Magnesium is an essential mineral that helps the body maintain nerve, muscle and cardiovascular activity. Among the forms of magnesium, magnesium citrate is preferred because it is easier to absorb than many other forms of inorganic. However, the duration of this compound's existence in the body is not fixed, depending on many physiological factors and personal habits.
Health status and type of Magnesium used
According to Dr. patricia Mikula, clinical pharmaologist at the University of Minnesota (USA): "The body of people with magnesium deficiency tends to retain more magnesium, while people with normal magnesium levels will excrete it faster". Therefore, people with magnesium deficiency will see the effects of magnesium citrate last longer.
In addition, magnesium also plays an important role. Magnesium citrate (organic form) is better absorbed than magnesium oxide (inorganic form). However, if you use magnesium citrate in its solution to treat constipation, the main effect is to soften stools, not to supplement magnesium for the body.
In addition, digestive diseases such as inflammation, Crohn's disease or Celiac disease can reduce the ability to absorb magnesium, causing less magnesium to be retained in the body. People with kidney disease experience the opposite situation, magnesium is difficult to excrete, and there is a risk of accumulation causing poisoning.
Doses, medications, and foods affect absorption
Taking too high a magnesium dose does not help increase absorption. In contrast, according to the American Academy of Nutritional Medicine, the body absorbs up to 65% magnesium when taking a small dose of 36mg/day but only absorbs 11% when taking a large dose of 900mg/day. The maximum dosage from supplements should be below 350mg per day to avoid diarrhea, nausea and abdominal pain.
Some drugs that can reduce or increase magnesium excretion: diuretic drugs, antibiotics (such as amoxicillin, ciprofloxacin), blood pressure drugs, corticoids, estrogen or anti-concussion drugs. People who are taking these drugs should consult a doctor before supplementing magnesium citrate.
Food can also interfere with absorption. Foods containing oxalate ( duck feet, kale), phytate ( greens, whole wheat bread) and unfermented fiber reduce magnesium absorption. Meanwhile, alcohol, caffeine and foods high in sodium cause magnesium to be excreted faster through the kidneys.
Age and other supplements also determine the effectiveness
As we age, the intestines' ability to absorb magnesium decreases and the kidneys excrete more, making it easier for the elderly to be magnesium deficient even if they eat well. In addition, the simultaneous use of calcium, zinc, iron or manganese in high doses can hinder magnesium absorption.
According to Dr. Mikula: "Old people, people with chronic diseases or taking medication should supplement magnesium according to the instructions of a pharmaceutical or doctor to avoid excess or deficiency".
The body absorbs magnesium very quickly, after only 1 hour of taking it, the small intestine begins to absorb it, and after 6 hours it has reached 80%. About 50% of magnesium is stored in bones, the rest in muscles and soft tissue. Excess magnesium is excreted in urine.
In the US, functional foods such as magnesium citrate are not as strictly controlled as prescription drugs. Therefore, consumers should choose products certified by NSF, US Pharmaceutical Company (USP) or ConsumerLab to ensure accurate quality and dosage.
If you want to supplement magnesium safely and effectively, consult a health professional, especially if you have an underlying disease, are pregnant or take long-term medication.
