Choline
Choline is an organic compound, classified as a water-soluble essential nutrient and usually grouped within the Vitamin B complex. This natural amine is found in the lipids that make up cell membranes and in the neurotransmitter acetylcholine. Adequate intakes (AI) for this micronutrient of between 425 to 550 milligrams daily, for adults, have been established by the Food and Nutrition Board of the Institute of the National Academy of Sciences. of Medicine
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Choline as a Supplement
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It is well established that supplements of methyl group transfer vitamins B6, B12, and folic acid reduce the blood titer of homocysteine and prevent heart diease. Choline is a necessary source of methyl groups for methyl group transfer. Supplements of lecithi/choline by Central Soya scientists reduced heart disease in laboratory studies. The reduction in heart disease with lecithin supplements may however relate more to the cholesterol carrying capacity of lecithin than to the methyl group transfer role of choline.
Choline supplements are often taken as a form of 'smart drug' or nootropic, due to the role that the neurotransmitter acetylcholine plays in various cognition systems within the brain. Choline is a chemical precursor or "building block" needed to produce the neurotransmitter acetylcholine, and research suggests that memory, intelligence and mood are mediated at least in part by acetylcholine metabolism in the brain. The compound's quaternary amine renders its lipid insoluble which might suggest it would be unable to cross the blood-brain barrier. However, despite choline's lipid insolubility, a choline transporter exists that allows transport across the blood-brain barrier. The efficacy of these supplements in enhancing cognitive abilities is a topic of continuing debate.
Lakhan & Vieira (2008) link choline deficiency to bipolar disorder and report efficacy in lecithin supplementation based on a double-blind, placebo controlled trial.
Some people who practice lucid dreaming use Galantamine with choline bitartrate or Alpha GPC to increase their odds of having a lucid dream. Acetylcholine precursors such as choline work synergistically with Galantamine to help improve memory and the symptoms of Alzheimer's Disease (AD).
The Food and Drug Administration (FDA) requires that infant formula not made from cow's milk be supplemented with choline.
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Disease Prevention
- Cardiovascular diseases: A large body of research indicates that even moderately elevated levels of homocysteine in the blood increase the risk of cardiovascular diseases. Choline, when oxidized in the body to form betaine, provides a methyl group for the conversion of homocysteine to methionine by the enzyme, betaine-homocysteine methyltransferase (BHMT). Despite its relevance, the relationship of betaine and choline to homocysteine metabolism has been only lightly investigated in humans. Methodological problems make betaine and BHMT difficult to measure. One study found higher urinary excretion of betaine and its metabolites in patients with vascular disease and elevated homocysteine levels compared to control subjects, suggesting that elevated blood homocysteine levels were not related to reduced intake of choline or betaine or diminished activity of BHMT. In preliminary studies, pharmacologic doses of betaine (1.7 to 6 grams/day) were found to reduce blood levels of homocysteine in a small number of patients with vascular disease and elevated homocysteine levels. Additionally, a small study in 26 healthy men reported that choline supplementation decreased plasma homocysteine concentrations. However, a prospective cohort study in 14,430 middle-aged men and women participating in the Atherosclerosis Risk in Communities study found that dietary choline or dietary choline and dietary betaine, together, was not associated with coronary heart disease. Although further research is indicated, convincing evidence that increased dietary intake or blood levels of choline or betaine affect homocysteine levels and cardiovascular disease risk in humans is presently lacking.
- Cancer: In rats, dietary choline deficiency is associated with an increased incidence of spontaneous liver cancer and increased sensitivity tocarcinogenic chemicals. A number of mechanisms have been proposed to explain the cancer-promoting effects of choline deficiency: (a) choline deficiency causes liver damage and regenerating liver cells are more sensitive to the effects of carcinogenic chemicals; (b) choline deficiency results in decreased methylation of DNA, resulting in abnormal DNA repair; (c) choline deficiency results in increased oxidative stress in the liver, increasing the likelihood of DNA damage; (d) choline deficiency may stimulate changes in the programmed cell death (apoptosis) of liver cells, contributing to the development of liver cancer; and (e) choline deficiency activates the potent cell-signalling molecule, protein kinase C, which creates a cascade of effects that are still being investigated. The implications for choline deficiency on human susceptibility to cancer remain unclear.
Pregnancy Complications
- Neural Tube Defects :It is known that folate is critical for normal embryonic development, and maternal supplementation with folic acid decreases the incidence of neural tube defects (NTD). NTD result in either anencephaly or spina bifida, which are devastating and sometimes fatal birth defects. These defects occur between the 21st and 27th days after conception, a time when many women do not realize that they are pregnant. While folate's protective effect against NTD is well recognized, the effects of other methyl group donors, including choline and betaine, are not known. A recent case-control study (424 NTD cases and 440 controls) found that women in the highest quartiles of choline and betaine intake, in combination, had a 72% lower risk of a NTD-affected pregnancy. More research is needed to determine whether choline is involved in the etiology of NTD.
- Cognitive functioning (memory): Increased dietary intake of choline very early in life can diminish the severity of memory deficits in aged rats. Choline supplementation of the mothers of unborn rats, as well as rat pups during the first month of life, leads to improved performance in spatial memory tests months after choline supplementation has been discontinued. A recent review by McCann et al. discusses the experimental evidence from rodent studies regarding the availability of choline during prenatal development and cognitive function in the offspring. It is not clear whether findings in rodent studies are applicable to humans. More research is needed to determine the role of choline in the developing brain and whether choline intake is useful in the prevention of memory loss or dementia in humans.
Disease Treatment
- Dementia (Alzheimer's disease): Alzheimer's disease has been associated with a deficit of the neurotransmitter, acetylcholine, in the brain. One possible cause for the acetylcholine deficit is a decrease in the expression of an enzyme that converts choline into acetylcholine in the brain. Large doses of lecithin (phosphatidylcholine) have been used to treat patients with dementia associated with Alzheimer's disease in hope of raising the amount of acetylcholine available in the brain. However, a systematic review of the randomized trials did not find lecithin to be more beneficial than a placebo in the treatment of patients with dementia or cognitive impairment.
Other Sources of Choline
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The foods richest in phosphatidylcholine — the major delivery form of choline — are egg yolks, soy and cooked beef, chicken, veal and turkey livers. Many foods contain trace amounts of free choline, even iceberg lettuce. To what extent these trace forms are usable by human digestion is still debated. In 2004, the USDA released its first database of the choline content in common foods.
The most often available choline dietary supplement is lecithin, derived from soy or egg yolks, often used as a food additive. Phosphatidylcholine is also available as a supplement, in pill or powder form. Supplementary choline is also available as choline chloride, which comes as a liquid due to its hydrophilic properties. Choline chloride is sometimes preferred as a supplement because phosphatidylcholine can have gastrointestinal side effects.
Although the human body can make some choline it is generally recognized that it is important to get dietary choline as well. 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
Choline is found in the following products:
ANDRO-VITO
APHRO-VITA
APHRO 40+
EREXUS
LIBIDO-VITA
LOVE FIRE
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