Does Liquid Collagen Keep You Up at Night?

December 15, 2025 •

4 min read

Research suggests that collagen is rich in glycine, an amino acid known for its calming properties and positive effects on sleep quality. This is in direct contrast to the popular concern that a supplement might cause restlessness. In fact, many individuals intentionally take collagen at night as part of their routine to improve rest.

Quick Summary

This article examines the truth behind whether liquid collagen can disrupt sleep, revealing how its high glycine content can actually promote relaxation and deeper rest. It covers the mechanisms by which collagen supports sleep and explains what to look for in a supplement to avoid any unwanted stimulating ingredients.

Key Points

Glycine promotes relaxation: Collagen is rich in the amino acid glycine, which calms the nervous system and can help promote restful sleep.
Lowering body temperature: Glycine helps lower core body temperature, a key physiological signal for the body to initiate sleep.
Check for stimulating additives: Some liquid collagen products contain added ingredients like caffeine or sugar, which can interfere with sleep; always read the label.
Timing is important: For best results, take liquid collagen about 30-60 minutes before bed to align with your body's natural wind-down process.
Supports hormonal balance: Glycine supports the production of serotonin and melatonin, hormones critical for regulating sleep patterns.
Enhances natural repair: Nighttime is when the body focuses on repair; providing it with collagen can support this natural regeneration of skin, joints, and other tissues.
Addresses underlying sleep issues: While beneficial, collagen is not a magic fix for severe sleep disorders. It's a supportive tool for improving sleep quality, particularly for those with mild sleep complaints.

The Role of Glycine: Collagen's Calming Amino Acid

Collagen is the most abundant protein in the human body, but when it comes to sleep, its high concentration of the amino acid glycine is the real star. Glycine is an inhibitory neurotransmitter that plays a crucial role in regulating the central nervous system, helping to calm the brain and body. It promotes a state of relaxation without causing heavy sedation, making it a valuable tool for those with mild sleep disturbances. Glycine also supports the body in two key ways that directly impact the sleep cycle:

Lowering core body temperature: A slight drop in core body temperature is a natural signal for the body to transition into sleep. Glycine has been shown to assist with this process by increasing blood flow to the extremities, which helps cool the body down.
Enhancing melatonin and serotonin production: Glycine helps boost the production of serotonin, a neurotransmitter that is a precursor to melatonin—the primary hormone that regulates the sleep-wake cycle. By supporting this pathway, collagen can help regulate and stabilize your circadian rhythms.

Potential Culprits: When Liquid Collagen Might Cause Restlessness

While the core components of collagen are typically beneficial for sleep, some individuals report restlessness. The source of this issue is almost never the collagen itself but rather other ingredients present in the liquid formula. To determine if your supplement is problematic, check for the following:

Stimulating additives: Some collagen products, especially those marketed for energy or athletic performance, may contain ingredients like green tea extract, guarana, or other stimulants. These are clear offenders for disrupting sleep and should be avoided in evening doses.
High-sugar content: Liquid supplements often come with added sugars or artificial sweeteners to improve taste. High sugar intake before bed can lead to blood sugar spikes and crashes, which can disrupt sleep patterns.
Individual sensitivities: Everyone's body is different, and some people may have sensitivities to the ingredients or fillers in certain supplements. Although rare, a mild digestive reaction or individual intolerance could affect sleep quality.

How to Optimize Your Nightly Collagen Routine

For those who wish to use liquid collagen to support better sleep, timing is crucial. Studies suggest taking collagen peptides approximately 30 to 60 minutes before bedtime allows the glycine to reach its peak concentration in the bloodstream at the optimal time for promoting sleep. Combining your supplement with a relaxing bedtime ritual can further amplify its benefits.

Warm beverage: Mixing your collagen powder into a warm, caffeine-free beverage like herbal tea or warm milk can create a soothing ritual that signals to your body it's time to unwind.
Consistency is key: For maximum benefit, it's important to be consistent with your nightly routine. The sleep-regulating effects of glycine may become more pronounced with regular, long-term use.

