7 Habits That Impact Health by Your Mid-30s
Published on January 12, 2026
Next up video playing in 10 seconds
7 Habits That Impact Health by Your Mid-30s
Learn what lifestyle habits impact your biological age and long-term health by your mid-30s.
Note: While research on alcohol is evolving, the Centers for Disease Control and Prevention says drinking less or not at all is better for your health.
The cumulative effects of unhealthy habits may kick in sooner than you’d like to think. A newer study suggests that habits such as smoking, drinking, and being sedentary can start aging you as early as your mid-thirties. (The study followed more than 300 people for 30 years to understand the cumulative effects of these habits.)
“Your habits of today decide your tomorrow,” says Ankur S. Patel, MD, a board-certified geriatrician based in Moorestown, New Jersey, and the president of Inspira Living Independently for Elders, a program that ensures older adults can live independently at home for as long as possible.
Research on lifestyle habits distinguishes between chronological age (how old you are in years) and biological age (a measure of your body’s health and function). Lifestyle habits and genetics can result in a biological age that’s significantly older than chronological age, and vice versa.
The good news is you have a lot more control over how you age than you might think. While genetics account for about 15 to 25 percent of the effects of aging on your body, the other 75 to 85 percent is lifestyle.
To keep your chronological and biological age in sync, avoid the following habits.
1. Smoking
You’re unlikely to develop diseases such as emphysema or lung cancer due to smoking as early as your thirties, but smoking in younger adulthood lays the groundwork for future issues. “Just because you're not having symptoms doesn't give us the reassurance that there isn't something happening at a cellular level,” says Pamila Brar, MD, the medical director of the longevity program and a senior associate consultant in the department of internal medicine at the Mayo Clinic in Jacksonville, Florida.
Smoking causes cellular changes in your body, such as increased system-wide inflammation and oxidative stress, both of which contribute to chronic health conditions that are more common with age, including heart disease, stroke, and type 2 diabetes.
Smoking also disrupts proteins and lipids (fats) in the skin barrier (the outermost layer of the skin), accelerating wrinkling and other signs of skin aging, such as pigmentation. Research in 52 men with an average age of their mid-thirties found that those who smoked (roughly 28 men) showed greater signs of skin aging than those who had never smoked (about 24 men), as measured by the density of their skin and the surface area of their nasolabial folds (also called “smile lines”).
Your safest approach is to never start a smoking or vaping habit. If you do use tobacco, try to quit. “If you stop, at least for many people, those negative consequences are greatly diminished, or can even be completely overcome,” adds Matt Kaeberlein, PhD, a longevity researcher in Seattle and the CEO of Optispan, a health-span technology company. Indeed, quitting smoking can add as many as 10 years to your life expectancy.
2. Too Much Alcohol
Young adults who drink even small amounts of alcohol may face a higher risk for age-related concerns like high blood pressure (hypertension), stroke, heart disease, liver disease, and some cancers later in life.
While blood tests may not reveal signs of alcohol-related liver damage in your mid-thirties, there may be genetic changes happening that set you up for alcohol-related health problems down the road, Dr. Brar says. For example, research in twins suggests that alcohol use triggers a change in DNA that may turn on or off certain genes that play a role in your likelihood of developing chronic disease.
Alcohol is also dehydrating, which can dry out and damage your skin over time, making you look older than you are, says Rehan Karim, DO, a board-certified dermatologist with U.S. Dermatology Partners in Dallas.
It’s best to skip alcohol altogether. But that’s not realistic for everyone. If you decide to drink, try to keep it moderate. Most health organizations generally define that as no more than one drink per day for women or two drinks per day for men.
3. Lack of Exercise
Physical inactivity has a number of potential risks for your overall health and how well you age. Too little exercise sets you up for muscle and bone weakness, which increases your risk of developing osteoporosis later in life, Dr. Kaeberlein says.
A sedentary lifestyle can also contribute to older-looking skin in your mid-thirties because it reduces the amount of nutrient-rich blood that might otherwise be delivered to your skin during exercise, Dr. Karim says.
