Category: Minerals

Magnesium 鎂

Overview

Every organ in the body, especially the heart, muscles, and kidneys, needs the mineral magnesium. It also contributes to the makeup of teeth and bones. Most important, it activates enzymes, contributes to energy production, and helps regulate calcium levels, as well as copper, zinc, potassium, vitamin D, and other important nutrients in the body.

You can get magnesium from many foods. However, most people do not get as much magnesium as they should from their diet. Foods rich in magnesium include whole grains, nuts, and green vegetables. Green leafy vegetables are particularly good sources of magnesium.

Although you may not get enough magnesium from your diet, it’s rare to be severely deficient in magnesium. Certain medical conditions, however, can upset the body’s magnesium balance. For example, an intestinal virus that causes vomiting or diarrhea can cause temporary severe magnesium deficiencies. Some gastrointestinal diseases (such as irritable bowel syndrome or IBS and ulcerative colitis), diabetes, pancreatitis, hyperthyroidism (high thyroid hormone levels), kidney disease, and taking diuretics can lead to deficiencies. Too much coffee, soda, salt, or alcohol, as well as heavy menstrual periods, excessive sweating, and prolonged stress can also lower magnesium levels.

Symptoms of magnesium deficiency may include agitation and anxiety, restless leg syndrome (RLS), sleep disorders, irritability, nausea and vomiting, abnormal heart rhythms, low blood pressure, confusion, muscle spasm and weakness, hyperventilation, insomnia, poor nail growth, and even seizures.

Uses

Getting enough magnesium may enhance the effectiveness of conventional treatment for the following conditions:

Asthma
Several studies show that intravenous (IV) magnesium and magnesium inhaled through a nebulizer can help treat acute attacks of asthma in children 6 – 18 years of age, as well as adults. Low levels of magnesium may increase risk of developing asthma. A population based clinical study of more than 2,500 children 11 – 19 years of age found that low dietary magnesium intake may be associated with risk of asthma. The same was found in a group of more than 2,600 adults 18 – 70 years of age.

Depression
Inadequate magnesium appears to reduce serotonin levels, and antidepressants have been shown to raise brain magnesium. A 2008 study found that magnesium was as effective as the tricyclic antidepressants in treating depression among people with diabetes.

Diabetes
People who have type 2 diabetes often have low levels of magnesium in the blood. A large clinical study of over 2,000 people found that getting more magnesium in the diet may help protect against developing type 2 diabetes. Some studies suggest that taking magnesium supplements may help blood sugar control and insulin sensitivity in people with diabetes or prediabetes.

Noise related hearing loss
One study suggests that taking magnesium may prevent temporary or permanent hearing loss due to very loud noise.

Arrhythmia and heart failure
Magnesium is essential to heart health. Studies suggest a possible association between a modestly lower risk of CHD in men and increased magnesium intake. In one study of women, higher dietary intakes of magnesium were associated with a lower risk of sudden cardiac death. Magnesium helps maintain a normal heart rhythm and is sometimes given intravenously (IV) in the hospital to reduce the chance of atrial fibrillation and cardiac arrhythmia (irregular heartbeat). People with congestive heart failure (CHF) are often at risk for developing cardiac arrhythmia.  One well designed study found that taking magnesium orotate for a year reduced symptoms and improved survival rates compared to placebo in people with CHF. Magnesium and calcium work together at very precise ratios to ensure your heart functions properly.

Results of studies using magnesium to treat heart attack survivors, however, have been mixed. Some have reported lower death rates, as well as fewer arrhythmias and improved blood pressure when magnesium is used as part of the treatment following a heart attack.

High blood pressure
Eating low fat dairy products, along with lots of fruits and vegetables on a regular basis, is associated with lower blood pressure. All of these foods are rich in magnesium, as well as calcium and potassium. A large clinical study of more than 8,500 women found that a higher intake of dietary magnesium may decrease the risk of high blood pressure in women. A few studies also suggest that magnesium supplements may help lower blood pressure, although not all studies agree.

Migraine headache
A few studies suggest that taking magnesium supplements may help prevent migraine headaches. In addition, a few clinical studies suggest that magnesium supplements may shorten the duration of a migraine and reduce the amount of medication needed. People who have migraine headaches tend to have lower levels of magnesium compared to those with tension headaches or no headaches at all.

Some experts suggest combining magnesium with the herb feverfew along with vitamin B2 (riboflavin) may be helpful when you have a headache.

However, some studies suggest that magnesium sulfate may be less effective than prescription medications for preventing migraines in those who have 3 or more headaches per month. The only exception to this may be women who get migraine headaches around the time of their period.

