Is collagen good for your nervous system?

The register's nervous system sentence and its eleven holders, and the one on a collagen label

Is collagen good for your nervous system is a question usually prompted by a tub that lists nerve health or mood among its benefits, and the honest page answers it by opening the UK nutrition and health claims register at the nervous system sentence and reading who is allowed to hold it, because the register is the list of what the evidence has earned and a tub's benefit list is the list of what the marketing wants. The sentence is contributes to normal functioning of the nervous system, and it is authorised for eleven nutrients: thiamine, riboflavin, niacin, vitamin B6, biotin and vitamin B12 among the B vitamins, vitamin C, magnesium, copper, iodine and potassium. A related sentence, contributes to normal psychological function, is held by thiamine, niacin, vitamin B6, vitamin B12, folate, biotin, vitamin C and magnesium, and a third, contributes to the reduction of tiredness and fatigue, by several of the same. Each of those sentences rests on deficiency evidence, what goes wrong in a nervous system short of the nutrient: without thiamine the nerves and the brain fail in beriberi and Wernicke's syndrome; without B12 the spinal cord's myelin degenerates and the feet tingle and go numb; without niacin the brain fails in pellagra; without iodine the thyroid cannot supply the hormone the developing brain needs; and so on through the list, each a nutrient the nervous system cannot work without and each met from an ordinary varied diet in a fed adult, with B12 the one worth testing in vegans and older adults and vitamin D, not on this list, the one worth taking through a UK winter for other reasons. Collagen holds neither sentence. Nor does glycine, nor gelatin, nor any protein hydrolysate, nor protein itself, whose sentences are about muscle and bone; the register has assessed nothing that would let a collagen tub say anything about nerves, mood or the mind, and a tub that does is printing a sentence it does not hold. The only thing in a collagen capsule that may carry the nervous system sentence is the vitamin C beside it, if the dose reaches the threshold for a claim, which the worked example's 15% of the reference value does, so that an honest collagen capsule may say that its vitamin C contributes to normal functioning of the nervous system and may not say that its collagen does, and a reader who sees nerve health on a collagen label should look for which ingredient is carrying it and at what dose.

Collagen in the nervous system, collagen for the nervous system, and the one active component

Collagen's own relationship to the nervous system is two-sided, and the honest page gives both sides because the tub blurs them. The first side is collagen in the nervous system. Peripheral nerves are wrapped in connective tissue sheaths, the endoneurium, perineurium and epineurium, built of type I and type III collagen, which protect the nerve fibres and carry the blood vessels that feed them; the basement membranes beneath the cells of the blood-brain barrier and around the brain's small vessels are built of type IV collagen; and the spinal cord and brain are surrounded by the meninges, collagen-rich membranes. All of that collagen is made on site, by fibroblasts and related cells, from the body's amino acid pool, under the cells' own signals, whatever is or is not eaten, so that eating collagen does not deliver collagen to a nerve any more than eating muscle delivers muscle, and a fed adult's nerve sheaths are maintained from the same pool a steak or a scoop of whey feeds. The second side is collagen for the nervous system, and here collagen the supplement has one component with a nervous system action, glycine, and one notable absence, tryptophan. Glycine is around a third of collagen's amino acids and is itself an inhibitory neurotransmitter in the brainstem and spinal cord and a co-agonist at the brain's NMDA receptors, so it is not inert to the nervous system; small randomised trials of around three grams of glycine taken before bed reported better subjective sleep quality, a shorter time to fall asleep and better next-day alertness, with a proposed mechanism through a small fall in core body temperature, which is the one place a reader taking a 10 to 15g scoop of collagen in the evening, supplying three to five grams of glycine, has a plausible nervous system effect to feel, and which a two-capsule 1200mg habit, supplying around 400mg, does not reach. Beyond sleep, there is no randomised trial of glycine or collagen for anxiety, mood, cognition, memory, nerve pain or nerve regeneration in humans, only animal work and mechanism, and no claim. The absence is tryptophan: collagen contains none, which is why it is an incomplete protein and why a tryptophan-free amino acid load taken as the sole protein lowers brain tryptophan and serotonin synthesis in laboratory depletion studies, an effect that does not occur when collagen is a dose within a complete-protein diet and that the trials show no sign of, but which is a reason not to make collagen the main protein of a day. So collagen is good for the nervous system in the way any protein is, by contributing amino acids to the pool the nervous system's own tissues are built from, has one active component whose evidence is sleep at scoop doses, and holds no sentence; the B vitamins, magnesium, iodine and potassium on the register's list are met from food and tested for by a doctor when tingling, numbness or persistent fatigue suggest a deficiency. The worked example is the holder of the sentence on the label, stated on its true terms: two capsules, 1200mg hydrolysed type 1 marine collagen with 12mg vitamin C at 15% of its reference value plus zinc, 120 for £16.99 at 28p a day, lab tested and UK made, the vitamin C carrying its nervous system and psychological function sentences, the collagen holding none, around 400mg of glycine and below the 2.5 to 15g research band. Is collagen good for your nervous system: as protein, yes, as a nerve supplement, no sentence and one sleep-sized component, and the nerve health on the label is the vitamin C's.

What to check on the label