Heart disease is on the rise in younger adults. A cardiologist says prevention needs to start sooner.

• A cardiologist said we should think of heart health like retirement savings — start planning early.
• More millennials are facing heart disease, but changing your lifestyle can make a big difference.
• Protect your heart with habits like regular exercise, stress reduction, and increased fiber intake.

You wouldn't wait until your 50s to start saving for retirement — so why wait until your heart is already at risk to start protecting it?

Heart disease is spiking among younger people, in part because people in their 20s, 30s, and 40s are procrastinating on their health, according to Dr. Sadiya Khan.

Khan, a professor of cardiovascular epidemiology at Northwestern University, told Business Insider that changes to your diet and exercise habits now can pay big dividends as you age.

"You can't just become older and then hope to make all these changes," she said.

The earlier you understand your heart health, the better equipped you are to make healthy decisions for future you.

Your heart may be aging too quickly

Right now, most of us are behind in our investments to our cardiovascular health. The average American's heart is 4 to 7 years older than their calendar age, according to Khan's research.

"All of us are naturally driven to procrastinate," she said. "You try to worry about the things that are immediately in front of you, and it's harder to prioritize and give as much attention to something that is a long-term consequence.

An online tool, developed by Khan and her team, helps forecast a person's risk of heart attack or stroke over the next 30 years by illustrating how they stack up to their peers. It shows their percentile rank for heart health: in other words, out of 100 people the same age and sex, how many have a higher or lower risk of cardiovascular disease.

Khan said the new tool uniquely uses percentiles to help people manage their health by understanding their risk and making changes if needed. Patients can then prioritize which habits provide the best bang for their buck in terms of health benefits, starting with what Khan recommends most.

How to invest in your heart health now

Khan said a big challenge with heart health is that it can be highly individualized. All the factors involved — diet, exercise habits, genetics, and stress — can vary widely from person to person.

"It's not going to be a one-size-fits-all," she said. "It's this overarching goal that we need to personalize how we communicate risk and how we can share that information in a way that works for each patient."

That makes it hard to recommend a specific game plan to boost everyone's heart health. However, there are a few strategies that can pay off for most people.

• Stop smoking. It may seem obvious, but if you're a smoker even occasionally, quitting is one of the most effective ways you can reduce heart health risks (and yes, smoking cannabis is bad for your heart, too).
• Get your steps in. Exercise helps strengthen the heart and stave off age-related disease, and most of us don't get enough. Walking an extra 500 steps a day can help start building better fitness from the ground up. Short bursts of high-intensity movement quickly add up for better health.
• Lift weights. Strength training is increasingly linked to better longevity, and movements like squats and deadlifts or at-home exercises like push-ups or wall sits can support a strong heart.
• Eat more beans. Most of us could benefit from eating more nutrients like fiber that protect heart health. Affordable foods like whole grains and beans offer protein, fiber, and nutrients to fuel better heart health. Plant-based whole foods also help to keep you full, making it easier to cut back on sweets and processed foods that can be hard on your heart.
• Take a tai chi break. It's no secret that stress can be harmful, and over time, it can take a major toll on your heart. Relaxing habits like spending time outdoors and doing yoga or tai chi help to lower your blood pressure and reduce cardiovascular strain. Getting enough quality, consistent sleep is crucial, too.

For best results, try to make small, sustainable changes that you can keep up over time.

"It depends on what works for you and what you are able to stick with," Khan said. "They all matter, but you don't also need to do it all at once."