Osteoporosis
Not getting enough calcium, vitamin D, magnesium, and other micronutrients play a role in the development of osteoporosis. To prevent osteoporosis, it is important to get enough calcium, magnesium, and vitamin D; to eat a well balanced diet; and to do weight bearing exercises throughout life.

Preeclampsia and eclampsia
Preeclampsia is characterized by a sharp rise in blood pressure during the third trimester of pregnancy. Women with preeclampsia may develop seizures, which is then called eclampsia. Magnesium, given in the hospital intravenously (IV), is the treatment of choice to prevent or treat seizures associated with eclampsia or to prevent complications from preeclampsia.

Premenstrual syndrome (PMS)
Scientific studies suggest that magnesium supplements may help relieve symptoms associated with PMS, particularly bloating, insomnia, leg swelling, weight gain, and breast tenderness. One study suggests that a combination of magnesium and vitamin B6 may work better than either one alone.

Dietary Sources

Rich sources of magnesium include tofu, legumes, whole grains, green leafy vegetables, wheat bran, Brazil nuts, soybean flour, almonds, cashews, blackstrap molasses, pumpkin and squash seeds, pine nuts, and black walnuts. Other good dietary sources of this mineral include peanuts, whole wheat flour, oat flour, beet greens, spinach, pistachio nuts, shredded wheat, bran cereals, oatmeal, bananas, and baked potatoes (with skin), chocolate, and cocoa powder. Many herbs, spices, and seaweeds supply magnesium, such as agar seaweed, coriander, dill weed, celery seed, sage, dried mustard, basil, cocoa powder, fennel seed, savory, cumin seed, tarragon, marjoram and poppy seed.

It is a good idea to take a B vitamin complex, or a multivitamin containing B vitamins, because the level of vitamin B6 in the body determines how much magnesium will be absorbed into the cells.

Upper Limits

The Council for Responsible Nutrition recommends an upper limit of 400 mg per day (supplemental) for healthy adults.

Sources

University of Maryland Medical Center
Council for Responsible Nutrition

Phosphorus

Overview

Next to calcium, phosphorus is the most abundant mineral in the body. These two important nutrients work closely together to build strong bones and teeth. About 85% of phosphorus in the body can be found in bones and teeth, but it is also present in cells and tissues throughout the body. Phosphorus helps filter out waste in the kidneys and plays an essential role in how the body stores and uses energy. It also helps reduce muscle pain after a hard workout. Phosphorus is needed for the growth, maintenance, and repair of all tissues and cells, and for the production of the genetic building blocks, DNA and RNA. Phosphorus is also needed to help balance and use other vitamins and minerals, including vitamin D, iodine, magnesium, and zinc.

Most people get plenty of phosphorus in their diets. The mineral is found in milk, grains, and protein rich foods. Some serious health conditions such as diabetes, starvation, and alcoholism can cause levels of phosphorus in the body to fall. The same is true of conditions that make it hard for people to absorb nutrients, such as Crohn’s disease and celiac disease. Some medications can cause phosphorus levels to drop, including some antacids and diuretics (water pills). Symptoms of phosphorus deficiency include loss of appetite, anxiety, bone pain, fragile bones, stiff joints, fatigue, irregular breathing, irritability, numbness, weakness, and weight change. In children, decreased growth and poor bone and tooth development may occur.

Having too much phosphorus in the body is actually more common and more worrisome than having too little. Too much phosphorus is generally caused by kidney disease or by consuming too much dietary phosphorus and not enough dietary calcium. Several studies suggest that higher intakes of phosphorus are associated with an increased risk of cardiovascular disease. As the amount of phosphorus you eat rises, so does the need for calcium. The delicate balance between calcium and phosphorus is necessary for proper bone density and prevention of osteoporosis. Many soft drinks contain phosphoric acid, which increases the requirement for calcium. If the increase calcium requirements are not satisfied, such drinks can lead to calcium-deficiency issues.

Uses

Phosphates (phosphorus) are used clinically to treat the following:

  • Hypophosphatemia, low levels of phosphorus in the body
  • Hypercalcemia, high blood calcium levels
  • Calcium based kidney stones

Phosphates are also used in enemas as laxatives. Most people get plenty of phosphorus in their diets. Sometimes athletes use phosphate supplements before competitions or heavy workouts to help reduce muscle pain and fatigue, although it’s not clear how much it helps or if it improves performance.

