Several human studies have measured the effects of melatonin supplements on sleep in healthy people. A wide range of doses has been used, often taken by mouth 30 to 60 minutes prior to sleep time. Results have been mixed. Some evidence suggests that melatonin may work best for people over 55 who have insomnia.
Dar es Salaam, the largest city and former capital of Tanzania, is located on the coast, in the area with two rainy seasons, and is hot all year round, with a slightly hotter and wetter period from November to April, when daytime temperatures are around 31/32 Â°C (88/90 Â°F), but with peaks of 35/36 Â°C (95/97 Â°F), and relative humidity is high, especially in March and April, the rainiest months.
1 Arusha, Tanzania is at 3 20'S, 36 37'E, 1387 m (4551 ft).2  See map. 3  According to the Holdridge life zones system of bioclimatic classification Arusha is situated in or near the subtropical moist forest biome. If you were to burrow down through the Earth from Arusha you would come out nearest to the climate station at Atuona, French Polynesia where you would find a Tropical wet climate.