Physical inactivity can also lead to hidden changes in body composition. You might not necessarily notice a lack of muscle mass by your mid-thirties, especially if you’re still at a healthy weight and feeling fit and strong. But if a healthcare provider were to measure your muscle mass and visceral fat, you may have more body fat than is ideal for your height and weight, which can speed up muscle loss and increase your risk of life-threatening chronic conditions, Brar says.
Dr. Patel recommends breaking exercise into manageable chunks of 30 minutes of physical activity several times throughout the week. Find a form of physical activity that you enjoy, like playing a team sport, gardening, walking, or swimming, he says. And be sure to get at least two full-body strength training workouts per week.
4. Too Much Sun
The ultraviolet (UV) radiation that comes from the sun is one of the major causes of skin damage that can prematurely age your appearance, Karim says.
There are two forms of UV radiation: UVA and UVB. “UVA gets into the deeper parts of our skin that break down our collagen or elastin, which are structural proteins that normally keep skin firm and elastic,” Karim says. When collagen and elastin start to break down — which can happen as early as your mid-thirties — your skin can begin to wrinkle, sag, and lose firmness. UVB, on the other hand, leads to sunburns, inflammation, and other damage to the top layer of the skin and increases the risk of skin cancer.
The best line of defense against the skin-aging effects of UVA and UVB radiation is to wear sunscreen daily. It’s also worth investing in sun-protective clothing, hats, and sunglasses to further shield your skin from harmful UV rays, Karim says. Look for apparel with an ultraviolet protection factor (UPF, a measurement of how much UV radiation can penetrate the fabric) of 50 or above, which indicates the clothing blocks at least 98 percent of the sun’s rays. Similarly, choose sunglasses with 100 percent UV protection.
5. Poor Sleep
Consistently getting insufficient or poor quality sleep is associated with a greater risk of diabetes, high blood pressure, and obesity — conditions typically associated with aging. Rates of these chronic conditions have been steadily increasing in young adults ages 18 to 34 since 2015. This trend is concerning because sleep deprivation doesn’t just increase disease risk, but also accelerates aging at the cellular level.
“Over years or decades, inadequate sleep will accelerate biological aging,” Kaeberlein says. Research shows poor sleep is linked to cellular and genetic changes that reflect an older biological age.
Aim for seven to nine hours of sleep per night. If you struggle to meet these recommendations, Patel suggests reallocating some of your typical screen time to rest. If you spend 90 minutes a day on social media, for example, cut back to 30 minutes. That way, you have an extra hour for sleep. “I’m realistic; I’m not telling you to stop using screens,” Patel says. “But could you cut back?”
6. Chronic Stress
Some stress is unavoidable. But when stress levels are consistently high, so are levels of the stress hormone cortisol, which can prematurely age your skin, Karim says. Preliminary research suggests cortisol increases fine lines and wrinkles, changes skin DNA at the cellular level, and impedes skin healing.
Cortisol is also linked with DNA changes and cell death that signal premature aging within many of your body’s systems. “Chronic stress can lead to an acceleration of biological aging and increased risk for a variety of age-related diseases,” Kaeberlein says.
Plus, stress can undermine other healthy habits by disrupting sleep, interfering with exercise, and driving poor food choices, Brar says. This creates a cascade of effects that accelerate aging.
You won’t be able to banish all stress, but you can improve the way you cope with it. “We’re always going to have stress in our lives, and so we have to develop ways to address it proactively,” Kaerberlein says.
The most effective stress management techniques to prevent premature aging and other health concerns include journaling, meditation, spending time in nature, being around loved ones, and talking with a mental health care provider when needed.
7. Too Much Added Sugar
Foods high in added sugars cause blood sugar spikes that degrade the collagen in your skin. This collagen loss reduces the plumpness and firmness characteristic of youthful skin, Karim says.
Over time, the extra calories from too much sugar can contribute to weight gain by your mid-thirties, Kaeberlein says. Higher body weight increases the risk of age-related conditions like diabetes and heart disease, while excess body fat drives inflammation that damages tissue and skin.
To cut back on added sugars, satisfy your sweet tooth with naturally sweet foods like fruit, which contain skin-friendly antioxidants that may counteract skin aging. You can also swap sugar-sweetened sodas, sports drinks, and juice for unsweetened versions or sparkling water with lemon.
