Beyond Caffeine: Unveiling Other Compounds That May Disturb Your Sleep

Question: If I find that even decaf coffee seems to affect my sleep quality, what’s a common ingredient in some coffee roasts or processing that might be responsible for this sensitivity?

While caffeine is the most recognized stimulant in coffee, responsible for that invigorating morning boost and, for some, restless nights, its removal in decaffeinated varieties doesn’t always guarantee uninterrupted sleep. If you find that even decaf coffee seems to affect your sleep quality, it’s worth exploring other compounds and processing influences that might be at play.

The Role of Coffee Species and Processing

The type of coffee bean, specifically Coffea arabica versus Coffea canephora (robusta), can influence the overall chemical profile of the coffee. While robusta beans are often associated with higher caffeine content, the interplay of various compounds can differ. For instance, research indicates that Coffea arabica may have a higher lipid content, which could affect foam stability in espresso [1]. Furthermore, processing methods, such as fermentation, can significantly alter the chemical composition and perceived quality of coffee [3]. Aerobic and anaerobic fermentation treatments, for example, have been shown to positively influence pH, acidity, and the concentration of volatile compounds, while CO₂ treatment can have an inhibitory effect [3]. Different mucilage retention treatments during honey processing of Arabica coffee can also impact its flavor profile [6]. These variations in processing parameters can lead to a diverse array of compounds, some of which might contribute to sensitivities.

Volatile Compounds and Flavor Modulators

Beyond caffeine, coffee is a complex beverage containing hundreds of volatile compounds that contribute to its aroma and flavor. These include a wide range of esters, alcohols, and acids. For example, compounds like phenylethyl alcohol, octanoic acid ethyl ester, hexanoic acid ethyl ester, and β-damascenone have been identified as key flavor contributors, imparting notes of brandy, honey, spice, fruit, smoke, floral, and sweetness [5]. While these compounds are generally prized for their sensory contributions, their impact on sleep quality can vary significantly between individuals. The presence and concentration of these volatile compounds can be influenced by both the bean species and the processing methods employed [3, 6]. Even in decaffeinated blends, these compounds are retained and contribute to the coffee’s overall sensory experience [7].

Other Potential Influences

While not directly related to typical coffee processing, it’s worth noting that compounds like amino acids, tribigonelline, and chlorogenic acid are also present in coffee, with their concentrations varying between Arabica and Robusta varieties [2]. Chlorogenic acids, for instance, are known for their antioxidant properties [8], but their broader physiological effects, including any potential impact on sleep, are less understood and could differ from caffeine. The water activity and pH of coffee co-products, for example, can vary between species and processing methods, suggesting a complex matrix of potentially bioactive compounds [4].

In conclusion, if you experience sleep disturbances even after consuming decaffeinated coffee, the cause may not be limited to caffeine. The inherent differences in coffee species, coupled with the intricate transformations that occur during various processing stages like fermentation and mucilage retention, can introduce a spectrum of compounds that might individually or collectively influence your sleep quality.

References

[1] — Ernesto Illy, Luciano Navarini — Neglected Food Bubbles: The Espresso Coffee Foam. — 2011-Sep — https://pubmed.ncbi.nlm.nih.gov/21892345/ [2] — Magdalena Zdanowicz, Marta Rokosa, Magdalena Pieczykolan, Adrian Krzysztof Antosik, Katarzyna Skórczewska — Biocomposites Based on Wheat Flour with Urea-Based Eutectic Plasticizer and Spent Coffee Grounds: Preparation, Physicochemical Characterization, and Study of Their Influence on Plant Growth. — 2024-Mar-06 — https://pubmed.ncbi.nlm.nih.gov/38473683/ [3] — Gustavo Galarza, Jorge G Figueroa — Volatile Compound Characterization of Coffee ( — 2022-Mar-21 — https://pubmed.ncbi.nlm.nih.gov/35335365/ [4] — Katarína Poláková, Alica Bobková, Alžbeta Demianová, Marek Bobko, Judita Lidiková, Lukáš Jurčaga, Ľubomír Belej, Andrea Mesárošová, Melina Korčok, Tomáš Tóth — Quality Attributes and Sensory Acceptance of Different Botanical Coffee Co-Products. — 2023-Jul-11 — https://pubmed.ncbi.nlm.nih.gov/37509767/ [5] — Rongsuo Hu, Fei Xu, Liyan Zhao, Wenjiang Dong, Xingyuan Xiao, Xiao Chen — Comparative Evaluation of Flavor and Sensory Quality of Coffee Pulp Wines. — 2024-Jun-27 — https://pubmed.ncbi.nlm.nih.gov/38999011/ [6] — Faguang Hu, Haohao Yu, Xingfei Fu, Zhongxian Li, Wenjiang Dong, Guiping Li, Yanan Li, Yaqi Li, Bingqing Qu, Xiaofei Bi — Characterization of volatile compounds and microbial diversity of Arabica coffee in honey processing method based on different mucilage retention treatments. — 2025-Jan — https://pubmed.ncbi.nlm.nih.gov/39974542/ [7] — Danijela Šeremet, Patricia Fabečić, Aleksandra Vojvodić Cebin, Ana Mandura Jarić, Robert Pudić, Draženka Komes — Antioxidant and Sensory Assessment of Innovative Coffee Blends of Reduced Caffeine Content. — 2022-Jan-10 — https://pubmed.ncbi.nlm.nih.gov/35056759/ [8] — Zofia Kobylińska, Marek Biesiadecki, Ewelina Kuna, Sabina Galiniak, Mateusz Mołoń — Coffee as a Source of Antioxidants and an Elixir of Youth. — 2025-Feb-27 — https://pubmed.ncbi.nlm.nih.gov/40227264/