Are your kids giving you heart disease?
A study published in the journal Circulation asked this fascinating question: does the number of children you have increase your risk for heart disease? Researchers Lawlor et al studied 4286 women and 4252 men from Great Britain, all aged 60-79, and assessed their risk factors for coronary heart disease. By including both women and men in this study, they hoped to reveal whether lifestyle factors (affecting both sexes) or biological factors associated with pregnancy (which wouldn’t affect men) might play a role.
As it turns out, the prevalence of risk factors for coronary heart disease was lowest among both sexes with two children. However, each additional child increased the risk of coronary heart disease by 30% for women and 12% for men! When obesity and metabolic risk factors (such as diabetes) were taken into account, there was still an unexplained association between number of children and heart disease in women.
What specific risk factors were found to be increased among those with more than two children? In women, number of children was associated with decreased HDL (good) cholesterol and increased triglycerides and diabetes. A greater waist-to-hip ratio and body mass index was found among both women and men.
From this data, the authors concluded that lifestyle factors associated with having large families may contribute to obesity and coronary heart disease in both sexes. In women, however, issues other than lifestyle appear to be involved. One possible explanation is that multiple pregnancies would decrease a woman’s lifetime exposure to estrogen, which could factor into coronary heart disease. Another explanation is that multiple pregnancies could cause permanent diabetes-like changes in the way the body handles sugars and fats. This explanation is supported by earlier studies, which have established a relationship between number of children and obesity, low HDL (good) cholesterol, insulin resistance, and carotid plaques in older women. If, after reading this article, you are concerned that your kids may be giving you heart disease, don’t worry - talk to your doctor about making lifestyle changes as a family that will help everyone’s heart. 
Picture taken from heartzine.com on December 14, 2008