Second Opinion with Joan Lunden - Season 7

Vitamin D is a fat-soluble vitamin. Fat-soluble vitamins are stored in the body's fatty tissue. Vitamin D helps the body absorb calcium. Calcium and phosphate are two minerals that are essential for normal bone formation. Throughout childhood, your body uses these minerals to produce bones. If you do not get enough calcium, or if your body does not absorb enough calcium from your diet, bone production and bone tissues may suffer. Vitamin D deficiency can lead to osteoporosis in adults or rickets in children.

Celiac disease is a digestive disease that damages the small intestine and interferes with absorption of nutrients from food. People who have celiac disease cannot tolerate gluten, a protein in wheat, rye and barley. Gluten is found mainly in foods but may also be found in everyday products such as medicines, vitamins and lip balms.

Multiple sclerosis (MS) is a chronic, unpredictable disease of the central nervous system (the brain, optic nerves, and spinal cord). It is thought to be an autoimmune disorder. This means the immune system incorrectly attacks the person's healthy tissue.

Bipolar disorder, formerly known as manic-depressive illness, is a brain and behavior disorder characterized by severe shifts in a person's mood and energy, making it difficult for the person to function. More than 5.7 million American adults or 2.6 percent of the population age 18 or older in any given year have bipolar disorder. The condition typically starts in late adolescence or early adulthood, although it can show up in children and in older adults. People often live with the disorder without having it properly diagnosed and treated.

Your cancer treatment is over, but the treatments that may have saved your life may also continue to cause side effects. As more people are living longer after cancer treatment, more is becoming known about late side effects of cancer treatment. Find out all you can about late effects of cancer treatment and use this information to help manage your health.

Treatment for breast cancer can be overwhelming, both physically and emotionally. While having reconstructive surgery is a personal choice, knowing your options can help you better prepare for the future.

African-American adults are less likely to be diagnosed with coronary heart disease, but they are more likely to die from heart disease. Knowing what steps can be taken by patients, providers and the community to improve the quality of cardiac care for all American is critical to an effective and efficient health care system.

A mammogram is a special type of X-ray of the breasts. Mammograms can show tumors long before they are big enough for you or your health care provider to feel. They are recommended for women who have symptoms of breast cancer or who have a high risk of the disease. You and your health care provider should discuss when to start having mammograms and how often to get one.

Americans experience loss of bowel control (fecal incontinence). It affects people of all ages, and can be devastating to a person's self esteem and family life. Knowing what treatments are available can improve bowel control and makes incontinence easier to manage.

Heart failure is a condition in which the heart can't pump enough blood throughout the body. Heart failure does not mean that your heart has stopped or is about to stop working. It means that your heart is not able to pump blood the way it should.

Cervical cancer is caused by several types of a virus called human papillomaviruses (HPV). The virus spreads through sexual contact. Most women's bodies are able to fight HPV infection. But sometimes the virus leads to cancer. You are at higher risk if you smoke, have many children, use birth control pills for a long time, or have HIV infection.

Your spinal cord is a bundle of nerves that runs down the middle of your back. It carries signals back and forth between your body and your brain. A spinal cord injury disrupts the signals. Spinal cord injuries usually begin with a blow that fractures or dislocates your vertebrae, the bone disks that make up your spine. Most injuries don't cut through your spinal cord. Instead, they cause damage when pieces of vertebrae tear into cord tissue or press down on the nerve parts that carry signals.

Dizziness is a term that is often used to describe two different symptoms: lightheadedness and vertigo. Light-headedness is a feeling like you might faint. Vertigo is a feeling that you are spinning or moving, or that the the world is spinning around you. Most causes of dizziness are not serious and either quickly get better on their own or are easily treated.