep, hops is often considered best at inducing sleep. The German Commission E recommends Hops for anxiety or insomnia.

Passion Flower
Passion flower has been, and continues to be an extremely popular herb in Europe where it is often used to induce relaxation and sleep. In the United States, however, medical use of the herb did not begin until the late nineteenth century when passion flower was used to treat nervous restlessness and gastrointestinal spasms—the belief being that passion flower worked primarily on the nervous system, particularly for anxiety due to mental worry and overwork. Research has demonstrated that the flavonoids in passion flower are the primary constituents responsible for its relaxing and anti-anxiety effects.

Scullcap
Scullcap has been used historically and in modern times as a sedative for people with nervous tension as well as for insomnia. Unfortunately, very few studies have been conducted on Scullcap. However, one double blind, placebo-controlled study of healthy subjects demonstrated noteworthy anxiolytic (anxiety-reducing) effects from Scullcap. Also, one of Scullcaps constituents known as scutellarian has been shown to have mild sedative and antispasmodic actions in animal research.

GABA
Gamma-Amino Butyric Acid (GABA) is a natural peptide which is manufactured from the amino acid glutamine and glucose. In the central nervous system, GABA exerts anticonvulsant, sedative, and anxiolytic effects at the cellular level. GABA supplements appear to promote relaxation and sleep. GABA itself does not cause drowsiness. Instead, by easing anxiety, it simply makes it easier to fall asleep.19

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