More to Sibling Rivalry: Greater Health Concerns Among First-borns


Do you have brothers or sisters? If so, you know all about sibling rivalry. At some point along the way, you probably realized that the oldest usually finds a way to come out on top.

While being the first-born may have its perks, when it comes to your health, it also may have some big drawbacks, at least according to one new study. I sat down with NewsRadio 1080 KRLD to talk more about health concerns among siblings.

Q:  It’s surprising to learn that first-borns may be more susceptible to certain diseases than younger siblings. What are those diseases?

Not only first-borns, but only children as well are at a greater risk for developing metabolic or cardiovascular disease.

A study out of New Zealand found that first-borns had more difficulty absorbing sugars into the body and had higher blood pressure. This may translate into a greater risk for type 2 diabetes, heart attack, stroke, coronary artery disease and more much later in their lives.

The good news for first-borns is that they study also found that they tend to be taller and slimmer than their later-born counterparts.


Q:  How did researchers determine that first-borns had a heightened risk for these diseases, and what do they attribute it to?

The study measured fasting lipid and hormonal profiles, height, weight and body composition in 85 healthy children between the ages of 4 and 11-years-old.

The reason they looked at children because puberty and adult lifestyle can heavily impact insulin sensitivity and blood pressure. The result was a 21 percent drop in insulin sensitivity and a 4 mmHg increase in blood pressure.

Researchers believe that the reason for these increased risk factors is due to physical changes in a mother’s uterus between their first pregnancy and later pregnancies. The thought is that these changes can affect the flow of nutrients from the mother to the fetus. The flow increases later in the pregnancy too.

Researchers caution that more work needs to be done to translate how these increased risk factors due to birth order actually translate into these conditions as adults.

Q:  What are the practical implications of this study, or are there any? Is this just research adding to a body of knowledge about these conditions?

For public health officials, these results are alarming because there is a rise in only children in many countries.

This means that a larger portion of their population are at a greater risk for developing metabolic/cardiovascular conditions (like China’s one-child policy). It’s important for doctors to be aware of this and be ready to talk to their patients about it if questions arise.

It’s also important to keep in mind that this finding is just one of the many factors that increase risk for these diseases and probably aren’t even the most important. The most important should be a good diet, avoiding smoking and exercising.

If this study is to be believed, these may be even more important for first-borns.

About the author

David Winter, MD
More articles

David Winter, MD, is an internal medicine physician on the medical staff at Baylor Scott & White Signature Medicine – Tom Landry.

Leave a Reply

More to Sibling Rivalry: Greater Health Concerns Among First-borns