The Takeaway
- Research suggests that the cumulative effects of unhealthy habits can begin showing up in your mid-thirties, causing your biological age to rise faster than your chronological age.
- Some of the habits that prematurely age you include smoking, drinking alcohol, being sedentary and chronically stressed, and not getting enough sleep.
- Small but sustainable steps toward healthier habits can lower your biological age.
EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
- Kekäläinen T et al. Cumulative Associations Between Health Behaviours, Mental Well-Being, and Health Over 30 Years. Annals of Medicine. April 2025.
- Understanding the Difference Between Biological Age and Chronological Age. Mayo Clinic. July 2024.
- Kotlyarov S. The Role of Smoking in the Mechanisms of Development of Chronic Obstructive Pulmonary Disease and Atherosclerosis. International Journal of Molecular Sciences. May 13, 2023.
- Hergesell K et al. The Effect of Long-Term Cigarette Smoking on Selected Skin Barrier Proteins and Lipids. Nature. July 2023.
- Yazdanparast T et al. Cigarettes Smoking and Skin: A Comparison Study of the Biophysical Properties of Skin in Smokers and Non-Smokers. Tanaffos. February 2019.
- Benefits of Quitting Smoking. Centers for Disease Control and Prevention. May 2024.
- Alcohol's Effects on the Body. National Institute on Alcohol Abuse and Alcoholism. June 2025.
- Lu M et al. Genome-Wide Associations Between Alcohol Consumption and Blood DNA Methylation: Evidence From Twin Study. Epigenomics. May 2021.
- About Moderate Alcohol Use. Centers for Disease Control and Prevention. January 2025.
- Nunan E et al. Obesity as a Premature Aging Phenotype — Implications for Sarcopenic Obesity. GeroScience. April 26, 2022.
- Physical Activity Guidelines for Americans, 2nd edition. U.S. Department of Health and Human Services. 2018.
- Protecting Skin From Sun Can Help Appearance of Aging. UCLA Health. February 2024.
- Photoaging: What You Need to Know About the Other Kind of Aging. Skin Cancer Foundation. June 2021.
- Signs of Premature Aging. Cleveland Clinic. May 2022.
- Sun-Protective Clothing. Skin Cancer Foundation.
- How to Choose the Best Sunglasses to Avoid Sun Damage. American Academy of Ophthalmology. May 29, 2024.
- About Sleep. Centers for Disease Control and Prevention. May 2024.
- Watson KB et al. Trends in Multiple Chronic Conditions Among US Adults, By Life Stage, Behavioral Risk Factor Surveillance System, 2013–2023. Preventing Chronic Disease. April 17, 2025.
- Carroll JE et al. Sleep and Biological Aging: A Short Review. Current Opinion in Endocrine and Metabolic Research. June 2022.
- Pujos M et al. Impact of Chronic Moderate Psychological Stress on Skin Aging: Exploratory Clinical Study and Cellular Functioning. Journal of Cosmetic Dermatology. January 2025.
- Yegorov YE et al. The Link between Chronic Stress and Accelerated Aging. Biomedicines. July 2020.
- Managing Stress. Centers for Disease Control and Prevention. June 2025.
- Skin-Friendly Diet? Learn What to Eat and What to Avoid. Kaiser Permanente Medicine. April 2025.
- Tucker LA et al. Weight Change Over Ten Years Predicts Biological Aging in a Random Sample of 3070 U.S. Adults. Nutrients. June 2023.
- Tranchida N et al. Potential Role of Dietary Antioxidants During Skin Aging. Food Science & Nutrition. May 2025.
- Cut Back on Added Sugars. U.S. Department of Agriculture.
Meet Our Experts
Simran Malhotra, MD
Medical Reviewer
Member of American College of Lifestyle Medicine
Simran Malhotra, MD, DipABLM, CHWC, is a triple board-certified physician in internal medicine, hospice and palliative care, and lifestyle medicine, as well as a certified health a...
Sarah Klein
Author
Sarah Klein is a Boston-based health journalist with more than 15 years experience in lifestyle media. She has held staff positions at Livestrong, Health, Prevention, and Huffingto...