Sleep. We all need it. And most of us want more of it. For the millions suffering from sleep issues, there are plenty of dietary supplement options that can help you fall asleep and stay asleep. But what about the other side of the pillow? What supplements should you dodge before bedtime? In general, you should try to avoid products that have a stimulating impact on the body or provide a sensory effect. These energizing or stimulating ingredients and products may have a direct impact on your sleep. 


The intent of a pre-workout supplement is to give you a boost of energy to help push through a tough exercise session. Which is the exact opposite of what you want right before bedtime. Pre-workouts typically contain energizing ingredients such as caffeine. If you like to work out at night, give non-stimulant versions of thermogenics or pre-workouts a try. 


Typically found in coffee and fizzy drinks, caffeine is the most commonly used stimulant in the world. And for good reason. Caffeine stimulates the central nervous system, muscles and other organs, which can enhance mental alertness, reduce fatigue and improve exercise performance. This energizing compound reaches peak concentrations around 45 minutes after consumption and the effects can last hours. 

The half-life of caffeine is about 4 to 5 hours, which means that half the caffeine you consume will be eliminated by the body in 4 to 5 hours, but the other half will still have lingering effects.23 Scientific evidence shows that caffeine can prolong the time it takes to fall asleep, reduce total sleep time and worsen perceived sleep quality.4 While there are individual differences in caffeine metabolism and sensitivity, it is generally recommended to avoid caffeine at least 6 hours before bedtime.23

When it comes to supplements, you’ll have to check the facts panel to see if they contain caffeine. The usual suspects are products such as pre-workouts, thermogenics (or fat burners), and energy pills, shots and drinks. However caffeine can be found in other surprising products, such as multivitamins. 

Keep an eye out for these ingredients, which are common sources of caffeine:3

  • Cocoa (cacao, Theobroma cacao)
  • Coffee or coffea
  • Green coffee bean
  • Guarana
  • Kola nut
  • Methylxanthine
  • Tea (Camellia sinesis)
  • Trimethylxanthine
  • Xanthine
  • Yerba mate


Beta-alanine, a type of amino acid, is commonly used by fitness enthusiasts to help with athletic performance. Beta-alanine is responsible for the “tingly” feeling you may experience after taking a pre-workout (some love this feeling, while others don’t). Also known as paresthesia, this tingling, prickling or burning sensation in the face, neck, hands and other parts of the body lasts about 60–90 minutes (about the length of a gym session) and could impact your ability to fall asleep. 

When Should I Take Supplements?

That’s a loaded question. The answer depends on the products you are taking and your goals. 

In general, the science says you may be more likely to stick to a habit if you incorporate supplements into your morning routine. One study evaluated adherence of taking a medication dosed once in the morning and once at night. Results showed that the number of missed doses in the evening were significantly greater than missed doses in the morning.4 While this study evaluated medications and not supplements, it still suggests that you may be more compliant with a morning regimen than one at bedtime. 

Listen To Your Body

Everyone’s body is unique and different. For that reason, supplements can impact each of us differently. Even though uncommon, some can experience unpleasant reactions such as an upset stomach after taking a product. Those types of reactions can impact the quality of your sleep. Bottom line: Listen to your body. Your ZZZs will thank you.