hypercalcemia

You have more calcium in your body than any other mineral. Calcium has many important jobs. The body stores more than 99% of its calcium in the bones and teeth to help make and keep them strong. The rest is throughout the body in blood, muscle and the fluid between cells. Your body needs calcium to help muscles and blood vessels contract and expand, to secrete hormones and enzymes and to send messages through the nervous system.

It is important to get plenty of calcium in the foods you eat. Foods rich in calcium include:

• Dairy products such as milk, cheese, and yogurt
• Leafy, green vegetables
• Fish with soft bones that you eat, such as canned sardines and salmon
• Calcium-enriched foods such as breakfast cereals, fruit juices, soy and rice drinks, and tofu. Check the product labels.

The exact amount of calcium you need depends on your age and other factors. Growing children and teenagers need more calcium than young adults. Older women need plenty of calcium to prevent osteoporosis. People who do not eat enough high-calcium foods should take a calcium supplement.

NIH: National Institutes of Health Office of Dietary Supplements

Most people have four pea-sized glands, called parathyroid glands, on the thyroid gland in the neck. Though their names are similar, the thyroid and parathyroid glands are completely different. The parathyroid glands make parathyroid hormone (PTH), which helps your body keep the right balance of calcium and phosphorous.

If your parathyroid glands make too much or too little hormone, it disrupts this balance. If they secrete extra PTH, you have hyperparathyroidism, and your blood calcium rises. In many cases, a benign tumor on a parathyroid gland makes it overactive. Or, the extra hormones can come from enlarged parathyroid glands. Very rarely, the cause is cancer.

If you do not have enough PTH, you have hypoparathyroidism. Your blood will have too little calcium and too much phosphorous. Causes include injury to the glands, endocrine disorders, or genetic conditions. Treatment is aimed at restoring the balance of calcium and phosphorous.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases

Vitamin D deficiency means that your body is not getting enough vitamin D to stay healthy.

Vitamin D helps your body absorb calcium. Calcium is one of the main building blocks of bone. Vitamin D also has a role in your nervous, muscle, and immune systems.

You can get vitamin D in three ways: through your skin, from your diet, and from supplements. Your body forms vitamin D naturally after exposure to sunlight. But too much sun exposure can lead to skin aging and skin cancer, so many people try to get their vitamin D from other sources.

The amount of vitamin D you need each day depends on your age. The recommended amounts, in international units (IU), are:

• Birth to 12 months: 400 IU
• Children 1-13 years: 600 IU
• Teens 14-18 years: 600 IU
• Adults 19-70 years: 600 IU
• Adults 71 years and older: 800 IU
• Pregnant and breastfeeding women: 600 IU

People at high risk of vitamin D deficiency may need more. Check with your health care provider about how much you need.

You can become deficient in vitamin D for different reasons:

• You don't get enough vitamin D in your diet
• You don't absorb enough vitamin D from food (a malabsorption problem)
• You don't get enough exposure to sunlight
• Your liver or kidneys cannot convert vitamin D to its active form in the body
• You take medicines that interfere with your body's ability to convert or absorb vitamin D

Some people are at higher risk of vitamin D deficiency:

• Breastfed infants, because human milk is a poor source of vitamin D. If you are breastfeeding, give your infant a supplement of 400 IU of vitamin D every day.
• Older adults, because your skin doesn't make vitamin D when exposed to sunlight as efficiently as when you were young, and your kidneys are less able to convert vitamin D to its active form.
• People with dark skin, which has less ability to produce vitamin D from the sun.
• People with conditions that make it difficult to absorb nutrients from food, such as Crohn's disease, ulcerative colitis, and celiac disease.
• People who have obesity, because their body fat binds to some vitamin D and prevents it from getting into the blood.
• People who have had gastric bypass surgery, a type of weight loss surgery which creates a bypass of part of the small intestine. Since vitamin D is absorbed there, bypassing part of it makes it harder to absorb enough vitamin D.
• People with chronic kidney or liver disease, which can affect your ability to change vitamin D into a form your body can use.
• People who take medicines that affect vitamin D levels, including certain cholesterol, anti-seizure, steroid, and weight-loss medicines.

Talk with your provider if you are at risk for vitamin D deficiency. There is a blood test that can measure how much vitamin D is in your body.

