The number of candles on your birthday cake may mark your chronological age, but it doesn’t necessarily say much about how you feel. Your biological age, or how your body functions at the cellular and molecular level, isn’t just determined by time, according to William W. Li, M.D., an internationally renowned physician, scientist, and author of The New York Times bestseller Eat to Beat Disease: The New Science of How Your Body Can Heal Itself. Instead, it’s shaped by daily diet and lifestyle choices.
Habits that drive inflammation—like smoking, drinking alcohol, being sedentary, and eating nutrient-poor foods—accelerate cellular aging. The faster this happens, the more quickly we see the signs of aging, such as wrinkled skin, shrinking muscles, low energy, and overall frailty, Li explains. Importantly, beneath the surface, these habits impact how well the body functions on every level. “Chronic inflammation is closely tied to the development of most of the chronic diseases that lead to shortened lifespan, including heart disease, cancer, metabolic diseases like diabetes, and dementia,” says Li.
On the flipside, a life rich in movement, nutrients, and adequate rest can help slow the impact of time on the body’s cells and systems, according to holistic and functional registered dietitian Jenna Volpe, R.D.N., L.D., C.L.T., founder of Whole-istic Living. “The culmination of good day-to-day lifestyle habits and food choices can really slow down the rate at which we age and support longevity,” she says.
Ahead, a closer look at the most effective ways you can support longevity, from the inside out.
- ABOUT OUR EXPERTS: William W. Li, M.D., is an internationally renowned physician, scientist, and author of The New York Times bestseller Eat to Beat Disease: The New Science of How Your Body Can Heal Itself. Jenna Volpe, R.D.N., L.D., C.L.T., is a holistic and functional registered dietitian and founder of Whole-istic Living.
1. Prioritize Stress Management
Stress is like salt: A little enhances the flavor of life, but too much is a recipe for disaster, especially if it goes unchecked for long periods.
“Stress activates our sympathetic ‘fight or flight’ nervous system response, which releases the stress hormone, cortisol, into our bloodstream,” says Li. In small doses, cortisol can be helpful, he says. The short-lived whoosh you get during high-intensity interval training (HIIT) or before a work presentation, for example, helps kickstart exercise recovery and dial in focus. “Chronic stress, however, causes chronic inflammation, which wears down the body’s defenses,” he explains.
Over time, high levels of cortisol damage the lining of our blood vessels and increase our blood pressure, affecting blood flow. This wreaks havoc on circulation, which impacts major organs like the heart, the brain, and the kidneys, and ultimately can increase the risk of serious disease, he says. Not to mention, excess cortisol also impacts the integrity of the gut lining, suppresses the immune system, and destabilizes blood sugar.
Read More: Why You Should Prioritize Adrenal Health During Times Of Stress
Chronic stress can also lead to depression and anxiety, which makes it harder to stick to lifestyle habits that support longevity. “This can contribute to erosion of our health defenses,” Li says.
The Fix: In today’s world, scrolling is one of the most common instigators of the stress response, according to board-certified internist Jacob Teitelbaum, M.D., author of the best-selling From Fatigued to Fantastic. Social media regularly triggers feelings of comparison and doomsday thinking, which both turn up the volume on stress, he says.
Feelings of irritability, inadequacy, and overwhelm are all signs it’s time to unplug. Teitelbaum also recommends proactively unfollowing or muting accounts that consistently make you feel less-than.
Boundaries offline are important, too. “Learn to say ‘no’ to things that feel bad,” Teitelbaum suggests. Of course, adding in positive experiences and practices is just as important as nixing things that drain you. Deep breathing, meditating, grounding, keeping a gratitude journal, connecting with community, and moving regularly also combat stress, per the CDC.
2. Consume Enough Protein
Muscle mass isn’t just for your reflection in the mirror. The metabolically active tissue helps you walk, climb stairs, carry groceries, and even sit and stand up from the toilet. It also pads and protects your joints, supports a healthy weight, and can lower your risk of certain chronic diseases.
The catch: Starting as early as age 30, we begin to lose nearly one percent of our muscle mass each year due to a combination of a drop in the sex hormones, cellular aging, and chronic low-grade inflammation, says Li.
In some people, especially those with poor nutrition or inactivity, this muscle loss can lead to a serious condition called sarcopenia. “We often see this progressive loss of muscle in frail older adults—and it significantly raises the risk of falls, fractures, and other injuries,” he says.
The Fix: One key to minimizing muscle mass decline is adequate protein intake. “Proteins are made of building blocks called amino acids,” explains Li. “When you eat protein, your body harvests these amino acids for building and maintaining muscles, as well as nerves, blood cells, brain cells, and more.”
Of the 20 amino acids, each has a unique function in the body. Leucine, isoleucine, and valine—known as branched-chain amino acids (BCAAs)—in particular, are essential for muscle preservation and growth, says Volpe. These are abundant in animal foods like eggs, chicken, fish, and dairy, though they can also be found in soy, legumes, and BCAA supplements.
