What is magnesium?
Magnesium is a mineral and the fourth most abundant one in the human body. It is essential for good health, which means it has to be supplied in the diet as the body cannot make it. About 50% of the magnesium in our bodies is found in our bones, with most of the other half being found inside our cells, while only about 1% is found in our blood. It is required for more than 300 different enzyme reactions in the body, which means if it is not available in the body, these important biochemical reactions will be unable to take place.
How do you know whether you are deficient?
As magnesium has vital roles to play in the central nervous system, a deficiency will first manifest in emotional and behavioral symptoms. Assessing your answers to the following fifteen questions will highlight whether you are deficient or not, with more than eight "yes" answers meaning that you could do with more magnesium in your diet.
Magnesium deficiency questionnaire:
- Are you easily irritated?
- If a door slams does your heart jump, leaving you feeling jittery?
- Do you feel as if you are on edge?
- Does an interruption easily startle you?
- Do you feel tired most of the time?
- Does your heartbeat feel as if it’s always racing?
- Does your heartbeat feel irregular?
- Do you suffer from insomnia?
- Do you experience muscle spasm or cramps?
- Do you feel anxious?
- Do you find yourself constantly worrying about things?
- Do you find it difficult to sit still, always needing to be doing something?
- Would others call you restless?
- Do you feel as if your personality has changed over the last while?
- Do you sometimes feel confused while doing something, or looking for something?
(These questions have been compiled from references in the list below.)
So what exactly does magnesium do?
Magnesium is involved in a variety of critical tasks, which are essential for optimal physical and mental health:
- Magnesium supports mitochondrial functioning, being essential in the energy production process, by assisting with the metabolism of carbohydrates, fats, and proteins.
- It also assists in keeping blood sugar even, by influencing both the release and the activity of insulin. Refined sugars deplete the body of magnesium, zinc and other nutrients. It may, therefore, help to prevent and manage type 2 diabetes.
- Magnesium is also involved with neurotransmitter activity. It influences neural activity by reducing excitatory neurotransmitter release. It does this by controlling the activation of NMDA (N-methyl-D-aspartic acid) which means that excitation is controlled, and neural and neuromuscular hyperexcitability is avoided.
- Magnesium deficiency increases susceptibility to the physiological effects of stress, and magnesium administration has a protective effect.
- Magnesium moves from inside the cell to the outside of the cell during stressful experiences, which leads to an increase in urinary excretion, eventually depleting body stores.
- Magnesium functions at presynaptic fiber terminals, to lower or decrease transmitter release. Therefore, reduced magnesium at the synaptic level will lead to an increase of excitatory transmission, which will increase the release of excitatory neurotransmitters, such as glutamate, leading to increased excitation in the aging hippocampus. Therefore, deficiencies will affect cognitive performance, especially in the elderly and those exposed to stress.
- Magnesium regulates muscle and nerve function, and reduces the exaggerated response to stress, and does this partly by relaxing muscle spasms during the stress response. Research has indicated that this action may be beneficial for severe headaches.
- Magnesium’s ability to regulate the stress response, is due in part to its ability to improve cortisol and adrenal functioning because it is a required nutrient for the synthesis of cortisol and adrenalin.
- Magnesium’s action on muscles extends to the heart, facilitating steady rhythmic action, as well as regulating blood pressure.
- The immune system also benefits from this nutrient.
- Magnesium is also essential for the synthesis of essential fatty acids from ALA and LA into HUFAs.
- Tryptophan is converted into serotonin using, among other nutrients, vitamins B3, B6 and magnesium.
- Magnesium is also the mineral that allows the conversion of vitamin D into its active form.
- Magnesium also helps the absorption of calcium into bones, so may be useful in the prevention of osteoporosis.
A magnesium deficiency
Deficiencies in this nutrient will, therefore, lead not only to cognitive deficits, and hyperarousal, which can lead to hyperventilation, and eventually convulsions. It will also lead to metabolic dysfunction, which will result in low energy levels and weight gain. Mood disturbances, sleep problems, digestion difficulties, immune system disorders, muscle cramps, and an inability to handle normal stressors, are some of the health problems that can arise should you be deficient in magnesium.
Where can I find magnesium?
Magnesium is found in green leafy vegetables, as magnesium is the central atom in the chlorophyll molecule, the green pigment in plants. Nuts, such as almonds, cashews, pecans and brazil nuts as well as sunflower, pumpkin and sesame seeds contain magnesium, as do whole grains, cooked beans, green peas and potato skins. Bananas and dried figs also contain magnesium, as do artichokes and tomatoes. It is also found in dairy products and meat, but as they may be contaminated with pesticides and hormones, it is best not to rely on them as the primary source of your magnesium requirements.
What about calcium?
Calcium and magnesium have a complementary relationship, so you also need to include calcium-rich foods in your diet. Interestingly, dark green leafy vegetables, as well as almonds and seeds are also rich sources of calcium. Although many people believe that dairy products are the best source of bone health foods, they contain very little magnesium, so they don’t help the calcium find its way into your bones.
Do we get enough magnesium in our foods today?
No, most people don’t. And there are a number of reasons why this is the case. Here are some facts about the depletion of magnesium in our foods:
- Between 1940 and 1991 the content of magnesium in the vegetables available to us went down by 24% *
- In the same time period, the content in our fruit decreased by 16% *
- Between 1978 and 1991 it went down by nearly 40% in our vegetables *
- Crops are favored for their appearance, not for their nutritional content
- An increased use of NPK (Nitrogen/Phosphorous/Potassium) fertilizers, not balanced mineral additions to the soil
- Continuous crop-growing leads to mineral-depleted soils, as well as a reduction in essential fungi that help liberate minerals from the soil
- Inherent soil deficiencies, lack of organic matter, soil pH and oxidization
- Increased transport distances, as well as storage times and processing methods
- Increased intake of processed, highly flavored carbohydrate foods, high protein intake, saturated and damaged fat intake, take the place of unprocessed, natural foods that contain magnesium
(These are figures from the United Kingdom, but the trend seems to be similar for most industrialized countries).
