Choline the newest official member of the B vitamin family, had its Adequate Intake levels (AIs) established for the first time by the National Academy of Sciences in 1998. Even though it has only recently been adopted into the official family of vitamins, choline has been the subject of nutritional investigations for almost 150 years.

Key research discoveries about choline came in the late 1930s, when scientists discovered that tissue from the pancreas contained a substance that could help prevent fatty build-up in the liver. This substance was named choline after the Greek word chole, which means bile. Since the 1930s, research has shown that choline is found not only in the pancreas and liver, but is also, in fact, a component of every human cell.
Research has also shown that the naming of choline after the Greek word for bile was highly appropriate. Bile, which is made in our liver, has the primary job of making fat compatible with water, so that fat-based substances can get transported around the body in the water-based world of our blood. Choline has very similar fat-modifying effects in the membranes of our cells. The fat-modifying properties of choline allow our cell membranes to operate with greater flexibility in handling both water- and fat-soluble molecules. Without choline, many fat-based nutrients and waste products could not pass in and out of our cells.
In addition to its uniqueness as a fat-modifying substance, choline is chemically unique as a trimethylated molecule. The term methylated means that a substance has at least one special chemical group - called a methyl group - attached to it. Choline is trimethylated, meaning three methyl groups are attached. Many important chemical events in the body are made possible by the transfer of methyl groups from place to place. Genes in the body can be turned on and turned off in this way, and cells often use this same process to send messages back and forth. In the area of mental health, where messages sent from nerve to nerve are especially critical, choline has turned out to be a substance of great interest. (Source: www.whfoods.org)

What is Choline?

Choline serves various functions in our bodies – in the structure of cell membranes, protecting our livers from accumulating fat, as the precursor molecule for the neurotransmitter acetylcholine, and more. Because of rapid development in fetuses and infants, we have a great need for choline in our early lives.

Choline started to get the interest of nutrition researchers when it was found that fetal rats whose mothers didn't get enough choline in their diets had less brain development and poorer memories after birth than those whose mothers ate adequate amounts of the nutrient. Over the past few years, there has been a rush of research, and there are now hints that choline may be essential not only for the brain development of fetuses and infants, but may help prevent memory loss associated with aging (although attempts to reverse cognitive decline have not been encouraging). Choline has been shown to protect the liver from certain types of damage, and can help reverse damage that has already occurred. Additionally, it may help lower cholesterol and homocysteine levels associated with cardiovascular disease, and may also help protect against some types of cancers.

Possible Side-Effects / Precautions / Possible Interactions
Choline is likely safe for most adults and children when used appropriately.
High doses are possibly unsafe for adults and children. Doses over the Daily Upper Intake Levels (see dosage section below) are more likely to cause side effects such as sweating, a fishy body odor, gastrointestinal distress, diarrhea, and vomiting.
There is some concern that increasing dietary choline intake might increase the risk of cancer of the colon and rectum. One study found that women eating a diet that contains a lot of choline have an increased the risk of colon cancer. However, more research is still needed to determine the effects of diet on colon cancer.

Special Precautions & Warnings
Pregnancy and breast-feeding: Choline is LIKELY SAFE when taken by mouth and used appropriately. Doses up to 3 grams daily for pregnant and breast-feeding women up to 18 years of age, and 3.5 grams daily for women 19 years and older are not likely to cause unwanted side-effects. There isn’t enough information available about the safety of choline used in higher doses in pregnant or lactating women. It’s best to stick to recommended doses.

Research Studies / References
http://www.news-medical.net/news/20100105/New-study-reveals-choline-plays-a-critical-role-in-fetal-brain-development.aspx
Natural Health: Choline is a precursor to the neurotransmitter acetylcholine, essential for memory and cognition. Also, it is a phospholipid that helps promote neuronal membrane fluidity, which is important for communication between brain cells. One form of this fat, phosphatidyl choline, is the active ingredient in lecithin--an emulsifier commonly found in processed foods, and derived from either soy or animal sources. In the brain, phosphatidyl choline also plays a role in repairing and maintaining neurons. According to Khalsa, most people ingest about 1,000 mg of lecithin every day as part of a normal diet, but that amount is not sufficient to promote optimal brain function throughout life.
Choline, in its various forms, is widely reputed to enhance cognition and memory not only in people with mild memory impairment, but in normal healthy people as well.

Many studies have been conducted on choline. In one early clinical study published in the journal Science in 1978, subjects demonstrated improved performance on intelligence and memory tests after ingesting choline.