Editor’s Note: Sarah Mayhill, M.D., is a British doctor working both for the National Health Service and with a private practice. About 10% of her NHS patients suffer from CFS and approximately 70% in her private practice have it. Dr. Myhill is a medical advisor to Action for ME, a national support organization in the UK for ME/CFS sufferers. She is also the Honorary Secretary of the British Society for Allergy Environmental and Nutritional Medicine.
Dr. Myhill has written extensively about CFS over the years, covering all aspects of the disease from diagnosis to causal theories to treatments. This excerpt is adapted from her book “Diagnosing and Treating Chronic Fatigue Syndrome”, and is used with permission of the author.
Treating Magnesium Deficiency
Magnesium deficiency is the most difficult deficiency to correct. In evolutionary terms, magnesium was abundant in the diet and therefore no good mechanisms to conserve magnesium evolved. It appears to be poorly absorbed and easily excreted even by so- called normal people (and I don’t think there are many of those left!).
Magnesium is necessary for the normal function of over 300 enzyme systems, for muscle relaxation, immune function, cardiac function, clotting, nerve conduction etc. Indeed I cannot think of a bodily department in which magnesium is not essential…
I can guarantee to get magnesium levels up by using injections. One injection of 2mls of 50% magnesium sulphate (1gm MgSO4, or 100mgs elemental Mg or 4 millimols) will usually keep levels up for two weeks (however, some people need them more often). By the third week, levels will usually have fallen again. For some people this is the only method that has worked, but it is tedious to have to keep injecting. It astonishes me that so small a dose of magnesium works as 100mgs is only one third of the RDA (recommended daily allowance).
There are other interventions to improve magnesium levels and some work for some people. It is impossible to predict which will work for everyone but all are worth trying.
What is Sufficient Magnesium?
Are you taking enough magnesium in the diet? The recommended daily allowance is 300mgs for men, 350mgs for women. Magnesium is extremely safe by mouth – too much simply causes diarrhea. I have yet to see a red cell magnesium which is too high. However, it is theoretically possible in people with kidney failure.
The richest source of magnesium in the diet is from chocolate (yippee, but care with the sugar!), nuts, green vegetables, whole grains and seeds. Use a magnesium rich salt such as Solo. Use a bottled water rich in magnesium. Hard water also contains more magnesium than soft water. Most processed foods are low in magnesium.
Can magnesium be supplemented? Yes, of course. Too much magnesium can cause diarrhea in which case your magnesium levels will fall. I am cautious about using minerals in isolation, because too much of one can induce deficiencies in others. So I start off with a mineral complex daily (each capsule of the brand I usecontains 90mgs of magnesium). If this does not do the trick, add in other magnesium salts such as Epsom salts (1/4 to ½ teaspoon daily – too much gives diarrhea), magnesium citrate, chelated magnesium, magnesium EAP.etc.
Try Epsom salts in the bath because minerals can be absorbed through the skin. I do not know exactly how much to use, but I suggest a handful or two.
Is Magnesium’s Absorption Blocked?
Calcium and magnesium compete for absorption and so too much calcium in the diet will block magnesium absorption. Our physiological requirements for calcium to magnesium is about 2:1. In dairy products the ratio is 10:1. So, consuming a lot of dairy products will induce a magnesium deficiency.
Tea contains tannin which binds up and chelates all minerals including magnesium. If tea is to be drunk, don’t have it with food. Incidentally, tea drinking is the commonest cause of iron deficiency anaemia in UK for this same reason.
Vitamin D is necessary for the body to utilize magnesium. The major sources of vitamin D are dairy products, sunshine on the skin, and seafoods (at least 3 servings a week).
Are You a Magnesium Loser?
All diuretics will make you lose magnesium through urination. By this I do not just mean drugs, but also tea, coffee and alcohol. Even some herbal teas are mildly diuretic.
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Hyperventilation makes you lose magnesium in the urine. This is because hyperventilation induces a respiratory alkalosis, the body excretes out bicarbonate to compensate, but each bicarbonate is negatively charged and carries a positively charged cation with it – in this case magnesium.
Heavy exercise also makes you lose magnesium in the urine. This should not be a problem for CFS patients but does explain why long distance runners may suddenly drop dead with heart arrhythmias.
