Dr. Mehmet Oz
Who did Dr. Oz count on for answers to questions he couldn't figure out in medical school? His father-in-law! Dr. Gerald Lemole, Lisa Oz's father, talks with Dr. Oz and Lisa about the importance of getting enough vitamin D.

Dr. Lemole says the importance of vitamin D is highly underrated. It's not only good for bone health, but has also been correlated to improving a host of illnesses, including colon cancer, inflammation, multiple sclerosis, seasonal disorders and depression. In addition, Dr. Lemole says many older people lose their balance not because of their age, but because they have low levels of vitamin D, which helps regulate muscle and balance.

Dr. Lemole says that although you can take vitamin D as an oral supplement, the best way for it to be absorbed is by getting some sun exposure. "Everybody is afraid of the sun—everyone uses hats and sunscreen to cover up everything, and we don't really get out in the sun," Dr. Lemole says. Because of this, people are getting less vitamin D, he says. While Dr. Lemole doesn't recommend spending a long time bathing in the sun, 15 minutes a day will get you the vitamin D levels that are recommended, he says.

Dr. Lemole also says that every person is different and may require different levels of vitamin D depending on how much you take, how your body absorbs it and what you eat. He also stresses that it helps to improve the immune system as well and works with more than a thousand genes in the body.