These go way beyond teenage tanning coming back to haunt your skin.
Your Lunchtime Soda
What it ages: Your bones
The science: Older women who drank a cola every day had significantly lower bone-mineral density than those who consumed less than one cola per month, according to a study in the American Journal of Clinical Nutrition. It's not exactly clear why cola had this effect, but the study researchers believe that it could be the combination of caffeine and phosphoric acid (which most other carbonated drinks don't have) that causes the problem.
What you can do: Cut back. Keep in mind that diet cola had similar effects and, to a lesser extent, so did decaf versions. If you need bubbles, try seltzer instead.
Your Daily Commute
What it ages: Your skin
The science: The air you're exposed to on the highway is no friend to your complexion. Traffic-related pollution can lead to age spots, according to a review in the Journal of Investigative Dermatology, while another review in Frontiers in Environmental Science found that pollution contributes to overall skin aging, plus other problems like acne, eczema and psoriasis.
What you can do: Until someone comes up with a way to make a long commute shorter (get on that, scientists), these tips should help. First, if you drive an older car, roll your windows down instead of up when you're sitting in traffic. (With an older air-filter system, you'll just breath in your car's own exhaust if you keep them up). Second, apply a topical antioxidant product to your face, neck and chest in the morning to help protect your skin from environmental pollution.
A Hypercritical Boss
What it ages: Your brain
The science: Anxiety and stress can shrink your hippocampus, and in people already experiencing the cognitive decline that can lead to Alzheimer's, they could potentially speed up the progression of the disease.
Your hippocampus controls memory formation and also plays a role in regulating your emotions. It naturally gets smaller as we age, but a review in Current Opinion in Psychiatryfound that stress can cause structural damage and accelerate the shrinking process. "Cortisol is released when you're stressed and cortisol is toxic to the hippocampus," explains lead study author Linda Mah, MD, an assistant professor of psychiatry at the University of Toronto and clinical scientist at the Baycrest Centre for Geriatric Care. Before you get stressed and anxious about how stress and anxiety are affecting your brain, know this: The researchers concluded that "pathological anxiety and chronic stress" are the real dangers, meaning the kind that's unrelenting and never seems to go away. If you think that's what you're experiencing, talk to your doctor about ways to manage it.
Dr. Mah led another study in 2014 focusing on people with mild cognitive impairment, or MCI. (MCI is considered a precursor to Alzheimer's. Not everyone with MCI develops Alzheimer's, but almost all cases of Alzheimer's start as MCI.) Subjects who experienced anxiety at any time were more likely to progress to Alzheimer's during the three-year study. The more severe the anxiety, the higher the risk.
What you can do: You've heard this before, but managing your stress levels is incredibly important. Exercise may be particularly helpful in dealing with work worries, according to a new study in the journal Medicine and Science in Sports and Exercise, which reported that being physically fit helped protect against the health effects of work-related stress.
What they age: Your cells
The science: A startling discovery comes via a study in Biological Psychiatry, which reported that women with five key symptoms of insomnia were almost two years older biologically than women of the same age without sleep issues. (The insomnia symptoms were difficulty falling asleep, restlessness, waking up during the night, trouble dozing off again and waking up too early.) This study didn't show a cause-and-effect relationship, but study author Steve Horvath, PhD, a professor of human genetics and biostatistics at UCLA's David Geffen School of Medicine, notes that it's still good reason not to let sleep issues linger.
What you can do: Treat the insomnia. If you're having trouble sleeping, or notice any of the five symptoms above, ask your doctor for help.
An Expanding Waistline
What it ages: Your brain
The science: Our brains naturally lose white matter with age, but researchers from the University of Cambridge found that the brains of middle-age overweight and obese people had the same amount of white matter as healthy people 10 years older than them. Being physically unfit in middle age was also linked to smaller brain size 20 years later, according to research in Neurology.
What you can do: Get regular exercise (the U.S. Department of Health and Human Services recommends at least 150 minutes of moderate aerobic exercise, or 75 minutes of vigorous exercise, per week) and manage your weight to help keep your brain at a healthy size for your age.
#1. Use the gold-standard treatment for thinning hair
Age-related thinning usually starts at the part, where you'll notice a <a href="http://www.oprah.com/health_wellness/Reasons-Your-Hair-Is-Thinning/2" target="_blank">gradual widening</a>. (Experts don't know why it begins there). To keep your hair looking full, try minoxidil, which is FDA-approved to stimulate growth. Stronger 5-percent solutions are available for women as of 2014, in addition to 2-percent formulas. (If you're noticing other <a href="http://www.oprah.com/health_wellness/Reasons-Your-Hair-Is-Thinning" target="_blank">types of thinning</a>, we've got solutions for those too.)