When you’ve lived with type 2 diabetes for a while, you become a pro at managing your glucose levels. You know that it’s best to limit carbs, exercise regularly, check other medications for possible interactions, and avoid drinking alcohol on an empty stomach.

By now, you may be well attuned to how your day-to-day activities impact your blood glucose. So if you see a big shift in your A1c levels that you can’t explain, you might be surprised and frustrated.

Sometimes, things you may not even think about can affect your blood glucose, which can in turn lead to serious complications, such as heart attacks, kidney disease, blindness, or amputation. Learning to recognize behaviors and circumstances that you don’t normally associate with blood glucose fluctuations may help you prevent more serious problems now and in the future.

1. Misdiagnosis

If your once-controlled A1c has spun out of control despite your best efforts, it’s possible you don’t have type 2 diabetes at all. In fact, according to the American Diabetes Association (ADA), about 10 percent of people diagnosed with type 2 diabetes actually have latent autoimmune diabetes (LADA). The incidence is significantly higher for those under 35 years of age: About 25 percent of people in that age group have LADA.

In a 2015 report, doctors noted that LADA is manageable with the same regimen used by type 1 patients. The condition progresses slowly, but it ultimately does require insulin treatment. If you’ve been successfully treated for type 2 diabetes for several years or more, a sudden change in your ability to manage your A1c levels might be a sign of LADA. It’s worth taking the time to talk to your doctor about the issue.

2. Changes to your supplement regimen

These days, it seems like every vitamin, mineral, and supplement on the market is a “magic bullet” for something. But some nutritional supplements can affect your A1c test and lead to inaccurate test results.

For example, according to a paper published in the Journal of General Internal Medicine, high levels of vitamin E can falsely elevate A1c levels. On the other hand, vitamins B-12 and B-9, also known as folic acid or folate, can falsely lower them. Vitamin C can do either, depending on whether your A1c test measures by electrophoresis, which can show a false increase, or by chromatography, which can return a false decrease. Always consult with your doctor or dietitian before making any substantial changes to the supplements you take.

It’s important to note that some prescription medications, such as interferon-alpha (Intron A) and ribavirin (Virazole), can impact A1c testing too. If you’ve been prescribed a medication that might affect your blood glucose levels or the accuracy of your A1c test, your doctor or pharmacist should discuss this with you.

3. Major life events

Stress, especially chronic stress, can raise blood glucose levels and increase insulin resistance, according to the ADA. You may be able to recognize when you’re under “bad” stress. You may also know that it elevates levels of the hormones that in turn raise blood glucose. What you might not realize is that even the most positive life events can also be a source of stress.

Your body doesn’t know how to differentiate the bad stress from the good. You may not think to associate happy, exciting times in your life with bad A1c results, but there could be a connection. Even the best life changes — a new love, a big promotion, or buying your dream home — can lead to an increase in the hormones associated with stress.

If you’re experiencing major life changes — whether good or bad — it’s important to practice good self-care. The ADA suggests making time for stress-relieving practices, such as breathing exercises and physical activity. Keep this in mind, and stay on top of your blood sugar proactively when major changes are on the horizon.

The takeaway

Under most circumstances, type 2 diabetes can be well-controlled with good lifestyle choices and attention to our emotional well-being as well as medications. When your best efforts don’t get the job done, look deeper. There are often little-considered factors that can throw us out of balance. Once recognized and addressed, most of us can regain our equilibrium and be on the road to steady glucose levels.