Vitamin D deficiency can lead to a loss of bone density, which can contribute to osteoporosis and fractures (broken bones).

Severe vitamin D deficiency can also lead to other diseases:

• In children, it can cause rickets. Rickets is a rare disease that causes the bones to become soft and bend. African American infants and children are at higher risk of getting rickets.
• In adults, severe vitamin D deficiency leads to osteomalacia. Osteomalacia causes weak bones, bone pain, and muscle weakness.

There are a few foods that naturally have some vitamin D:

• Fatty fish such as salmon, tuna, and mackerel
• Beef liver
• Cheese
• Mushrooms
• Egg yolks

You can also get vitamin D from fortified foods. You can check the food labels to find out whether a food has vitamin D. Foods that often have added vitamin D include:

• Milk
• Breakfast cereals
• Orange juice
• Other dairy products, such as yogurt
• Soy drinks

Vitamin D is in many multivitamins. There are also vitamin D supplements, both in pills and in a liquid for babies.

If you have vitamin D deficiency, the treatment is with supplements. Check with your provider about how much you need to take, how often you need to take it, and how long you need to take it.

Getting too much vitamin D (known as vitamin D toxicity) can be harmful. Signs of toxicity include nausea and vomiting, poor appetite, constipation, weakness, and weight loss.

Very high levels of vitamin D can damage the kidneys. It also raises the level of calcium in your blood. High levels of blood calcium (hypercalcemia) can cause confusion, kidney failure, and irregular heartbeat (arrhythmia).

Most cases of vitamin D toxicity happen when someone overuses vitamin D supplements. You cannot get too much vitamin D from sun exposure because the skin limits the amount of vitamin D it makes.

Electrolytes are minerals that have an electric charge when they are dissolved in water or body fluids, including blood. The electric charge can be positive or negative. You have electrolytes in your blood, urine (pee), tissues, and other body fluids.

Electrolytes are important because they help:

• Balance the amount of water in your body
• Balance your body's acid/base (pH) level
• Move nutrients into your cells
• Move wastes out of your cells
• Support your muscle and nerve function
• Keep your heart rate and rhythm steady
• Keep your blood pressure stable
• Keep your bones and teeth healthy

The main electrolytes in your body include:

• Bicarbonate, which helps maintain the body's acid and base balance (pH). It also plays an important role in moving carbon dioxide through the bloodstream.
• Calcium, which helps make and keep bones and teeth strong.
• Chloride, which also helps control the amount of fluid in the body. In addition, it helps maintain healthy blood volume and blood pressure.
• Magnesium, which helps your muscles, nerves, and heart work properly. It also helps control blood pressure and blood glucose (blood sugar).
• Phosphate, which works together with calcium to build strong bones and teeth.
• Potassium, which helps your cells, heart, and muscles work properly.
• Sodium, which helps control the amount of fluid in the body. It also helps your nerves and muscles work properly.

You get these electrolytes from the foods you eat and the fluids you drink.

An electrolyte imbalance means that the level of one or more electrolytes in your body is too low or too high. It can happen when the amount of water in your body changes. The amount of water that you take in should equal the amount you lose. If something upsets this balance, you may have too little water (dehydration) or too much water (overhydration). Some of the more common reasons why you might have an imbalance of the water in your body include:

• Certain medicines
• Severe vomiting and/or diarrhea
• Heavy sweating
• Heart, liver or kidney problems
• Not drinking enough fluids, especially when doing intense exercise or when the weather is very hot
• Drinking too much water

The names of the different types of electrolyte imbalances are:

A test called an electrolyte panel can check the levels of your body's main electrolytes. A related test, the anion gap blood test, checks whether your electrolytes are out of balance or if your blood is too acidic or not acidic enough.

The treatment for an electrolyte imbalance depends on which electrolytes are out of balance, if there is too little or too many, and what is causing the imbalance. In minor cases, you may just need to make some changes to your diet. In other cases, you may need other treatments. For example:

• If you don't have enough of an electrolyte, you may get electrolyte replacement therapy. This involves giving you more of that electrolyte. It could be a medicine or supplement that you swallow or drink, or it may be given intravenously (by IV).
• If you have too much of an electrolyte, your provider may give you medicines or fluids (by mouth or by IV) to help remove that electrolyte from your body. In severe cases, you may need dialysis to filter out the electrolyte.