Magnesium FAQs

There is no single "best" magnesium for everyone. Each form has different characteristics and is suited to different needs.

• Magnesium citrate: It can accumulate in muscle and is well absorbed if there is sufficient gastric acid. In people with low stomach acid (the elderly, or those taking gastric protectors) or when taken between meals, absorption may be reduced. The unabsorbed magnesium draws water into the intestine, hence its occasional laxative effect.
• Magnesium bisglycinate: the ultimate all-rounder: well absorbed, well tolerated by the digestive system, and suitable for most people. A safe bet when looking for balanced magnesium supplementation.
• Magnesium threonate: actively crosses the blood-brain barrier, therefore accumulating more in the brain. Its role in concentration, memory, mood, and sleep is being investigated.

👉 In summary: the choice depends on individual need (digestive, muscular or cognitive), not on one form being universally superior.

The best time is whenever you remember to take it , because consistency is more important than the time (the best is the enemy of the good).

If a general recommendation has to be given:

• In the morning , with breakfast or before, depending on the form of magnesium, as some are better absorbed with food and others on an empty stomach. Taking it at this time can provide energy and promote regularity.
• At night , some people notice a greater effect on muscle relaxation and rest .

👉 The key is to integrate it into your daily routine in a practical and sustainable way.

Magnesium is involved in more than 300 bodily reactions, including those that regulate muscle and nerve function. Therefore, it can have different effects depending on its form and the individual.

• Sleep and anxiety → promotes nervous system balance and muscle relaxation. Many people notice improved sleep or reduced tension, especially with forms like bisglycinate or threonate .
• Constipation → taking magnesium is not the best way to address it. Some inorganic salts, such as oxide, chloride, or carbonate , are not well absorbed and can have a laxative effect. Magnesium citrate , taken between meals or by people with hypochlorhydria , can also produce this effect, although it should not be its primary indication.

👉 In summary: magnesium can help with rest and nervousness. Its use for constipation is secondary and limited to certain cases ; it's not the most recommended strategy.

During menopause, it is common to experience changes related to bone, muscle, and emotional health , as well as a tendency towards hypochlorhydria (less stomach acidity), which can hinder the absorption of some forms of magnesium.

• Magnesium bisglycinate is usually the best option because it is well absorbed even with low gastric acidity, is gentle on the stomach, and supports both muscle function and nerve regulation (stress, insomnia, irritability).
• Magnesium threonate may be of interest when the main symptoms are in the cognitive and rest sphere: memory, concentration or sleep quality.

👉 In summary: in menopause, bisglycinate is the most recommended base, and threonate can be a complement depending on individual needs.

Conventional tests measure magnesium in blood serum , but this only represents a small portion of the total. Most magnesium is found in bones, muscles, and tissues .

This means that a "normal" value in the blood test does not guarantee that there is enough magnesium in the body. Conversely, if the serum level is already low, the deficiency is probably more widespread and we are detecting it too late.

Therefore, in addition to analysis, it's often most helpful to assess symptoms and lifestyle : fatigue, cramps, muscle tension, insomnia, chronic stress, or a diet low in magnesium-rich foods. In these cases, supplementation can be a practical tool, always as a complement to a balanced diet.

The Nutrient Reference Value (NRV) for magnesium in adults is 375 mg per day . This is the average amount we need to obtain through our diet to maintain good health.

In supplements, the maximum authorized dose for most forms of magnesium is 250 mg per day . This is due to safety criteria to avoid digestive discomfort, and also because the rest must come from daily food intake .

It's important to remember that, due to soil depletion caused by intensive agriculture , modern foods may provide less magnesium than we think. This explains why, for some people, even with a varied diet, it can be difficult to reach the Recommended Daily Intake (RDI) through food alone.

👉 Food supplements should not be used as a substitute for a varied and balanced diet , but as support to reach the appropriate amount.

Magnesium can be combined without problems with most common supplements, such as vitamin D, calcium or collagen , since they act through complementary pathways in bone, muscle and general health.

It's sometimes said that magnesium and calcium "compete" and are absorbed less effectively when taken together. This can happen under laboratory conditions and at very low doses , but at the usual amounts found in supplements, it doesn't typically pose a real problem.

With medications, it's advisable to be more cautious: magnesium can interfere with the absorption of some drugs (for example, certain antibiotics or thyroid treatments). In these cases, simply separate the dosage by a couple of hours.

👉 In summary: in healthy people there is usually no problem combining it, but if you are under medical treatment , it is advisable to consult your doctor to adjust the timing of intake.

There's no need to take scheduled breaks from magnesium supplementation. Unlike other nutrients, magnesium doesn't accumulate in excess in the body: the body regulates its levels and eliminates what it doesn't need through urine.

The important thing is to maintain an adequate and constant intake , since magnesium participates in daily processes such as muscle and nerve function and energy balance.

👉 Only in specific cases (prolonged medical treatments, kidney disease or special guidelines) should you consult with a professional to determine if it is appropriate to adjust the duration or dose.

Magnesium contributes to normal muscle function by regulating contraction and relaxation. Therefore, it can be a helpful supplement for people with frequent cramps when intake is insufficient or demand is increased (due to exercise, stress, menopause, or advanced age).

• Magnesium citrate is a good option for muscle as long as it is taken with food .
• In people with hypochlorhydria (low gastric acidity, common with age or due to the use of antacids), chelated forms, such as bisglycinate , are recommended, which do not depend on stomach acid for absorption.

Regarding intestinal transit , some poorly absorbed salts (oxides, chlorides, carbonates) can produce an osmotic laxative effect by drawing water into the intestine. Magnesium citrate , taken between meals or in cases of hypochlorhydria, can also have this effect in some people.

Magnesium can be safely combined with these supplements, as each one fulfills different and complementary functions:

• Collagen → Collagen provides structure to bones, joints, and tissues, while magnesium is involved in muscle contraction, energy metabolism, and protein synthesis . Combining them can be useful in bone and joint health strategies.
• Probiotics → there is no known negative interaction. In fact, a healthy gut with a good microbiota promotes the absorption of minerals such as magnesium.
• Calcium → It is sometimes said that magnesium and calcium compete for absorption. This only occurs under experimental conditions and at very low doses. In common supplements, it doesn't usually pose a real problem, which is why they are formulated together in many bone health products.

👉 In summary: magnesium can be taken alongside collagen, probiotics, and calcium without any problems. The key is that supplementation is tailored to each individual and their diet , keeping in mind that supplements are not a substitute for a healthy lifestyle.