Magnesium is lost at times of stress. This also includes food allergy reactions and detoxification.
Can You Hang on to Magnesium?
For magnesium to get into cells it requires thiamine (vitamin B1). Try thiamine 100mgs daily – if you are already taking some in a multivitamin preparation, then take the B1 at 100mg a day.
For magnesium to be retained inside cells you need good antioxidant status. Selenium is the main mineral antioxidant. Food tables are unreliable because food content is dependent on soil levels of selenium. Assuming good soil levels, (which is a big assumption), foods rich in selenium include wholegrains, organ meats, butter, garlic and onion. Seafoods are rich in selenium and obviously not dependent on soil levels.
Boron is necessary for normal calcium and magnesium metabolism. I also find boron very useful for arthritis, perhaps because of its effect on calcium and magnesium. For arthritis you need 9mgs a day for 3 months, then reduce to a maintenance dose of 3-6mgs daily.
At present the only way I know how to ascertain whether or not magnesium levels are replete is to measure a red cell magnesium.
Magnesium by Injection
Parenteral magnesium is often used as part of the treatment of myalgic encephalitis (ME). It can have many effects but the main ones are to improve energy, muscle aches, cold hands and feet and help hyperventilation. It seems to have a different effect from oral magnesium and, even in the presence of a normal red cell magnesium, can bring benefits. However, it is usually given to those patients who are deficient. A red cell magnesium is a reasonable test of levels. A serum magnesium is an unhelpful test since the heart stops if these levels fall. Therefore serum magnesium is maintained at the expense of body stores. Unfortunately most hospital laboratories only measure serum levels – usually in intensive care medicine.
Magnesium sulphate is available on prescription, (in the UK). The usual regime is 1gm/2mls given intramuscularly, weekly for 10 weeks. About 70% of patients will see useful improvement. After this time about 50% of those who have improved will need a top-up dose every 1-4 weeks depending on clinical response. 1gm of 50% contains 100mgs of elemental magnesium. Some of my patients have received over 50 injections. Since the RDA (recommended daily allowance) for magnesium is 300mgs, it is almost impossible to overdose. A possible risk may be to a patient in advanced renal failure, who cannot excrete magnesium and may already have high levels.
The injection is painful because one is injecting a concentrated solution. It is best given at room temperature or blood heat, intramuscularly, either into triceps or deltoid, slowly over one to two minutes. I usually use an orange needle, at least 1” long to get deep into the muscle. Magnesium is a powerful vasodilator. Even if one takes care to check the tip of the needle is not in a vein, sometimes there is such a powerful local vasodilatation that the vessels open up and an i.v. injection is inadvertently given. This does not matter much, except that the patient develops a generalised vasodilatation, feels hot and alarmed, goes red and may faint (if upright)….
I have recently discovered that for magnesium to get into cells thiamine is required. Some patients can correct levels by taking thiamine 100mgs daily.
Magnesium Per Rectum
Giving magnesium by injection is the quickest way of restoring normal blood and tissue levels of magnesium. However for some patients the injections, while giving benefit, are too painful to be considered long term.
At a recent conference in Australia, I spoke to a doctor who had been trying magnesium sulphate given PR (per rectum – like a suppository) with some success. If this technique works, then it would be a cheap, safe, do-it-yourself at home technique, which could replace uncomfortable injections. With this in mind, Dr Keith Eaton made up some kits for my patients (and his) to try. I have now tried magnesium PR with 10 patients and it has been as effective as the injections in six of them.
If the magnesium is being absorbed then I would expect patients to get the same response as from a magnesium injection, but of course without the pain. It does work for a useful proportion of CFS patients, so it is well worth trying if you get benefit from the magnesium injections.
Magnesium by Mouth
Magnesium is poorly absorbed by mouth. That is why I start off with injections. By injecting magnesium I can guarantee 100% to bring the levels up. I cannot guarantee to do this with either PR or oral magnesium. However if the injections do help then it is well worth trying oral or PR if only to reduce the pain and trouble of injections.
All magnesium salts can cause diarrhea if too much are taken. The cheapest source of magnesium is Epsom salts. The key is to take “sub-diarrheal” doses. I suggest a quarter teaspoon daily, building up slowly until you get “the trots”, then reduce just enough to give a normal bowel movement. It does taste awful – try with fruit juice.