' 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.
Luckily, beetroots are just one of many vegetables and herbs that are high in nitrate. Leafy green vegetables tend to be the top sources of nitrate: 1  High nitrate levels (~100-250 mg/100 g): basil, celeriac, Chinese cabbage, chard, coriander, endive, fennel, kohlrabi, leek, mustard greens, parsley. Nitrate-containing vegetable juice presents a potential risk if stored incorrectly. 2  If the juice gets contaminated by bacteria that can convert nitrate to nitrite, high levels of nitrite could accumulate over time which could potentially be harmful. 3  Nitrate ingestion from dietary sources, such as vegetables, is safe.