Nearly 75% of Americans use dietary supplements to improve health or address nutritional gaps. However, some popular products may unintentionally interfere with sleep. Here are three supplements to be mindful of, and why this matters: poor sleep isn’t just about feeling tired — it has long-term consequences for physical and mental health, including weakened immunity, impaired cognitive function, and increased risk of chronic diseases.
Caffeine-Containing Supplements: Hidden Stimulants
Many supplements marketed for energy, weight loss, or pre-workout performance contain caffeine. Pieter Cohen, MD, of Harvard Medical School, explains that these products can disrupt sleep if taken too close to bedtime. The issue is that caffeine content isn’t always accurately labeled, making it difficult for consumers to know how much they’re actually ingesting. Some products don’t list caffeine at all, hiding stimulants in proprietary blends.
This lack of transparency is a growing concern because consumers rely on labels to make informed choices. Without clear dosage information, even a small amount of hidden caffeine can disrupt sleep patterns.
Vitamin B12: A Complex Relationship with Sleep
Vitamin B12 is crucial for nerve function and energy production. While it can help regulate melatonin in people with deficiencies, some research suggests it may reduce sleep duration. A small study found that methylcobalamin, a form of B12, was associated with less sleep, though not necessarily poorer sleep quality.
The connection remains unclear: research is mixed, and additional studies are needed to fully understand how B12 impacts sleep and circadian rhythms. Experts emphasize the need for more comprehensive research before drawing definitive conclusions.
Multivitamins: A Potential, Though Unclear, Link to Sleep Issues
While evidence is weak, multivitamins may disrupt sleep for two main reasons. First, many contain vitamin B12, which, as discussed, has a complex relationship with sleep. Second, one study found that multivitamin users reported higher rates of insomnia and nighttime awakenings compared to non-users.
However, experts caution against overinterpreting these findings. One study alone is not enough to establish causation, and the research had limitations, including a small sample size and self-reported data. More robust studies are needed to confirm whether multivitamins truly affect sleep.
In conclusion, while supplements can be beneficial, consumers should be aware of potential side effects. Carefully review labels, consider timing, and discuss concerns with a healthcare provider to optimize health without sacrificing sleep. If you’re experiencing sleep disturbances, it’s essential to evaluate all contributing factors, including supplement use, to identify and address the root cause.
