Self-care is based on lifestyle medicine—an evidence-based approach to disease prevention and treatment that focuses on adopting healthy habits. It doesn’t replace traditional medicine, but it is a powerful complement to it.

Americans are far less healthy than they could be. Six out of every 10 live with at least one chronic disease, according to the CDC. Four in 10 people have two or more conditions. Chronic conditions like heart disease, cancer, stroke, and diabetes exact a heavy toll on our collective health and productivity.

In 2018, researchers from Harvard’s T.H. Chan School of Public Health analyzed data from the CDC and two long-term population studies—the Nurses’ Health Study and the Health Professionals Follow-up Study. They found that people who practiced five specific lifestyle habits dramatically reduced their risks of heart disease and cancer, compared with those who did none of these things. The healthy participants

• ate a diet high in fruits and vegetables, whole grains, and unsaturated fatty acids, and low in red and processed meats, sugary drinks, trans fats, and sodium

• did not smoke

• got at least three-and-a-half hours of moderate-to vigorous physical activity each week

• drank only moderate amounts of alcohol (no more than one drink per day for women, and two drinks or less per day for men)

• maintained a healthy body mass index (BMI) in the range of 18.5 to 24.9.

How effective were these measures?

The researchers found that practicing all five habits from age 50 onward extended life by more than a decade compared with practicing none of them. Women who didn’t adopt any of the habits lived on average to age 79, while those who did all five lived to 93. Similarly, men who did not practice these five habits lived to 75 on average, while those that did lived to nearly 88.

When it comes to self-care, habits that foster a healthy body are a good place to start. But one thing scientists have learned over time is that the mind and body are inextricably linked. Thoughts and emotions influence health in many ways. For example, stressful events make your blood pressure spike. Depression lowers your tolerance for pain, making pain feel worse. And loneliness now appears to be a cause of premature death. These are just three examples among many.

That means that any program for true self-care must go beyond these five habits, but they are the foundation of creating wellness.