Everyone from dieticians to Tony the Tiger to our moms have told us that eating a good breakfast is the best way to ensure a positive start to the day. Turns out, one of the nutrients your body needs, vitamin K, is found in two items that are usually a little lower on the list of nutritious breakfast foods: bacon and coffee. If you prefer tea with your morning meal, vitamin K can be found in green tea as well. It's also in cheese and liver. That doesn't mean you shouldn't eat your vegetables, too, it's also found in leafy vegetables, broccoli, and asparagus. Vitamin K is also produced in the intestines.

Vitamin K is a fat soluble vitamin, which means that toxicity may be an issue if you take it in high doses. This is unlikely through food sources, but can occur if you take a supplement with K3, a synthetic form of vitamin K known as menadione. Short term symptoms of vitamin K toxicity are sweating and flushing. Over time, jaundice or anemia can occur. Even though vitamin K is fat soluble though, the body does not store as much of it as it does other vitamins, and you have to make sure that you take enough in consistently. While the body doesn't store much vitamin K, it does use it quite efficiently, recycling it and using it for the same process more than once.

Vitamin K plays a large role in blood clotting, in fact blood cannot clot without it, and symptoms of vitamin K deficiency include frequent nosebleeds and bruises that heal slowly. If you are taking large doses of vitamin A or vitamin E, these can interfere with the body's ability to absorb vitamin K. Because vitamin K facilitates clotting, people who have had problems with blood clots, such as heart attacks or strokes, need to be careful about how much vitamin K they get in their diet, especially if they are on the blood thinning medication coumadin (the generic name for this medication is warfarin). They should still make sure they get the recommended daily allowance (RDA) to avoid other bleeding problems, but should watch consumption levels of foods high in vitamin K, as it can reduce the effectiveness of their medication. Some research has indicated that vitamin K also helps maintain bone strength, especially in older people.