Q: I’m 43 and have started jogging and cycling a lot, but I am worried that I am setting myself up for arthritis in my knees. How can I protect myself? — Sarabeth L., Chicago

A: Jogging and cycling can, over time and in certain people, trigger knee problems — tendon thickening, meniscus tears, ACL damage and cartilage erosion. Those issues often result from overuse, overtraining and sometimes poor equipment or falls and accidents. But it turns out that the one thing jogging and cycling don’t typically cause is osteoarthritis.

One 10-year study in the journal The Knee explored the causes of knee injuries that lead to surgery: Around 20% were ACL-related, 11% medial meniscus, 4% lateral meniscus and 8% from a medial collateral ligament lesion. Soccer and skiing led to the most injuries. Jogging was associated only with medial meniscus damage.

Now a study in Arthritis & Rheumatology that analyzed data from six studies with 5,065 participants found that whole-body physical activity in sports, walking or cycling wasn’t associated with developing knee osteoarthritis — at all.

Forever, we have thought of arthritis as a wear-and-tear joint affliction. But it turns out that it is really a much more complex disorder related to genetics, inflammation, body weight, muscle tone and individual biology. And because of that, studies such as one in Clinical Rheumotology have found that among individuals over 50 years old with knee osteoarthritis, running is associated with improved knee pain and not with worsening knee pain or structural damage. In fact, runners have a lower incidence of osteoarthritis of the knee and hip when compared with nonrunners. Exercise reduces chronic inflammation!

That doesn’t mean you won’t experience aches and pains from time to time. Just ice, rest and repair, so you don’t turn discomfort into injury. And avoid overuse injuries by alternating cycling and jogging, and jogging on a padded track or treadmill.

Q: I am thinking a lot about climate change and what I can do every day that might make a positive contribution to reducing the problems it is causing. Any suggestions? — David J., Worcester, Mass.

A: Save yourself, help the planet — that’s a motto we like. That’s because by eliminating red meats, avoiding using plastics as much as possible and opting to walk or cycle instead of drive, you are making huge improvements in your health — and contributing to the easing of climate change. And now a study out of Australia — which applies big time to folks in the U.S. — is suggesting another powerful boost to your health that also helps the planet: Giving up sugar-added foods and drinks and fried and processed foods.

According to the study in Current Nutrition Reports, it is processed foods, sugar-sweetened drinks, alcohol, sweets and processed meats that account for 27% to 33% of food-related greenhouse gas emissions in Australia. In addition, food-related carbon emissions account for around 14% of the total carbon pollution there and every single resident produces 19.7 kilograms of carbon dioxide each day through their diet!

We do similar damage here. A study in the American Journal of Clinical Nutrition found that 57% of Americans’ calories come from health- and climate-damaging ultraprocessed foods, while the intake of whole foods (fresh veggies, grains, fruits, etc.) plummeted to 27.4% of calories.

So, opt for a plant-based diet (a Mediterranean diet can slash your risk of recurrent heart disease by 50% to 70%) or go vegetarian, stick with water and unsweetened coffee and tea for beverages, and say no to highly processed foods. You’ll reduce your risk for everything from diabetes and depression to cancer. And according to the Centers for Disease Control and Prevention, you’ll also help to reduce the health risks that come directly from climate change — increased respiratory and cardiovascular disease, injuries and premature deaths related to extreme weather events, water-borne illnesses and other infectious diseases, and threats to mental health. If battling climate change and improving your health substantially doesn’t give you incentive to upgrade your diet, what will?

Mehmet Oz, M.D. is host of “The Dr. Oz Show,” and Mike Roizen, M.D. is Chief Wellness Officer Emeritus at Cleveland Clinic. Email your health and wellness questions to Dr. Oz and Dr. Roizen at youdocsdaily@sharecare.com.