Who should avoid magnesium?

Who should avoid magnesium, the short list, each with its reason

Who should avoid magnesium is the first of three avoid questions the variants ask, and the honest list is short, with avoid meaning take only on advice rather than never. Kidney disease, the main entry: impaired excretion lets magnesium accumulate from doses a healthy adult clears, hypermagnesaemia being almost entirely a kidney-disease event, so anyone with chronic kidney disease, reduced kidney function or on dialysis takes magnesium in any form, antacids and laxatives included, only on a doctor's instruction with monitoring. Myasthenia gravis: magnesium reduces acetylcholine release at the neuromuscular junction, where transmission is already impaired in the condition, so supplements and infusions can worsen weakness and the decision belongs to a specialist. Heart block and a very slow pulse: magnesium slows cardiac conduction, the reason it is used intravenously in some arrhythmias and the reason a cardiologist decides for someone with existing conduction disease. Interacting medicines, until a pharmacist sorts them: the tetracyclines, quinolones, bisphosphonates, levothyroxine and gabapentin that are spaced by hours, the proton-pump inhibitors, diuretics and digoxin that change magnesium's picture and need a conversation, none an absolute bar and all a reason to run the cupboard past a pharmacist once. Pregnancy and breastfeeding: requirements change and a midwife or GP decides, as with every supplement here. Under-eighteens, by this site's rule rather than by law: no supplement guidance is given to minors. Bowel obstruction or severe gut disease, where the osmotic effect and the medical picture make a doctor's question. Everyone not on that list is the healthy adult the guidance level was set for, taking magnesium daily within about 400mg supplemental where a diet audit finds intake short.

What to avoid while taking magnesium, why anyone would avoid glycinate, and the triple filed

What to avoid while taking magnesium glycinate, the second avoid question, is four items rather than a diet. A fasted morning medicine's slot: levothyroxine, the bisphosphonates and any fasted antibiotic of the chelating classes are taken alone, and magnesium goes to the evening meal hours away, the empty-stomach page's collision. High-dose zinc: over about 100mg a day zinc reduces magnesium absorption in the balance study, an irrelevance at adequacy doses of 10 to 25mg but a reason not to stack a high-dose zinc on the same meal. Hidden magnesium: antacids and indigestion remedies, magnesium hydroxide laxatives, Epsom salts and a multivitamin's magnesium line all add elemental magnesium toward the 400mg level without announcing it, the not-with page's fourth list. A laxative salt at night: citrate and oxide taken at bedtime deliver their osmotic effect in the small hours, so a nightly habit is bisglycinate, and gram-scale calcium is taken at a different sitting for the reader on high-dose calcium. Ordinary food and ordinary supplements need no avoiding, phytate-heavy meals trimming absorption modestly and creatine, protein, vitamin D, omega-3 and adequacy zinc sitting beside magnesium without a conflict. Why anyone would avoid glycinate, the third avoid question, mostly dissolves: bisglycinate is the best-absorbed and least laxative common salt, the one this section recommends for a nightly habit, and the only reasons to avoid a glycinate product are the ones that apply to any magnesium above plus one that is specific, the oxide-buffered product sold under the glycinate name whose ingredients list reads bisglycinate then oxide and whose elemental figure per capsule is chemically implausible for true glycinate, the budget glycinate page's trap, which is a reason to avoid that product and not the salt. The glycine in bisglycinate is a few hundred milligrams per dose, an amount that gives no one a reason in either direction. The triple filed: a short who, a four-item what, a why that dissolves into one bad product, and the worked example being bisglycinate alone at 300mg elemental for everyone not on the list, £19.99 for 90 days at 22p.

The verdict, a short list, four items, and a salt with no case against it

Who should avoid magnesium: a short list who take it only on advice, anyone with kidney disease, myasthenia gravis, heart block or a very slow pulse, anyone on interacting medicines until a pharmacist sorts them, anyone pregnant or breastfeeding, under-eighteens by this site's rule and anyone with severe gut disease, with what to avoid while taking it being a fasted medicine's slot, high-dose zinc, hidden magnesium in antacids, laxatives and multivitamins and a laxative salt at night, and why avoid glycinate dissolving into one product, the oxide-buffered tub sold under the name. For everyone not on the list: Futuro Labs Magnesium Glycinate, bisglycinate alone, 300mg elemental at 80% NRV, £19.99 for 90 days at 22p a day.

What to check on the label

Questions people also ask

Who should not take magnesium glycinate?

Without medical advice: anyone with kidney disease, where magnesium accumulates; myasthenia gravis, where it can worsen weakness; heart block or a very slow pulse; anyone on interacting medicines until a pharmacist sorts them; anyone pregnant or breastfeeding; and under-eighteens by this site's rule.

What should I avoid when taking magnesium glycinate?

Four things: a fasted morning medicine's slot, since levothyroxine and bisphosphonates are reduced by magnesium; zinc over about 100mg on the same meal; hidden magnesium in antacids, laxatives and multivitamins that double-counts toward 400mg; and citrate or oxide at bedtime.

Why would anyone avoid magnesium glycinate?

For the reasons that apply to any magnesium, the short list above, and for one product-specific reason, an oxide-buffered tub sold under the glycinate name, revealed by oxide in the ingredients list and an implausible elemental figure per capsule; the salt itself is the best tolerated.

Can I eat normally while taking magnesium?

Yes: phytate-heavy meals trim absorption modestly and nothing in ordinary food cancels a dose, and creatine, protein, vitamin D, omega-3 and adequacy zinc sit beside magnesium without conflict.

Is magnesium bisglycinate safe for most adults?

Yes: a healthy adult not on the short list takes it daily within the UK guidance level of about 400mg supplemental where a diet audit finds intake short, the salt being the best absorbed and least laxative of the common forms.

Sources

1. The hypermagnesaemia literature: the kidneys excrete surplus magnesium, so supplementation is safe for healthy adults within guidance and warrants medical advice in chronic kidney disease, where impaired excretion allows magnesium to accumulate. PubMed record
2. The myasthenia gravis and magnesium literature: magnesium reduces acetylcholine release at the neuromuscular junction and can worsen weakness in myasthenia gravis, with magnesium supplements and infusions treated as a caution in that condition. PubMed record
3. The magnesium and medicines literature: magnesium supplements reduce absorption of tetracycline and quinolone antibiotics, bisphosphonates and levothyroxine when taken together and are spaced from them, while proton-pump inhibitors and some diuretics lower magnesium status, a reason for medical advice in either direction. PubMed record
4. The zinc and magnesium interaction literature: very high supplemental zinc, in the region of 140mg a day, reduced magnesium absorption and balance in a metabolic study, while ordinary supplemental doses of 10 to 25mg show no meaningful interaction, and high zinc also depletes copper. PubMed record

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