Acetylcholine (ACh) is one of the most abundant neurotransmitters in the body, and also one of the most important for healthy brain function. If you've ever experienced "brain fog" it may have been the result of low levels of acetylcholine.
Impairments to learning and memory are just some of the common side effects of inadequate acetylcholine, but if we don't get enough of the raw building block of this neurotransmitter -- choline -- then more serious problems are likely to arise.
Choline and Acetylcholine
Acetylcholine is composed of two substances: choline, which comes from foods like fish, meat, nuts and eggs, and Acetyl-CoA, which is produced in the nerve cells. Choline, which is in the same class as B-vitamins, was recognized as an essential nutrient in 1998 by the Institute of Medicine. 
Choline is required for the body to make acetylcholine, which helps our body:
- Regulate the heart rate
- Improve cell signaling
- Support DNA and cell structure formation
- Ensure proper neural processing
- Prevent cognitive and memory decline
- Keep muscles functioning
How do you become deficient in acetylcholine?
It is generally assumed that we get less choline in our diets than we actually need. Because we make ACh from choline, when we’re deficient in choline, we run the risk of an acetylcholine deficiency.
Choline also plays a role in the metabolism of folate and B12, so when we’re deficient in choline, we may also be lacking in other essential vitamins required to keep our brains and bodies in optimal health. This is especially the case for pregnant women, since such nutrients are directly related to fetal brain development. 
Genetics, sex, and life stage may also play a role in choline absorption, the amount of choline we require, and even the way our bodies use choline. For instance, postmenopausal women are more likely to experience organ problems because of a choline-deficiency than women in their childbearing years. Researchers believe that this is tied to the fact that estrogen is involved in the choline synthesis process. 
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How does an acetylcholine deficiency affect us?
When this important neurotransmitter is in relatively short supply, it can have a range of effects on our cholinergic systems---that is, any of the systems that require acetylcholine to function, including (but not limited to) the brain and nervous system.
Because ACh plays such a huge role in learning and memory, a deficiency may result in
- Poor concentration
- Memory problems
Collectively, these symptoms are often called "brain fog", and as far as the rest of our body is concerned, a lack of ACh can lead to increased heart rate, nerve cell damage, muscle aches, and weakness.
Out of the 3 phases of memory functioning---creating the memory, long-term memory and memory recall---ACh is the most closely related to memory formation and encoding. This usually pertains to the short-term, day-to-day type of learning. Research shows that ACh production is directly related to our short-term memory making and recall, and a lack of it has been linked to Alzheimer’s disease.  Fetal neural tube defects, such as spina bifida and anencephaly, have also been linked to choline deficiencies. 
It is known that the brain is essentially able to regenerate and repair itself over a person’s lifetime, a process called neuroplasticity. This means that after addiction or injury, for instance, the brain may be able to repair itself and come back to optimal functioning. Research shows that ACh can facilitate this process and thus, when we’re lacking ACh, we may not be as capable of regaining brain function after it has been damaged, something that also occurs naturally with age. 
When we don’t get enough choline, we run the risk of getting hyperhomocysteinemia, a blood condition which is associated with cardiovascular disease, Alzheimer’s, Schizophrenia, and osteoporosis.  The most common and well-known effects of a choline deficiency are fatty liver disease and kidney problems.
How can choline supplements help?
Researchers haven't figured exactly how much our choline intake can affect ACh production in the body, but we do know that a choline-rich diet improves cognitive functioning.
One study of 1400 middle-aged and older adults showed that adults who took more choline did better on memory tests. In brain scans, that group also showed less “white-matter hyperintensity” in their brains, areas which are associated with greater risk of stroke and dementia.  Choline supplements may help in the prevention and/or treatment of of liver diseases, Alzheimer’s disease, dementia, behavior disease, certain types of seizures, and Schizophrenia.
Choline Supplement Dosage
According to the U.S. Department of Health, the recommended daily intake of choline is 425-550 mg / day, yet more than 90% of the population fails to achieve this intake.
If you’re taking a new supplement, always be sure to read the instructions carefully, and talk with a healthcare professional if you are taking any other medications. Individual health situations may determine whether or not regularly consuming a particular supplement is right for you. Find out and get on the right track toward better health, starting today!