Five healthy habits to develop in your 20s and 30s

We talked to Fredericson, King and other Stanford Medicine experts on health throughout the lifespan to find out what habits people in their 20s and 30s should prioritize to set themselves up for long-term health. Their advice boiled down to five recommendations.

1. Build strength training into your weekly routine

Here’s something most people don’t realize: Your 20s and early 30s are when you hit peak bone mass and muscle strength. Think of it as your body’s baseline — the foundation you’ll build on (or lose from) for the rest of your life.

How do you make this foundation as strong as possible? Resistance training. This means any exercise where your muscles work against an external force, like dumbbells, resistance bands, weight machines or even your own body weight. Think squats, bicep curls, pushups, lunges or planks. Resistance training increases bone density, wards off muscle loss later in life and keeps your metabolism humming.

The current national recommendation is at least two strength training sessions per week. But here’s the part many people miss: to get stronger, you need to push yourself almost to the max.

“The key to really getting stronger is you have to exercise close to fatigue, to the point where you say, ‘I can do only one or two more reps,’” Fredericson explained. “If you’re not exercising to fatigue, you might maintain, but you’re not going to build new muscle.”

You don’t need to lift heavy weights. Lower weights with higher repetitions work just as well — if you push yourself to that fatigue point. A crucial point, especially for women who might be skeptical: Lifting weights won't make you bulky. Instead, it will build the crucial bone density and strength that protects you from osteoporosis and fractures decades later.

2. Prioritize consistent cardio exercise — and keep moving all day

Does that mean you need to start training for a marathon? Nope. The U.S. Department of Health and Human Services, which authorized the most recent national physical activity guidelines for Americans in 2018, recommends 150 minutes per week of moderate-intensity aerobic activity, 75 minutes per week of vigorous aerobic activity, or a comparable combination of both. But here’s the best part: Walking counts, and studies have shown it to be incredibly effective in boosting cardiovascular health.

“Walking is a wonderful activity that many people can do and enjoy,” King said. Recent research shows that aiming for at least 7,000 steps per day (not the oft-cited 10,000 steps) provides significant health benefits in multiple systems in your body. For even greater benefits, King recommends interval walking: Walk at your normal pace, then walk more briskly for a few minutes, then return to your regular pace.

Something else to remember: Sitting for more than eight hours a day is equivalent to smoking in terms of health risks, even if you exercise regularly.

“Even if you’re getting those exercise recommendations, if you’re sitting more than eight hours a day, it’s going to negate a lot of that,” Fredericson warned. Prolonged sitting reduces active energy expenditure and stops the activation of your skeletal muscles, leading to decreased blood flow. Over time, this affects your metabolism.  

The solution? Break up prolonged sitting with movement bursts. Get up every 30 minutes and walk around for three to five minutes, do some squats, jog in place, or go up and down a flight of stairs.

3. Eat for long-term health and energy

For many people in their 20s and 30s, eating well takes a backseat to convenience. You’re grabbing takeout between meetings, ordering late-night pizza with friends, or living on coffee and whatever’s quickest. It’s easy to think you can get away with it because you feel fine now. But the nutrition choices you make during these years are quietly setting up your metabolic and cardiovascular health for decades to come.

The CARDIA (Coronary Artery Risk Development in Young Adults) study, launched in the 1980s, has followed more than 5,000 young adults as they age. Over 35 years, it has shown that people who ate less fast food and those who followed a plant-based diet from ages 18 to 30 had a lower risk of cardiovascular disease and insulin resistance in middle age.

Your 20s and 30s are your opportunity to build nutritional habits that become second nature. The patterns you establish now — whether that’s cooking at home regularly, keeping healthy snacks on hand or learning to enjoy vegetables — will be far easier to maintain than habits you try to adopt later under the pressure of a health crisis.

“Focus on whole foods,” King said. “It doesn’t have to be complicated. I’m encouraged by the fact that the food industry is making eating healthier a lot easier than it used to be with things like grab-and-go fresh salads and healthier frozen options.”

Both Fredericson and King — as well as organizations like the American Heart Association — strongly advocate for the Mediterranean diet, which emphasizes plants, whole grains, healthy fats and lean proteins while remaining flexible. Research consistently shows this approach reduces inflammation — a key driver of chronic diseases from heart disease to Alzheimer’s.

Some key priorities for your 20s and 30s:

• Get enough protein: Aim for about 0.8 to 1.0 grams per kilogram of body weight — roughly 55 to 70 grams daily for a 150-pound person.
• Master the basics: Learn to fill half your plate with colorful fruits and vegetables, choose whole grains over refined carbohydrates, and limit ultra-processed foods high in added sugars and sodium.
• Hydrate intentionally: Aim for adequate water intake, especially if you’re active or drinking alcohol socially.
• Watch your alcohol intake: The suggested guidelines are no more than one drink per day for women and no more than two for men.

