A Neuron’s Best Friend
If you wrote up a list of the brain processes that require vitamin C to function, it would include just about everything the brain has to do to keep your memory intact and your daily life on track. Vitamin C plays a key role in –- Making new neurons from stem cells – processes called neuronal differentiation and maturation.
- Coating neurons with the myelin sheaths that protect them and help transmit information to the brain’s neural networks.
- Regulating the system of nerve cells (called the cholinergic system) that reinforces your memory and helps you learn new knowledge.
- Supporting the brain’s glutaminergic system – the neuronal system that’s central for retrieving memories.
Peeking Through the Blood/Brain Barrier
The brain is able to stubbornly hold on to its supply of vitamin C because the blood/brain barrier enables vitamin C to enter brain tissue from the blood but, when the barrier is working correctly, it keeps vitamin C from leaving.3 Once it’s in the brain, vitamin C stays busy offering antioxidant protection for neurons as well as taking part in the processes that keep the neurons working properly. Now, although studies have not found that giving doses of vitamin C to people who already have Alzheimer’s is any help, researchers do know that vitamin C performs tasks that are appropriate for helping prevent Alzheimer’s –- It chelates and captures the minerals copper, iron and zinc which could otherwise bind to the amyloid plaque that accumulates when you develop Alzheimer’s. Left to their own devices, these minerals can also lead to the formation of harmful substances called advanced glycation end products (AGEs).4Sidebar comment: Few people need to supplement with iron and copper and you should take these minerals in pill form only if confirmed by a blood test and an expert nutritionist. Most people DO need to supplement with zinc, but, again, it’s best to do it under the guidance of an expert. And the amount you need is usually small – 25 mg a day is adequate for most people. Meanwhile, taking vitamin C will help ensure your body doesn’t accumulate too much of these minerals.
- Vitamin C’s antioxidant activity reduces the development of lesions in the brain that can cause neurons to malfunction.5
- It helps limit inflammation in the brain.6
How Much do You Need?
When it comes to the question of how much vitamin C you need for optimal brain function, the jury is still out. A New Zealand study of brain health in 50-year-olds showed that getting around 110 mg a day of vitamin C didn’t seem to be enough to insure an adequate level in the body.8 The recommended daily amount in the US is 90 mg for men and 75 mg for women,9 which is obviously too low to keep your brain well-supplied. And while the Federal Office of Dietary Supplements says you shouldn’t take more than 2,000 mg a day, few people who really know anything about nutrition would agree. There seems to be little – if any – evidence that taking much, much more than that will do you any harm. The only bad side effect I’ve ever heard from vitamin C is some gastrointestinal distress. Apparently diarrhea sets in for most people if they take around 10 grams (10,000 mg) a day by mouth. People take much greater amounts than that by IV – bypassing the GI tract problem – and in fact this is a powerful cancer treatment. For the record, I take 2,000 mg per day in supplement form, plus whatever I’m getting in the food I eat, which is probably pretty large.- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5622720/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5622720/
- https://dm5migu4zj3pb.cloudfront.net/manuscripts/119000/119832/cache/119832.1-20140626150553-covered-253bed37ca4c1ab43d105aefdf7b5536.pdf
- https://www.ncbi.nlm.nih.gov/pubmed/20730621/
- https://www.ncbi.nlm.nih.gov/pubmed/22888398/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3725125/
- https://www.ncbi.nlm.nih.gov/pubmed/12076218/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5579624/
- https://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/