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Brain Development - Choline
Two substances, Lecithin and Choline, recently were elevated to
the status of "essential nutrients" for humans. Lecithin is a special
type of fat, called a phospholipid, and has the chemical name of
phosphatidylcholine. About 13% by weight of the Lecithin molecule is Choline,
but Choline also does appear in free form.
Both Lecithin and Choline are important to human health, according to the Food
and Nutrition Board (a subgroup of the National Academy of Sciences). "A
growing body of research shows Choline is essential to humans", according
to the Board chairman. "However, much of the evidence has accumulated in
the last 10 years, after the Board last completely revised its RDAs in
1989".
This group of US and Canadian scientists has taken the step (April 1998) to
recommend a daily Choline intake of 550 milligrams for adult men and 425
milligrams for adult women. Because of a high requirement for Choline in growing
fetuses and infants, they also recommended intakes of 450 mg and 550 mg by
pregnant and lactating women, respectively.
During the 1970s, the average American diet contained about 6,000 mg of Lecithin
per day. This translated to about 750 to 800 mg of Choline. Today, diet intakes
of these substances are much less because of the trend to cut back on fatty
foods – such as eggs, organ meats, and other meats. These are good sources of
Lecithin/Choline, whereas grains, fruits, and vegetables are poor sources.
Lecithin is abundant in nerve-cell membranes and is necessary for nerve growth
and function. Choline helps generate methyl groups. These are very important in
activating DNA. Choline is also considered very important for the developing
brain in a fetus or an infant.
Both Lecithin and Choline serve other functions in reproduction and development.
In laboratory studies, Lecithin has been shown to nearly double the ability of
sperm to enter and fertilize an egg. Another Choline phospholipid is involved in
implanting the egg in the uterine wall, fetal maturation, and in inducing labor.
("Recommended Daily Intake for Choline and Choline Phospholipids: Should
There be a Dietary Reference Intake for Choline?"; King, J.C.; AOCS annual
meeting, Indianapolis, Indiana; May 1996.) |