Choline is a nutrient found in many food sources, including milk, liver, eggs, peanuts, soybeans, beef, cauliflower, kale, and cabbage. It is used in the body for two main purposes, as a precursor to the neurotransmittor acetylcholine and to form lecithin. Although not yet considered an essential nutrient in humans, deficiency may result in liver disease (1), and an adequate intake has been set at 550 mg per day (with an upper limit of 3,500 mg per day). Various conditions, such as stress (including exercise), aging, and certain supplements (such as carnitine and some nootropics) may increase choline need. This article will examine the application of three different types of choline supplements, choline (as bitartate, citrate, chloride, etc.), phosphatidylcholine, and alpha-glycerylphosphorylcholine (alpha-GPC).

Choline

Choline is available in many forms, including choline bitartrate, choline citrate, and choline chloride. Of all of the forms of choline supplements, these are the least effective. Choline supplements have not been researched in many areas (phosphatidylcholine, which is more effective, is generally preferred), but they do not appear to effect cognition or physical performance in healthy individuals after exhaustive activity (2). Large doses of choline administered to rats were rapidly metabolized, implying that the body has a strong adaptive response (3). Additionally, acute dosing of large amounts of choline bitartrate does not change the amount of choline or its metabolites in the human brain (4). Choline supplements are primarily useful where choline levels are low and it becomes the rate limiting factor for phospholipid and acetylcholine synthesis, such as neurodegeneration (5).

Although choline does not appear to be effective for much, it may aid in weight loss, expecially when combined with carnitine. Supplemental choline aids in the conservation of carnitine, increasing its effectiveness (6), and it should also be noted that choline requirements may not be met in periods of caloric restriction. 700 mg of carnitine combined with 1000 mg of choline has been found to reduce bodyfat more than either supplement alone (6). The combination of choline and carnitine along with caffeine causes significant body fat reduction in rats, and exerts a physiological response similar to that of exercise (7).

Lecithin (Phosphatidylcholine)

Lecithin, which contains phosphatidylcholine, has all the beneficial effects of choline, but is both more bioavailable and less expensive. It also has more promising studies supporting supplementation. In humans, choline chloride (2-3 g) raises serum choline by 86% and values return to normal within 4 hours, whereas lecithin increases levels by 265% and choline levels stay above normal for 12 hours (8). After long-term administration, the amount of choline in the blood returns to normal, but phosphatidylcholine remains elevated in certain areas, such as the cortex and striatum (9). Although lecithin supplementation does not effect acetylcholine levels under normal conditions, it facilitates its release in times where there is elevated need for acetylcholine (10). This includes periods of stress – in a study where rats were subjected to C-H-R (cold-hypoxia-restraint), a test that measures adaptation and resistance to stress, lecithin increased both tolerance and recovery (11).

Exercise is another activity that increases both mental and physical stress. Exercise causes a significant depletion of choline levels, and it has been hypothesized that this may impair performance (12). Unfortunately, lecithin has not yet been shown to increase athletic performance, although it does prevent the decline in choline seen with exercise (13).

Long term use of lecithin may aid in the prevention of neurological degeneration. Combined with pyruvate, it slowed nerve degeneration in mice (14). Studies in senile mice also indicate improved memory, increased acetylcholine, and improved learning (combined with B12) (15, 16).

Alpha-GPC

Alpha-glycerylphosphorylcholine is the most bioavailable form of choline, and also has some mild nootropic effects. It improves performance in both active and conditioning tasks in both young and old mice by increasing production of inositol phosphate (17), as well as increasing protein kinase C activity (an effect of other nootropics, such as oxiracetam) (18), acetylcholine release (18), and nerve growth factor (19). It has been effectively used to treat Alzheimer's and increase recovery from stroke, and it also increases GH in both young and old humans (20).

The only problem with alpha-GPC at present is the cost. One gram a day is the recommended dosage, which will be cost-prohibitive for most people. However, any dosage will impart benefits, so a low dose of alpha-GPC combined with lecithin is cost-effective. Pinnacle AlphaDopa employs a sublingual delivery system for alpha-GPC, which may also improve the effectiveness of a given amount.

If you have any questions or comments regarding this article, please email dvdtlsn@bulknutrition.com.


No part of this article may be reproduced in any form without the permission of David Tolson or Mike McCandless.