' An Act to preserve daylight and provide standard time for the United States ' was enacted on March 19, 1918. [See law] It both established standard time zones and set summer DST to begin on March 31, 1918. Daylight Saving Time was observed for seven months in 1918 and 1919.
Nitrate-rich foods include lettuce, parsley and spinach. âLeafy vegetables contain chemical nitrate that improves heart health,â the Mail Online reports. In a recent study, researchers looked at the effects of a nitrate-rich diet on rats.
Many vegetables, especially root vegetables, grow within the soil and collect high concentrations of nitrates. According to the book âNutritional Sciences,â vegetables high in nitrates include lettuce, beets, carrots, green beans, spinach, parsley, cabbage, radishes, celery and collard greens.hoto Credit Marina Lohrbach/iStock/Getty Images. Nitrate is a salt of nitric acid and found naturally in fruits, vegetables and grains. It is also added to cured meats such as salami, bacon and hot dogs as a color preservative and to retard the growth of microorganisms.