Erectile dysfunction — the inability to get and keep an erection firm enough for sex — can be an early warning sign of current or future heart problems. Likewise, if you have heart disease, getting the right treatment might help with erectile dysfunction. Understand the connection and what you can do about it.

In the past, the buildup of plaques in the arteries of your body (atherosclerosis) was believed to be the reason why erectile dysfunction often precedes heart problems. The idea was that plaque buildup reduces blood flow in the penis, making an erection difficult.

However, experts now believe that erectile dysfunction preceding heart problems is more often due to the dysfunction of the inner lining of the blood vessels (endothelium) and smooth muscle. Endothelial dysfunction causes inadequate blood supply to the heart and impaired blood flow to the penis, and aids in the development of atherosclerosis.

Erectile dysfunction does not always indicate an underlying heart problem. However, research suggests that men with erectile dysfunction who have no obvious cause, such as trauma, and who have no symptoms of heart problems should be screened for heart disease before starting any treatment.

Besides sharing a common disease process, erectile dysfunction and heart disease also share many risk factors, including:

• Diabetes. Men who have diabetes are at high risk of erectile dysfunction and heart disease.
• Tobacco use. Smoking increases your risk of developing vascular disease and can cause erectile dysfunction.
• Alcohol use. Drinking too much alcohol can cause heart disease and might contribute to other causes of heart disease, such as high blood pressure or abnormal cholesterol. Alcohol also impairs erections.
• High blood pressure. Over time, high blood pressure damages the lining of your arteries and accelerates the process of vascular disease. Certain high blood pressure medications, such as thiazide diuretics, can also affect sexual function.
• High cholesterol. A high level of low-density lipoprotein (LDL, or "bad") cholesterol can lead to atherosclerosis.
• Age. As you get older, erections might take longer to develop and might not be as firm. The younger you are, the more likely that erectile dysfunction signals a risk of heart disease. Men younger than 50 are at especially high risk.
• Obesity. Excess weight typically worsens other risk factors for heart disease.
• Low testosterone. Men with low testosterone have higher rates of erectile dysfunction and cardiovascular disease than do men with normal testosterone levels.

If your doctor thinks you might be at risk of heart disease, consider making lifestyle changes. Any lifestyle change that improves heart health improves penis health, too. Increase your physical activity, maintain a healthy weight, stop smoking and drink alcohol only in moderation — or not at all. More-serious signs and symptoms of heart disease could lead to further tests or treatment.

If you have both erectile dysfunction and heart disease, talk to your doctor about treatment options. If you take certain heart medications, especially nitrates, it is not safe to use many of the medications used to treat erectile dysfunction.