Researchers followed thousands of older adults in Tehran for 16 years to understand how many people take dietary supplements and whether these supplements might cause problems when mixed with prescription medications. They discovered that supplement use among seniors has been increasing over time, and many people are taking supplements that could potentially interact with their regular medications in ways that might reduce effectiveness or cause side effects. This long-term study helps doctors and patients understand an important health concern that often goes unnoticed.

The Quick Take

  • What they studied: How many older adults take dietary supplements (like vitamins, herbs, and minerals) and whether these supplements might cause problems when taken together with prescription medications
  • Who participated: Older adults living in Tehran, Iran who were followed for 16 years as part of a larger health study tracking their diet, blood sugar, and heart health
  • Key finding: The number of older adults taking dietary supplements increased significantly over the 16-year period, and a notable portion of these people were taking supplements that could potentially interfere with their medications
  • What it means for you: If you’re an older adult taking both supplements and prescription medications, it’s important to talk with your doctor or pharmacist about potential interactions. They can help you understand which combinations are safe and which ones might need adjustment.

The Research Details

This was a long-term follow-up study, meaning researchers tracked the same group of people over 16 years and checked in with them at different time points to see how their supplement use changed. The researchers collected information about what supplements people were taking, what medications they were using, and their overall health status. They then analyzed this information to identify patterns in supplement use and looked for potential problems that could occur when supplements and medications are taken together. This type of study is valuable because it shows real-world patterns over a long period, rather than just looking at one moment in time.

Understanding how supplement use changes over time in older adults is important because seniors often take multiple medications, and adding supplements to the mix can create unexpected interactions. By studying this in a real population over many years, researchers can identify which combinations are most concerning and help doctors provide better guidance to their patients.

This study followed people for a long time (16 years), which makes the findings more reliable than shorter studies. The research was conducted as part of an established health study in Tehran, which means the data collection methods were standardized and well-documented. However, the study was conducted in Iran, so the results may not perfectly apply to older adults in other countries with different healthcare systems and supplement availability.

What the Results Show

The research found that the percentage of older adults taking dietary supplements increased substantially over the 16-year study period. This trend suggests that supplement use is becoming more common among seniors, which could be due to increased awareness, better availability, or changing health beliefs. The study identified several supplements that were commonly used by people also taking prescription medications. Many of these combinations had the potential to interact with each other, meaning the supplement could change how the medication works in the body. Some supplements might make medications less effective, while others might increase the risk of side effects.

The researchers also found that certain types of supplements were more likely to be used by people taking specific medications. For example, people with heart disease were more likely to take supplements alongside their heart medications. The study showed that many older adults were not aware that their supplements could interact with their medications, suggesting a gap in health communication between patients and healthcare providers.

This study confirms what other research has suggested: supplement use among older adults is increasing worldwide. Previous studies have shown similar patterns in developed countries, but this long-term follow-up provides stronger evidence that this is a sustained trend rather than a temporary change. The findings align with other research showing that many older adults don’t discuss their supplement use with their doctors.

The study was conducted in Tehran, Iran, so the results may not apply exactly to older adults in other parts of the world where different supplements are available and healthcare systems work differently. The study didn’t include detailed information about why people chose to take supplements or how much of each supplement they took. Additionally, the researchers could only identify potential interactions based on known drug-supplement relationships; they couldn’t determine how many people actually experienced problems from these interactions.

The Bottom Line

If you’re an older adult taking prescription medications, talk with your doctor or pharmacist before starting any dietary supplements, including vitamins, minerals, and herbal products. Make a complete list of everything you’re taking and share it with your healthcare provider. This conversation is especially important if you take multiple medications. (Confidence level: High - this is standard medical advice supported by extensive research)

This research is most relevant to older adults (especially those over 65) who take prescription medications. It’s also important for family members who help manage medications for aging relatives, and for healthcare providers who work with seniors. People who are generally healthy and take no medications have less reason to worry about supplement interactions, though it’s still good to inform your doctor about any supplements you use.

If a supplement is interfering with your medication, you might notice changes in how well your medication works within days to weeks, depending on the specific interaction. Some interactions develop slowly over time. The important thing is to have this conversation with your doctor before starting supplements, rather than waiting to see if problems develop.

Want to Apply This Research?

  • Create a complete inventory of all supplements and medications you take, including the dose and frequency of each. Update this list whenever you start or stop taking something, and review it with your doctor at least twice per year.
  • Before adding any new supplement to your routine, use the app to check it against your current medications and set a reminder to discuss it with your pharmacist or doctor within 24 hours. This creates a safety checkpoint before you start taking something new.
  • Set up monthly reminders to review your complete supplement and medication list. Track any new symptoms or changes in how you feel, and note any conversations you have with healthcare providers about your supplements. This creates a record you can reference and share with doctors.

This research describes patterns of supplement use and potential interactions in older adults. It does not provide personalized medical advice. Before starting, stopping, or changing any dietary supplement or medication, consult with your doctor or pharmacist. This is especially important if you take multiple medications or have chronic health conditions. The findings from this study conducted in Iran may not apply exactly to all populations. Always inform your healthcare provider about all supplements and medications you take.