Modern medicine is often flummoxed by heart disease.
A number of different risk factors—high blood pressure, hardened arteries, high cholesterol and heart rhythm abnormalities—can all beset the same person, and the only way that doctors know how to counteract these conditions is by prescribing a separate drug for each of them.
As a consequence, a growing problem in the standard treatment of heart disease is to avoid making matters worse with all the side-effects and interactions caused by prescribing so many drugs.1
Doctors of orthomolecular (nutrition-based) medicine take a different approach to cardiac illness by attempting to identify and correct the potential nutritional deficiencies that may lie at the core of these physiological imbalances.
The roles of vitamin D, omega-3 fatty acids, antioxidants and B vitamins in heart conditions are currently under investigation, but one connection firmly stands out: the relationship between low levels of magnesium and the risk of heart disease.2
Population studies reveal the link between magnesium and a healthy heart. Variations in cardiovascular disease risk across different countries, and even between different parts of the same country, have been shown to roughly correlate with regional variations in magnesium levels in soil and water.3 In fact, diets rich in vegetables and fruits, nuts, seeds and whole grains, currently recommended to reduce the prevalence of cardiovascular disease, also happen to be high in magnesium.4
A natural ‘drug’
Magnesium is a calcium antagonist, which means that it competes with calcium for absorption and reabsorption in the kidneys,5 and for influx into cells. Because of this action, magnesium has been dubbed ‘nature’s calcium-channel blocker’.6 Adequate levels of magnesium in the diet have helped to prevent and even reduce arterial calcification and injury to blood vessel walls, at least in animal models.7
Magnesium is also closely involved in maintaining cellular electrolyte (fluid and mineral) balance. Adequate amounts of dietary magnesium are needed to maintain normal levels of potassium,8 which is well known to be important for regular heart rhythm.
This all-purpose mineral also plays a pivotal role in the regulation of skeletal, cardiac and smooth-muscle relaxation after muscle contraction.9 Levels of calcium need to rise in muscle cells for contraction to happen, but before relaxation can follow, calcium must be either removed from muscle cells or sent back to storage sites within cells.
This process also depends on the availability of magnesium.10 If your intake of magnesium is inadequate, the ability of your smooth and cardiac muscles to relax will be impaired, and your risk of ‘heart flutters’ (fast or irregular heart beats), high blood pressure and sudden constriction of heart and brain blood vessels will be increased, potentially leading to cardiac arrest and stroke.11
Lab studies involving cell cultures and animal tissues have shown that a deficiency of magnesium affects the function and structure of the tissues lining the heart and arteries, and it’s well known that the integrity of the arterial lining is critical for preventing atherosclerosis. All this suggests that correcting low magnesium may be a useful and cost-effective way to prevent and treat cardiovascular disease.12
Magnesium and cholesterol regulation
Magnesium is also required for the regulation of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the enzyme that controls cholesterol production. In this case, magnesium shares some of the effects as the widely used statin drugs, which work by inhibiting this enzyme.