Some things you may be doing to further deplete yourself of magnesium
- Stress, whether it is mental, physical or emotional, uses up loads of magnesium, simply because the adrenal glands use magnesium, among other things, to produce adrenalin. This means that there won’t be enough magnesium left to perform the other tasks that it has to perform to keep you healthy. Furthermore, ongoing stress will damage your memory, as the brain is very sensitive to cortisol, which is what ends up being produced when adrenaline has run its course. However, a certain amount of adrenaline is a good thing, otherwise, you may not be driven to get out of bed in the morning and pursue your goals. So it’s important to both manage the bad stress and provide the nutrients to produce adrenalin, which we need in the right quantity
- When you experience stress, your body will pull glucose out of your liver, where it is stored, to give you the energy to either fight or run away from the thing that has caused your stress response. After all, your body does not know that it may not be a real threat to your survival, but simply a frustrating traffic jam, an infuriating boss, or an impossible teenager that is causing your stress. When glucose is pumped into your bloodstream to be transferred to your muscles to handle the perceived threat, it causes a sudden rise in blood glucose, which leads to the point below.
- A sudden rise in blood glucose, or an unstable blood glucose level, sparks the release of adrenalin, as the body sees this imbalance as a stressor. When you eat something that is highly processed, and your blood glucose peaks up, the pancreas produces insulin to get the blood glucose into the cells. Unfortunately, this process also signals the adrenals to produce adrenalin, which will further deplete you of magnesium.
- Drinking coffee also sparks off your adrenal glands, as coffee contains caffeine, which signals the release of dopamine, which turns into adrenaline. This is how coffee gives you energy. So, with every cup of coffee, you are getting a stress hit and using magnesium.
What about a supplement?
The RDA for magnesium varies between males and females, and between adults and children. Also, the RDA may well be a very outdated system for assessing real needs for vitamins and minerals. After age 31 females' RDA is 320 mg and males' is 420 mg, while children from ages 4–8 require 130 mg, and from 14–18 they require 360 mg if female and 410 mg if male. Remember that people differ in their needs for vitamins and minerals, with some people needing a lot more than others, due to biochemical differences and metabolic variations. If symptoms of deficiency exist, it is important to have a physical examination. However, a simple blood test doesn’t give a good indication of magnesium levels as only 1% of the magnesium in the body is found in the blood. Supplementing with magnesium is not problematic, though, because the body will get rid of extra magnesium by producing loose bowel movements if you take in excess of what you need.
Different kinds of magnesium
There are different kinds of magnesium supplements available, which can be confusing if you are looking for a supplement. This is a list of the different types that are available, and what the differences between them are:
- Magnesium Citrate – is a form of magnesium that is sometimes used to clear the bowel prior to certain stomach procedures, so it can cause loose bowel movements. It is available in tablet form and is used for short-term supplementation.
- Magnesium Gluconate – is used to maintain adequate magnesium levels for long-term magnesium supplementation. It is available in tablet form
- Magnesium Lactate – is often used to correct a magnesium deficiency, although it can also be used to treat indigestion, heartburn or an upset stomach. It can be taken orally, in tablet form, but can also be administered via an injection if the deficiency is severe
- Magnesium Sulfate – is the form of magnesium used most commonly in multivitamins. At higher doses, it can be used to treat a magnesium deficiency. It can be used for both short-term and long-term supplementation and can be administrated in tablet form or via an injection.
- Magnesium Amino Acid Chelate – is a form of magnesium that is bound to one or more amino acids (protein building blocks) that help the magnesium to be absorbed more easily through the intestinal wall. These forms, therefore, have higher levels of bioavailability. Magnesium arginate is a good form of chelated magnesium, with Magnesium Glycinate, Malate and Taurates also being chelated, but not better than the previous forms of magnesium mentioned. Avoid Magnesium aspartate and glutamate as they have excitotoxic properties. Mixing a magnesium compound with an amino acid is not the same as a true reacted chelate compound.
- Magnesium Oxide – is used to maintain proper magnesium levels in the body, and can be used long term as a supplement.
- Magnesium Hydroxide – is used as an antacid and as a laxative, and can, therefore, be used occasionally to treat constipation. It should only be used short term.
The term "elemental" used when describing the type of magnesium refers to the amount of magnesium in the supplement, while the term "bioavailability" refers to the amount that is absorbed by the body, and therefore available for use in our cells and tissues. Most of the supplemental forms of magnesium are a combination of a number of these different types, and you may have to try a few different kinds to find which one works for you, although the soluble form and the chelated form are generally absorbed more efficiently by the body.
A fairly recent addition to magnesium supplement options is magnesium oil, which is a super concentrated form of magnesium. It is applied to the skin and purported to be absorbed by the body in this way. Although there is some research to support this choice, there may be more research required to assess whether this is a suitable form of supplementation for long-term use.
Try to get your magnesium needs met through eating more magnesium-containing whole foods, adding a supplement only if you feel your body needs more than your food can supply, and after discussing the various forms that may suit you with your doctor. If you have kidney disease it is very important to discuss magnesium supplementation with your doctor.
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