I have doubts. How is possible that the Premtesse tablets are so small compared with MagAsorb tablets if Premtesse have more Magnesium?.
R/ The clue would be in the form of magnesium.
So in Magasorb we use citrate whereas in Premtesse we use oxide. We always state the elemental magnesium in our formulas, so in this way Magasorb contains 150mg of pure magnesium and Premtesse contains 400mg of pure magnesium. This is the main difference as many competitors will cite the magnesium salt as the quantity and only few will cite the elemental quantity – for example one company cites.
Magnesium Succinate (providing 72mg elemental magnesium) 425mg
Oral magnesium supplements combine magnesium with another substance such as a salt. Examples of magnesium supplements include magnesium oxide, magnesium sulfate, magnesium carbonate and magnesium citrate.
Elemental magnesium refers to the amount of magnesium in each compound. Figure 1 compares the amount of elemental magnesium in different types of magnesium supplements:
How to calculate the table: Mineral supplements are mostly salts – consisting of the cation (usually what you’re interested in) and an anion partner. Cations are positively charged; anions are negatively charged. You only care about the cation, and not the anion, so the anion essentially becomes a filler. Consider Magnesium Citrate. It has a molecular weight of 214.41 g mol. Magnesium has a molecular weight of 24.31. So Mg is 24/214ths or 11% Mg by weight. So every 100 mg of magnesium citrate has just 11 mg of useful Mg! Therefore you need a lot of Magnesium Citrate to make up 150mg of elemental magnesium found in Magasorb – hence the large tablets! Consider Magnesium oxide now. Molecular weight of 40.30, so 60% Mg by mass. 100 mg of magnesium oxide has 60 mg magnesium.
If you took Mg oxide with a meal (as we recommend for the Lamberts multi vitamins), you’d get a higher absorption. Citrate helps you absorb nearly all the Mg present, but it’s takes a lot of bulk to do so. Many people believe that 400mg of magnesium oxide – the whole salt – is a lot, but in reality only 8mg is actually absorbed. which is very little. As stated above our formulations only give the elemental value hence why we add the salt form as brackets alongside the word ‘magnesium’ in our technical catalogues.
Further to our own clinical testing conducted by Dr Sam Christie in a paper called ‘Mg citrate found more bio available than other Mg preparations in a randomised, double-blind study’ we added a Magnesium Citrate to our range alongside a Calcium Citrate product. The tablet size of these products are larger due to the citrate salt being a larger molecule and so for formulations where we need to feature magnesium or calcium alongside other nutrients we use the oxide or carbonate compounds.
The main use of magnesium oxide in our range is in Osteoguard and in our multi vitamins where we need to fit in many ingredients. Data to support these uses includes a 2006 study which specifically demonstrates the effectiveness of magnesium oxide on bone mineral content: ”A randomised controlled study of effects of dietary magnesium oxide supplementation on bone mineral content in healthy girls” (Clin Endocrinol Metab. 2006). Magnesium Oxide is a safe and tolerated source of dietary magnesium. One of the earliest uses in medical intervention spans from 1810 when magnesium oxide was used to treat patients with uric acid stones. A 2007 article published in the Archives of Biomedical Biophysics cites numerous studies to suggest magnesium oxide intake as a treatment for hypertension. More recently, the University of Maryland Medical Centre has stated that magnesium oxide may be used to restore magnesium levels, may allay migraines, high blood pressure and also assist in the treatment of arrhythmia.
However if the practitioner needs to address a magnesium deficiency quickly, then we would recommend magnesium citrate over magnesium oxide.