But statin drugs continuously inhibit cholesterol production, so limiting its availability for cell-membrane synthesis and repair, sex and stress hormones, and vitamin D, whereas magnesium is highly discriminating, switching HMG-CoA activity on and off as needed.13
Another unwanted side-effect of statins is a lowering of circulating testosterone, which protects against cardiovascular disease risk in both men and women,14 whereas supplementing with magnesium has been shown to increase total testosterone levels in men.15
Magnesium also has anti-inflammatory properties. Deficiencies of this vital nutrient lead to immune-system and oxidative stress, thereby increasing your body’s overall level of inflammation which, in turn, stimulates a cascade of events resulting in dysfunctional blood vessels and blood-clotting, and changes in the ways fats are metabolized.16
In one study, 14 postmenopausal women were asked to restrict their intake of magnesium to 33 percent of the Recommended Dietary Allowance (RDA), a level of intake not uncommon in those eating a typical Western-style diet. In just 78 days (and some as early as 42 days), the women were showing heart arrhythmias, increases in blood sugar and altered levels of cholesterol, among other effects.17
Magnesium levels are maintained at a delicate balance within a narrow range by the small intestine and kidneys. If your intake is too high, the kidneys get to work and increase its excretion. When intake falls, the small intestine and kidneys increase their magnesium absorption. If your magnesium levels continue to fall, the body seeks to restore them by robbing the magnesium stores in your bones.18
This means your ongoing magnesium status depends on the health of both these organs: magnesium deficiency is a known complication of inflammatory bowel disease,19 while serious kidney disease may result from high blood concentrations of magnesium.20
There are lots of reasons why people are deficient in magnesium. They could have a genetic inability to absorb or retain magnesium, or their bodies could be excreting excessive amounts of it because they’re stressed or not eating enough magnesium-rich foods.21
But the main culprit is our modern-day diet. In many Western nations, dietary intakes of magnesium are woefully deficient. In Canada, the estimated daily intake in those eating an average diet is between 200 and 300 mg daily,22 lower than the RDA of 320 mg/day and 420 mg/day for women and men aged over 30, respectively, and well below the optimal levels of 500–750 mg/day.23 In the US, the 1999–2000 National Health and Nutrition Examination Survey (NHANES) found
that 79 percent of adults had magnesium intakes below the RDA.24
Apart from diet, a number of medical conditions can also influence magnesium status, including chronic diarrhea and vomiting,18 excessive urination due to poorly controlled diabetes,25 intense and/or prolonged exercise,26 and excessive alcohol intake.27
Another major culprit is prescribed drugs, ironically including some that are targeted at heart disease, such as loop diuretics like furosemide (Lasix) and thiazide diuretics like indapamide (Natrilix).
Recently, the US Food and Drug Administration FDA) issued a drug-safety announcement warning that proton pump inhibitors, including omeprazole (Prilosec), lansoprazole (Prevacid) and esomeprazole (Nexium)—all commonly prescribed for treating gastroesophageal reflux (heartburn)—can seriously deplete magnesium, potentially causing leg cramps, muscle twitches and weakness, tremors, muscle
spasms, seizures and heart flutters (irregular or rapid heart beats).28
The FDA also emphasized that the situation could be magnified in people taking other drugs known to deplete magnesium, such as digoxin and diuretics, both commonly given to cardiovascular disease patients.
Stress kills magnesium levels
Magnesium levels are also depleted by stress.29 And when we live with prolonged stress, our adrenal hormones trigger a fall in magnesium levels within our cells. This results in an influx of calcium into nerve cells which, in turn, causes constriction of all types of muscle cells, but particularly those in cardiac and vascular smooth muscle, as these are tasked with responding rapidly to sudden acute stress.30
This reaction is a necessary preparation for the ‘fight-or-flight’ response. Under normal conditions, the muscle cells return to a relaxed state once the emergency is past. But when stress is chronic and magnesium levels are deficient, these skeletal, cardiac and vascular muscles will remain in a state of sustained contraction.31
Calcium and magnesium levels in our bodies work together, but there’s been a dramatic shift in our calcium-to-magnesium balance with our current diets. Unlike those of our hunter–gatherer forebears, modern diets are low in magnesium and, because of the ready availability and consumption of dairy, much higher in calcium. The combination of modern dietary changes, popular use of magnesium-depleting drugs, high levels of stress due to urban lifestyles and increased intakes of calcium supplements to prevent osteoporosis has tended to raise intracellular calcium and lower magnesium, so increasing the threshold at which these muscles all remain contracted.
In fact, large studies of people taking calcium supplements without also taking magnesium or checking magnesium intakes have shown a link with an increased risk of heart disease in both men and women.32
Changes in calcium–magnesium balance and deficiencies of these minerals in the modern-day diet together can increase our vulnerability to cardiovascular disease.
Unless you have kidney failure, the most effective way to improve your magnesium status is to take oral supplements. Although a standard dose of 5 mg/kg body weight/day has been proposed, so that a person weighing 70 kg (154 lb) would require 350 mg/day,33 individual needs for magnesium are actually hard to predict and will vary even in the same individual, depending on stress levels, diet and drugs being taken at the time.
One tried-and-tested method for optimizing your magnesium levels is to increase your intake to the point of bowel intolerance (taking increasing dosages until you experience loose stools, which means you’ve taken too much). Your optimal level would then be the dosage just before that.
