Your health: Potential benefit of delaying having kids

Surprise benefit

Fathers who delay having children until they're almost 40 may be passing on the benefit of longer lives to their offspring.

The Washington Post reports that in a study in the Proceedings of the National Academy of Sciences children of older fathers, those in their late 30s to early 50s, inherit longer telomeres, caps at the end of the chromosomes that protect them from degeneration.

According to the study, longer telomeres seem to promote slower aging and may mean a longer life span for these children.

Previous research has shown that the older a man is when he reproduces, the more likely the children are to carry spontaneously arising mutations, which can produce disorders like autism. The new study suggests late fatherhood isn't all risk, said Dan Eisenberg, a study author and doctoral student at Northwestern University.

Checking out colon

Are you at that age, such as 50, when a colonoscopy is recommended? A few things to consider, according to the Harvard Medical School newsletter.

The benefits: Colon cancer is the fourth most common cancer in the United States and the second leading cause of cancer death. The risk of developing colon cancer rises at age 50, the age at which guidelines recommend screening begin for most people.

The risks: Colonoscopy requires a thorough bowel cleansing with a laxative the day before the test. For the test, the patient is sedated, the colon inflated with air or carbon dioxide, and a thin, tubelike instrument with a light and a lens for viewing as well as a tool to remove tissue for biopsy — is inserted into the rectum and passed through the entire colon.

The likelihood of a false-negative test: Colonoscopy is estimated to miss about 5% of colon cancers, most of them “upstream,” in the the colon.

The alternatives: A test for blood in the stool can detect colon cancer at an early stage, and is supposed to be done every year. Sigmoidoscopy is similar to colonoscopy, but requires far less bowel cleansing; it is recommended every five years, usually in conjunction with annual stool tests.

Double-contrast barium enemas give a view of the entire colon, require cleansing prep, but not sedation. These miss more polyps than colonoscopy and involve radiation exposure. CT scans of the colon require the cleansing prep and inflation of the colon, but not sedation. The scans also involve radiation.

Best advice is to talk things over and wieigh options with your doctor.