 

Dietary Sources

Protein rich foods, such as meat, poultry, fish, eggs, dairy products, nuts, and legumes, are good sources of phosphorus. Other sources include whole grains, hard potatoes, dried fruit, garlic cloves, and carbonated beverages.

Upper Limits

As most people get plenty of phosphorous from their diets, supplementation is not recommended. The Council for Responsible Nutrition puts the upper limit for supplemental phosphorous at 1,500 mg / day, to maintain its optimal 1:1 ratio with calcium.

Source

University of Maryland Medical Center

Calcium

Overview

Calcium is the most abundant mineral in your body. It is essential for the development and maintenance of strong bones and teeth, where about 99% of the body’s calcium is found. In smaller amounts, it is essential to the proper function of the heart, nerves, muscles, and other body systems. It is probably best known for helping prevent osteoporosis.

Your body needs several other nutrients in order for calcium to be absorbed and used properly, including magnesium, phosphorous, and especially vitamins D and K.

The best way to get calcium is through food, although most people fail to absorb sufficient calcium for optimal health.

Postmenopausal women, people who consume large amounts of caffeine, alcohol, or soda, and those who take corticosteroid medications may need extra calcium supplements. More serious calcium deficiency can be found in people who don’t absorb enough calcium, as can happen with Crohn’s disease, celiac disease, and some intestinal surgeries.

Getting enough calcium may help prevent or treat the following conditions:

Osteoporosis

Your body needs calcium to help build and maintain healthy bones and strong teeth. People start to lose more bone than their bodies make in their 30s, and the process speeds up as they get older. Calcium, particularly in combination with vitamin D, helps prevent bone loss associated with menopause. It also helps prevent bone loss in older men. If you do not get enough calcium in your diet, your optimal health guide may recommend a supplement.

Hypoparathyroidism

People with this condition have underactive parathyroid glands. These four small glands sit on the four corners of the thyroid in the neck and produce a hormone that regulates calcium, phosphorous, and vitamin D levels in the body. People with this condition should follow a high-calcium, low-phosphorous diet .

Premenstrual Syndrome (PMS)

One large, well-designed study showed that women who took only 1,200 mg of calcium per day reduced their symptoms of PMS by 50%, including headache, moodiness, food cravings, and bloating. The reduction of pain-related symptoms by calcium is well documented and has been experienced by many clients.

High Blood Pressure

People who do not get enough calcium may be at higher risk for hypertension or high blood pressure. Calcium increases the flexibility of blood vessels and can contribute to a reduction in blood pressure.  Calcium is also essential for the heart, as it contributes to muscle strength and flexibility.

 

High Cholesterol

Preliminary studies in animals and people suggest that calcium supplements, in the range of 1,500 – 2,000 mg per day, may help to lower cholesterol slightly. From these studies, it seems that calcium supplements, along with exercise and a healthy diet, may be better at keeping cholesterol at normal levels than at lowering already high cholesterol.

Rickets

Rickets is a condition of severely low calcium intake that causes softening and weakening of the bone in children. Although very rare in North America and Western Europe, where children drink a lot of milk, it still happens in many parts of the world. This condition can be caused by a vitamin D deficiency, vitamin K deficiency or inadequate intake of calcium.

Dietary Sources

The richest food sources of calcium include cheeses, such as parmesan, Romano, gruyere, cheddar, American, mozzarella, and feta; low-fat dairy products, such as milk and yogurt; tofu; and blackstrap molasses. Some other good sources of calcium include almonds, brewer’s yeast, bok choy, Brazil nuts, broccoli, cabbage, dried figs, kelp, dark leafy greens (such as dandelion, turnip, collard, mustard, kale, and Swiss chard), hazelnuts, oysters, sardines, and canned salmon.

Foods that are often fortified with calcium, such as juices, soy milk, rice milk, tofu and cereals, are also good sources of this mineral.

Supplemental Upper Limits

The Council for Responsible Nutrition recommends an upper limit of 1,500 mg supplemental calcium per day in addition to normal dietary calcium.

A number of hypotheses for adverse effects of excess calcium intake have been investigated over the years, including kidney stones (nephrolithiasis) (Johnson et al. 1979), hypercalcemia with renal insufficiency (milk-alkali syndrome) (Junor and Catto 1976; Orwoll 1982), and harmful calcium interactions with other minerals (Spencer et al. 1965; Clarkson et al. 1967; Schiller et al., 1989). The evidence regarding a link to an increased risk of kidney stones with high calcium intake from foods and supplements is inconsistent, with some studies associating higher calcium intakes with decreased risk of kidney stones (Curhan et al. 1993).

Source

University of Maryland Medical Center