4. Establish good sleep hygiene

If you’re burning the candle at both ends in your 20s and 30s — whether for work, social life or both — you might think sleep is something you can skimp on now and make up for later. But chronic sleep deprivation during these years has lasting consequences for your physical and mental health.

“The sweet spot is usually greater than seven hours,” said Clete Kushida, MD, PhD, professor of psychiatry and behavioral sciences and chief and medical director of Stanford’s Division of Sleep Medicine.

This recommendation comes from a 2015 consensus statement from the American Academy of Sleep Medicine and the Sleep Research Society, which Kushida helped author after reviewing hundreds of studies on sleep and health.  

Research shows that people who consistently get less than seven hours of sleep per night have higher rates of obesity, diabetes and cardiovascular disease by middle age, even after accounting for other lifestyle factors.

Many young adults fall into a pattern of sleeping five or six hours on weeknights and “catching up” on weekends. But research shows you can’t fully compensate for chronic sleep deprivation with weekend recovery sleep. The metabolic and cognitive effects of sleep debt compound over time.

King notes that the optimal number of hours of sleep for peak performance and longevity can vary between people and that a wearable device can help you gauge what is best for your body.

It’s also not just about quantity. Sleep quality matters too. To improve both, Kushida recommends establishing consistent sleep habits, including a regular wake-up time (even on weekends), morning light exposure and pre-bedtime rituals to wind down (preferably without screens, alcohol or strenuous exercise).

If you’re consistently staying in bed for seven or eight hours of sleep but still feeling exhausted during the day, something’s wrong. 

“If you’re getting enough hours of sleep but still feeling sleepy, it means your sleep is probably fragmented or you’re not getting enough REM or deep sleep,” Kushida said. “It would be a good idea to consult a sleep specialist.”

Another alternative is to try out one of the current wearable watches or similar devices now on the market that have become increasingly accurate in measuring sleep stages and can provide further information on actual sleep patterns, adds King.

You might have an undiagnosed sleep disorder such as obstructive sleep apnea (which affects young adults more than many realize, especially those who are overweight), restless leg syndrome or insomnia. More than 50 million Americans have sleep disorders, and most are undiagnosed.

5. Manage stress like it’s your job

Your 20s and 30s can be some of the most stressful decades of your life. You’re navigating career pressures, relationship decisions and financial uncertainty, and maybe you’re starting a family. It’s tempting to tell yourself you’ll deal with the stress later, once things calm down. But chronic stress during these years doesn’t just make you feel overwhelmed — it has measurable effects on your body that accumulate.

“It’s important to manage stress or stress will manage you,” said David Spiegel, the Jack, Lulu, and Sam Willson Professor in Medicine; associate chair of Psychiatry and Behavioral Sciences; and director of the Stanford Center on Stress and Health.

When you’re stressed, your body responds as if you’re facing a physical threat. Your heart rate increases, blood pressure rises and stress hormones like cortisol flood your system. In short bursts, this response is normal and even helpful. But when stress becomes chronic, these physiological changes can damage your health.

Luckily, Spiegel says that you can train your body to manage stress better. His research focuses on techniques that work “from the body up rather than the head down.”

“We tend to think that the only way to manage the physiology of stress is to solve the problem that is causing you stress,” he says. “But my research has shown that you should start out by calming your body, then you’ll be able to think through better what the stressors are.”

Spiegel recommends that young adults learn stress reduction techniques like meditation, deep breathing or self-hypnosis. Spiegel’s research on self-hypnosis found that people who learned these techniques experienced significantly less pain and stress, and the benefits lasted for years. He has developed a mobile app, Reveri, that teaches these skills.

He also underscores that other areas of health are linked to mental health. Eating healthy, exercising, avoiding drugs or excessive alcohol, and getting enough sleep can all help you manage stress and anxiety better.

If you’re feeling more than stressed out — helpless, hopeless or worthless — Spiegel recommends seeking professional help to manage your psychiatric health.

Luckily, with help — and with practices like those that Spiegel teaches — you have more control over stress than you might think. If you start building those skills now, you’ll have them when you need them throughout life. The earlier you start managing stress, the better prepared you will be for whatever challenges come your way.

This article is part of a series on healthy habits for different age groups. Keep reading about building healthy habits for longevity in your 40s and 50s and healthy habits to maintain independence in your 60s and 70s.