Some experts say that a fact is common knowledge if it can be found in three independent sources. Purdueâs Online Writing Lab recommends finding five independent sources before considering a fact common knowledge. The point is that common knowledge can be found in a variety of sources.
VITAMIN D. Vitamin D and vitamin A are the most toxic of the fat-soluble vitamins. The symptoms of vitamin D toxicity are nausea, vomiting, pain in the joints, and loss of appetite. The patient may experience constipation alternating with diarrhea, or have tingling sensations in the mouth.
The Dangers of Vitamin Megadoses. Some vitamins are toxic when taken in the very large amounts known as megadoses. Itâs nearly impossible for your diet to provide an overdose of vitamins D, E, K, C, and all the Bs. Vitamin A is the lone exception.Liver and fish liver oils are concentrated sources of preformed vitamin A (retinol).Liver contains so much retinol that early 20th century explorers to the South Pole made themselves sick on seal and whale liver.itamin A is the lone exception. Liver and fish liver oils are concentrated sources of preformed vitamin A (retinol). Liver contains so much retinol that early 20th century explorers to the South Pole made themselves sick on seal and whale liver.