7 Habits That Impact 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.
“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.
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.
2. Too Much Alcohol
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.
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.

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.
5. Poor Sleep
6. Chronic Stress
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.
7. Too Much Added Sugar
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.
- 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.

Simran Malhotra, MD
Medical Reviewer
Dr. Malhotra completed her internal medicine residency at Medstar Franklin Square Medical Center, where she also served as chief resident in 2015. She completed her fellowship in hospice and palliative medicine at Johns Hopkins Hospital in 2016. She was named Top Doc in Palliative Medicine in 2019 and 2020 by Baltimore Magazine.
On a personal note, she is a BRCA1 previvor with a strong family history of breast and female reproductive cancers, and underwent a risk-reducing bilateral mastectomy and total hysterectomy in 2020 at 32 years old. After learning about her own genetic risk of cancer, and grounded in her professional experiences in palliative care, she founded Wellness By LifestyleMD, a platform where she works with and educates women at high risk for cancer with or without genetic mutations on the powerful impact that positive lifestyle changes can have on their quality of life and even longevity.
In addition to being a diplomate of the American College of Lifestyle Medicine, she completed the T. Colin Campbell plant-based nutrition certification in 2019, the CHEF culinary coaching certification in 2020, and the WellCoaches health and wellness coaching certification in 2022. She is a member of the ACLM women’s health member interest group and serves as the co-chair of the breast cancer subcommittee.
Malhotra has been featured on several blogs and podcasts, where she has shared her unique perspectives and experiences from palliative care as well as from being a genetic mutation carrier who is passionate about using lifestyle as medicine.

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 Huffington Post. She is a graduate of the Arthur L. Carter Journalism Institute at New York University, and a National Academy of Sports Medicine–certified personal trainer. She moderated a panel on accessibility in fitness at SXSW in 2022, completed the National Press Foundation’s 2020 Vaccine Boot Camp, and attended Mayo Clinic’s Journalist Residency in 2019.