When increasing your levels of magnesium, it’s also important to not overwhelm your gastrointestinal capacity to absorb it. A very gradual increase in magnesium (every three or four days) with small incremental doses (around 50 mg of elemental magnesium) to generate one to two soft bowel movements daily achieves the best outcomes, and should result in a gradual disappearance of symptoms.
If you’re suffering from anxiety, fatigue, headaches, insomnia or hair-trigger emotions, you should see relief. You should also notice improvement in mood, sleep and energy levels.
One of the most digestible forms of magnesium is magnesium citrate. While magnesium oxide has a higher concentration of elemental magnesium by weight, it is not absorbed as well as citrate salts.34 To achieve the best outcomes, divide the dose between morning and evening.
A poor magnesium status has profound implications for health in general, but has particular relevance to heart disease, as it influences all of the major risk factors. Besides supplementing, aim to eat an organic, whole-food diet high in fruits, vegetables and whole grains, with about two-thirds of your daily energy (calories) coming from plant foods and the remaining third from animal products. If you’re consuming, say, 2,100 kcal of food, it should include about 1,100 mg of calcium and 800 mg of magnesium, a good ratio for maintaining a healthy heart.35
Why is magnesium important?
Magnesium is a required cofactor for over 300 regulatory enzymes, with virtually all hormonal reactions depending on magnesium. It’s also indirectly involved in all processes using the body’s enzymes, as adenosine triphosphate (ATP), a molecule which stores and transports all the energy needed by the body to stay alive, must bind with a positive magnesium ion to be metabolically available.
We now know that the levels of magnesium in your body affect cholesterol levels, blood pressure and calcification in your arteries, and a deficiency of this vital mineral is a known risk factor for atrial fibrillation (irregular and too-rapid heart beats). This suggests that all seemingly separate heart conditions may show up in a given individual simply because of an inadequate intake of this critically important mineral.
Good food sources of magnesium
- Halibut & shrimp
- Whole-grain breads & oats
- Beans & legumes
- Leafy vegetables
- Seeds & nuts
- Dark chocolate
Dark chocolate has also been shown to lower blood pressure, improve vascular function and glucose metabolism, and reduce the formation of blood clots and adhesions in arterial walls.1
Here’s the amount of magnesium present in a sample of foods:
Mixed nuts: ½ cup = 150mg
Pumpkin seeds: ½ cup = 350mg
Black beans: 1 cup = 120mg
Chocolate (baking): 3.5oz = 295mg
Halibut 3oz = 70mg
How to tell if you’re deficient in magnesium
Laboratory tests for magnesium status are notoriously inaccurate.1 A fall in magnesium blood levels is quickly normalized from stores of it in bone and in cells; also, as it’s not stable in blood cells, measuring magnesium by conventional standards (in serum, plasma or red blood cells) won’t provide a true picture.
One alternative approach that requires no lab tests looks at the symptoms. Inadequate tissue stores of magnesium show up as malfunctions of skeletal muscle, such as leg cramps and spasms (a charley horse), muscle twitches, restless legs syndrome and tight muscles.
Imbalances are also obvious in smooth muscle, resulting in physical signs of unregulated lung function like shortness of breath, wheezing and asthma, and even frequent sighing.
Other possible clues are poor bladder tone—which is dependent on calcium–magnesium balance—especially at night when magnesium needs are highest, and constipation, as magnesium plays a central role in relaxing gastrointestinal smooth muscle.2
Although there are loads of other symptoms, ticking ‘yes’ to one or more of the following might quickly identify whether you’re lacking in magnesium, and all symptoms should resolve after appropriate magnesium supplementation.
- Do you get leg or foot cramps?
- Are your shoulders frequently tight or tense at the end of the day?
- Does your back ever go into spasm?
- Do you ever experience muscle-twitching, especially around the eyes?
- Do you suffer from wheezing or asthma, especially after exercise?
- Do you experience shortness of breath when climbing stairs, for example?
- Do you sigh frequently?
- Do you ever have palpitations or notice an irregular heart beat?
- Do you need to urinate frequently, especially at night?
- Are you ever constipated?