Choline: Food for Thought

Choline - the word may be vaguely familiar, but you probably don't know much about this nutrient, which shows signs of being quite important to our early development, and all through our lives in our brains, livers, and perhaps much more.

What Is Choline?

Choline is a chemical similar to the B-vitamins, and is often lumped in with them, although it is not (yet) an "official" B-vitamin. Although its entire mechanism of action, particularly how it interacts with other nutrients, is not completely understood, it seems to often work in concert with folate and an amino acid called methionine. Although the human body can make some choline it is generally recognized that it is important to get dietary choline as well.

What are the Benefits of 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. Human milk has high levels of choline.

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 been disappointing). 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. This is an area where more research is needed, but there are some positive first signs.

What are Good Sources of Choline?

Until 2004, when the USDA published a database of choline in foods, we only had scattered studies to go on. This more systematic study has revealed some surprises, notably that there is less choline in many foods than previously thought. Although most foods have at least a little choline, some people may have to pay more close attention to get enough in their diets, particularly if they do not eat many whole eggs. Here are some examples of foods that are particularly high in choline, taken from the USDA’s Database for Choline in Foods.

• Beef liver - pan-fried - 100 grams (about 3.5 oz) - 418 mg
• Whole large egg - 112 mg choline
• Beef (ground) 80% lean/20% fat - 3.5 oz patty - 81 mg
• Cauliflower - 3/4 C cooked (1" pieces) - 62 mg
• Navy beans - 1/2 C cooked - 48 mg
• Tofu - 100 grams (about 3.5 oz) - 28 mg
• Almonds - sliced - 1/2 cup - 26 mg
• Peanut butter - 2 T - 20 mg

For me, one of the important messages of choline (and other recently-discovered nutrients) is that we are still learning so much about nutrition. This emphasizes the importance of eating a variety of whole foods, so we will be less likely to miss out on some yet-to-be-discovered nutrients.

Is it Possible to Get Too Much Choline?

Actually, yes. The Tolerable Upper Intake level for adults has been set at 3.5 grams (3500 mg) per day. Above this, adverse effects can include low blood pressure, diarrhea, and fishy body odor.

How Much Choline Do We Need?

An RDA for choline has not been established, but the National Academy of Sciences recommends the following for "adequate intake" of choline. The information in this table (and much of the information in this article) was taken from Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline by The National Academies Press