Choline
Choline comes in several forms and is common in almost all foods. Commonly it comes in the form of phosphatidylcholine. This nutrient is essential for the production of acetylcholine. Acetylcholine is the neurotransmitter in the brain most commonly associated with memory. The effects of choline supplementation are still inconsistent. It appears to have little or no effect in the short term however longer term supplementation has shown some benefits. Alone, it does not appear to enhance cognition or memory in healthy brains however consistently improves performance in brain with cognition problems such as older brains. It is also more likely to enhance function when combined with other supplements such as vitamin B12, vitamin E or omega 3. Overall supplementation over the long term of choline may be beneficial to maintain normal brain functioning or enhance actions of other brain supplements.
Most beneficial for - underperforming or older brains
Dosage - Difficult to determine but probably at least 100mg/day although closer to 500mg/day is preferred (commonly from lecithin (phosphatidylcholine) or choline bitartrate.
Length of action - between 7-45 days to see effects
Safety - Choline is very safe. It is found in all foods although very high doses (10grams) may cause gastrointestinal side effects.
Type of cognition effected - total cognition but mainly memory
Enhancers - Vitamins B12 and E and omega 3 fatty acids
Supporting Studies
Human serial learning: enhancement with arecholine and choline impairment with scopolamine (Sitaram et al, 1978)
Subjects were given scopolamine to induce cognitive deficits. They were then given 10g of choline supplementation or a placebo. Choline supplementation reversed the cognitive deficits caused by the scopolamine.
Improvement in quality of life in the elderly. Results of a placebo-controlled study on the efficacy and tolerability of lecithin fluid in patients with impaired cognitive functions (Volz et al, 2004)
A double blind placebo controlled study in which 96 patients with mild cognitive impairments were given a lecithin supplement or placebo for 84 days. The group receiving the lecithin showed significant improvemnts in all cognitive parameters measured compared to the placebo group. The study also demonstrated good tolerability to the lecithin supplement.
Enhancement of maze learning in old C57BL/6 mice by dietary lecithin (Golczewski et al, 1982)
Groups of old mice received either lecithin/vitamin e or standard mouse chow. Testing in a maze showed that mice receiving the lecithin/vitamin e performed significantly better than the group receiving the standard chow.
Egg phosphatidylcholine combined with vitamin B12 improved memory impairment following lesioning of nucleus basalis in rats (Masuda et al, 1998)
Rats were given brain lesions to produce memory and cognition impairments. Rats the received either high dose phosphatidylcholine, high dose vitamin b12 or low dose of both. High dose phosphatidylcholine and high dose vitamin b12 did not improve memory acquisition or retention however low doses of both together increased choline levels in the brain and significantly improved memory acquisition and retention.
Administration of phosphatidylcholine increases brain acetylcholine concentration and improves memory in mice with dementia (Shu-ying Chung et al, 1995)
Both mice with and without dementia were administered 100mg of egg derived choline daily for 45 days. Acetylcholine levels increased in both groups of mice brains however only the dementia group of mice showed improvements in memory (passive avoidance tests).
Intakes of Dietary Docosahexaenoic Acid Ethyl Ester and Egg Phosphatidylcholine Improve Maze-Learning Ability in Young and Old Mice (Sun-Young Lim and Suzuki, 2000)
Both old and young mice were given either omega 3 fatty acid, choline, both or a placebo and their ability to learn a maze tested. The groups taking the omega 3/choline supplements learned the maze more rapidly than the controls groups in both young and old mice.
Dietary CDP-choline supplementation prevents memory impairment caused by impoverished environmental conditions in rats (Teather and Wurtman, 2005)
Rats were kept in an impoverished environment to produce memory and cognition problems or an enriched environment that did not produce these effects. Both groups received 500mg/kg per day of a choline supplement for 3 months. At the end of 3 month the choline supplement was shown to reduce the effects of the impoverished environment on cognition and memory but showed no effect on rats in the enriched environment. supplementation shorter than 3 months also showed no effect.
Contradictory Studies
Effect of lecithin on memory in normal adults (Harriss et al, 1983)
A double blind placebo controlled trial with 9 participants. One group took 20g of lecithin while the other a placebo 5 hour before cognitive tests were performed. Although plasma choline levels rose significantly in the lecithin group no improvements were observed in serial learning, paired associate learning or word recognition tasks.
The influence on cognition of the interactions between lecithin, carnitine and carbohydrate (Benton and Donohoe, 2004)
In this double blind placebo controlled study 400 females recieved either lecithin (1.6g/day), carnitine (500mg/day), both or a placebo for 3 days. No improvements in memory or learning were observed by these supplements.