Comparison Table: Collagen for Sleep vs. Common Sleep Aids


Feature	Liquid Collagen (with Glycine)	Melatonin Supplements	Magnesium Supplements
Mechanism of Action	Promotes relaxation by calming the nervous system and lowering body temperature.	Directly signals the body to sleep by regulating the sleep-wake cycle.	Relaxes muscles and nerves, and supports inhibitory neurotransmitters like GABA.
Effectiveness for Sleep	Helps reduce sleep fragmentation and nocturnal awakenings, and improves next-day cognitive function, particularly in those with sleep complaints.	May help some people fall asleep faster, but can be less effective for maintaining sleep throughout the night.	Effective for promoting relaxation and can help improve overall sleep quality.
Daytime Effects	May reduce next-day fatigue and improve alertness and cognitive function.	Can sometimes cause grogginess or feelings of disorientation the next morning, especially with higher doses.	Generally does not cause daytime drowsiness, but high doses can cause gastrointestinal issues.
Additional Benefits	Supports skin elasticity, joint health, and gut integrity.	Often paired with other sleep aids; limited additional benefits for other systems.	Supports muscle function, bone health, and stress management.
Potential Side Effects	Mild digestive upset in some cases; can be influenced by other additives in the formula.	Headaches, dizziness, nausea.	Nausea, stomach cramps, diarrhea with high doses.

Conclusion: The Final Verdict on Collagen and Sleep

The idea that liquid collagen keeps you up at night is largely a misconception driven by potentially problematic additives in certain products rather than the collagen itself. In fact, due to its high concentration of glycine, collagen is more likely to promote restful sleep by calming the nervous system, lowering core body temperature, and supporting the body's natural sleep-regulating hormones. For those seeking better sleep, a clean, high-quality liquid collagen taken about an hour before bed can be a natural and effective addition to a healthy nightly routine. By understanding the role of glycine and avoiding stimulating ingredients, you can leverage liquid collagen to support a more restorative night's rest and wake up feeling refreshed. If you experience any persistent sleep disruption, it is always best to consult a healthcare provider to rule out underlying issues.

The link between sleep and skin repair

During deep sleep, the body's cellular repair and regeneration processes are most active. This is when collagen synthesis naturally peaks, helping to repair and renew skin cells and other tissues. Providing your body with the necessary building blocks through collagen supplementation can support this nocturnal repair cycle, leading to healthier skin and joints over time. Chronic poor sleep, on the other hand, can raise cortisol levels, which breaks down collagen and accelerates the aging process. This creates a vicious cycle where poor sleep damages collagen, and a lack of collagen can then impact restorative sleep. By promoting better sleep, collagen supplementation offers a double benefit: it provides the amino acids needed for repair and supports the quality rest required for the process to be most effective.

Frequently Asked Questions

No, liquid collagen itself is not a stimulant and is more likely to promote relaxation than cause restlessness. The restlessness is more likely a result of other stimulating ingredients, like caffeine or high amounts of sugar, added to some supplements.

The glycine in collagen has a calming effect on the central nervous system, and studies suggest it can help you fall asleep faster and improve sleep quality. It does not act as a sedative but rather helps facilitate your body's natural sleep processes.

Taking liquid collagen approximately 30 to 60 minutes before bedtime is recommended for sleep benefits. This allows the glycine to be absorbed and work in harmony with your body's natural wind-down phase.

For most people, taking collagen before bed has no negative side effects. Some individuals may experience mild digestive issues like bloating or a feeling of fullness. Always check for potential allergens like fish or eggs.

Collagen is rich in glycine, an amino acid that supports the production of serotonin. Serotonin is a precursor to melatonin, the hormone that regulates your sleep-wake cycle, so collagen can indirectly help balance melatonin levels.

Yes, research indicates that collagen peptide supplementation can lead to better overall sleep quality by reducing nighttime awakenings and helping the body enter deeper, more restorative sleep phases.

The format (liquid vs. powder) typically does not matter for the effects of collagen on sleep. The crucial factor is the presence of high-quality hydrolyzed collagen peptides and the absence of stimulating additives. Liquid forms may offer slightly faster absorption but are not necessarily superior.

Studies showing improved sleep quality suggest that consuming a certain amount of collagen peptides can be beneficial for sleep. The amount of glycine in these peptides contributes to the effect.