If living a long, healthy life is your North Star, Volpe suggests aiming for a protein-rich diet that includes both animal and plant sources to get all those essential amino acids in. Getting the full spectrum of aminos—and a daily protein intake of 0.54 to 0.68 grams per pound of body weight—will help protect your muscles as you age, while supporting your brain, gut, and system overall, she says. When running low, turn to convenient protein powders, bars, and ready-to-drink shakes.
3. Eat A Diet Rich in Healthy Fats
Your brain soaks up healthy fats like a sponge soaks up suds. In particular, it gulps down omega-3 fatty acids, which help maintain healthy circulation and inflammation levels, which support brain function, says Li. The benefits of sound blood flow and healthy inflammation levels don’t stop at mental clarity, either; they support heart, kidney, and joint health, too, he adds.
Read More: 6 Signs You Have Inflammation
Omega-3s may also play a role in gut health. “They’ve been shown to positively influence the gut microbiome by enhancing immune function,” Li says. More good news for long-haul wellness seekers!
The Fix: “Counting grams of fat would be a very annoying way to spend the rest of one’s life,” says Teitelbaum. Instead, focus on consistently incorporating omega-3-rich fish like salmon, sardines, or herring at least twice a week, and interspersing plant-based sources like chia seeds, flax, and walnuts into your diet, he says. When possible, Teitelbaum also suggests choosing grass-fed beef over grain-fed. “Grass-fed beef contains higher omega-3s and is less inflammatory than grain-fed,” he says. Taking a daily omega-3 supplement is an easy way to ensure you’re getting your fill, too.
4. Don’t Snooze On Sleep
Sleep isn’t a luxury, but a non-negotiable pillar of healthy aging. “Poor quality or insufficient sleep quickly leads to deteriorating health,” says Li.
The links between consistent, restorative sleep and longevity are plentiful. Research has shown that sleep supports everything from immune regulation and hormone balance to cognitive function and gut health, Li says. Studies also show that getting enough high-quality sleep reduces levels of oxidative stress, which directly causes cellular aging.
“Getting a minimum of eight hours of high-quality sleep each night is critical for optimizing growth hormone release,” adds Teitelbaum. Growth hormone supports tissue repair, muscle maintenance, and metabolic health—so, when sleep is compromised, exercise recovery, muscle mass, and weight can be, too, he says.
The Fix: Your first step towards optimizing sleep is to “cut out things you don’t enjoy in life and use that time for sleep,” according to Teitelbaum. After all, adding in any new habit is tricky if you don’t first make time for it by cutting back on late-night scrolling or social obligations that interfere with your wind-down routine, he says.
Keeping your room cool and quiet, turning off electronics at least 30 minutes before bed, and avoiding large meals, alcohol, and caffeine in the evening can also support sound sleep quality and quantity, the CDC says.
If you’ve implemented the classic sleep hygiene hacks but still struggle to conk out, Volpe suggests talking to your healthcare provider about supplementation. “Magnesium glycinate can be a wonderful supplement for stress and sleep quality,” she says. “Ashwagandha, an Ayurvedic adaptogen, has also been shown to help improve sleep quality.” Finally, certain sedative or nervine herbs such as chamomile and lavender can help relax the nervous system and improve sleep in many cases, she adds.
5. Pay Attention To Gut Health
Of the inner influences on how vibrant (or not) you look as the years fly by, your gut is one of the biggest. “There’s a strong correlation between a healthy gut and healthy skin,” says Volpe. This relationship is known as the gut-skin axis, and it refers to how the health of your gut microbiome influences inflammation, immune function, and skin appearance.
Essentially, the healthier your gut microbiome—meaning, the greater the diversity of “healthy” bacteria—the less likely you are to have noticeable signs of aging and other skin disorders. Meanwhile, the more “bad” bacteria in the gut, the faster an individual ages. In fact, a 2024 review in Frontiers in Physiology found that changes in the gut microbiome negatively impact the skin’s barrier function, resulting in decreased moisture retention and increased vulnerability to infection.
Read More: The 8 Most Gut-Friendly Foods On The Planet
Notably, the gut speaks to your brain, too. In fact, an estimated 95 percent of serotonin, the happiness hormone, is made in the gut, and research has found that people with depression often have lower levels of certain bacteria. Depressive episodes are linked with accelerated aging, and poor mental health can make longevity-friendly habits feel less tenable, which further highlights the benefit of gut health for healthspan seekers.
The Fix: The gut microbiome is nourished by probiotics, fiber, water, protein, and vitamins and minerals, says Volpe. Meanwhile, it’s depleted by refined sugars, trans fats, artificial flavors, and preservatives.
With that, Volpe recommends aiming for 25 to 30 grams of fiber per day, which can be obtained by eating colorful fruits and vegetables (and taking fiber supplements, if necessary). She also recommends consuming two to three servings of fermented foods (kimchi, kefir, sauerkraut, etc.) daily, or taking a probiotic supplement.