From caffeine to trigonelline, coffee has surprising links to muscle biology

From NAD+ metabolism and glucose uptake to muscle mass and frailty, researchers mapped how espresso and its compounds work together with the organic processes that form skeletal muscle well being.

Evaluation: Coffee and coffee-derived bioactive compounds in skeletal muscle health: a scoping review of mechanistic pathways, preclinical evidence and human outcomes. Picture Credit score: Subbotina Anna / Shutterstock

In a latest examine revealed within the journal Food & Function, researchers reviewed proof on the results of espresso and its bioactive compounds on skeletal muscle (SM) well being.

Espresso is a extensively consumed beverage valued for its stimulating results, organoleptic properties, and potential well being advantages. It’s a main supply of bioactive compounds, equivalent to caffeine, hydroxycinnamic acids, trigonelline, and diterpenes, a few of which exhibit anti-inflammatory and antioxidant properties.

Recurring espresso consumption is linked to a decrease danger of sure cancers, heart problems, sort 2 diabetes, and neurodegenerative situations equivalent to Alzheimer’s and Parkinson’s illnesses. Nonetheless, the connection between espresso (and its bioactive compounds) and SM well being is poorly understood.

The examine and findings

Within the current examine, researchers reviewed proof on the results of espresso and its bioactive compounds on SM well being. First, a scientific literature search was performed throughout a number of databases to determine human, animal, and in vitro research evaluating the results of espresso, espresso extracts, or main bioactive compounds in espresso. Research revealed from 2014 to 2025 have been included.

Human research have been restricted to the final inhabitants, with research primarily centered on sports activities efficiency or ergogenic results excluded. Critiques, convention abstracts, meta-analyses, protocols, e-book chapters, and letters to editors have been excluded. Retrieved data underwent summary/title screening and full-text evaluation. Related knowledge, equivalent to examine traits, publicity, measures, and findings, have been extracted from research, and a story synthesis was carried out.

Of the 21,000+ data recognized by way of database searches, 54 research have been chosen for inclusion. These included 21 in vitro research, 19 animal research, 13 human research, and one examine with all three fashions. In vitro research predominantly used murine SM cell strains, with solely two research on human SM cells or myotubes. Ferulic acid was the most-studied phenolic compound in in vitro research.

Ferulic acid elevated the expression of myosin heavy chain isoforms I (MyHC I) and IIa (MyHC IIa) whereas decreasing MyHC IIb expression in murine myotubes, suggesting a shift in myogenic programming towards an oxidative fiber-type profile. One other examine reported that ferulic acid enhanced myoblast proliferation and differentiation in a dose- and time-dependent method, doubtlessly by way of elevated osteogenic gene expression.

A number of in vitro research indicated that caffeine might scale back myotube diameter and protein synthesis and promote cell dying, though many used concentrations significantly larger than these usually achieved in people after espresso consumption. The one in vitro examine on trigonelline confirmed that it elevated nicotinamide adenine dinucleotide (NAD+) ranges in differentiated human SM myotubes and first myotubes from aged mice. Likewise, the one in vitro examine on cafestol, a diterpene, discovered that it enhanced insulin-stimulated glucose uptake in differentiated human SM cells, which was akin to an anti-diabetic drug (rosiglitazone).

Animal research confirmed substantial variation in publicity time, route of administration, animal fashions, and dose. In a single examine, espresso supplementation elevated the load of a number of muscle mass, together with the gastrocnemius, extensor digitorum longus, quadriceps, and tibialis anterior, in male mice. Within the triceps, it additionally decreased the expression of remodeling development issue (TGF)-β and myostatin proteins, that are adverse regulators of muscle development.

One other examine confirmed that espresso administration elevated SM weight and grip energy in a murine mannequin of growing older. Moreover, espresso administration decreased fasting blood glucose however didn’t enhance muscle diameter or physique weight in diabetic rats in contrast with controls. Individually, espresso consumption elevated glucose oxidation and promoted muscle glycogen accumulation in rats fed a management eating regimen, however these results weren’t noticed in rats fed a high-fat eating regimen.

Human research have been restricted and predominantly observational, with solely two scientific trials. One trial reported decreased physique fats and elevated BIA-estimated SM mass after each day consumption of three cups of espresso for 12 weeks. The opposite trial reported that supplementation with a standardized decaffeinated inexperienced espresso bean extract wealthy in chlorogenic acids led to favorable modifications in physique composition in contrast with placebo, though the upper lean mass-to-fat mass ratio seemed to be pushed primarily by fats loss reasonably than a transparent improve in lean mass.

One observational examine confirmed that larger espresso consumption, complete caffeine consumption, or caffeinated espresso alone was positively related to appendicular skeletal muscle mass adjusted for physique mass index (ASMBMI) in a middle-aged United States (US) inhabitants. A separate evaluation recognized a non-linear affiliation between caffeine consumption and ASMI. Different observational research performed in Asian populations reported that espresso consumption was positively related to SM mass or inversely related to low muscle mass or sarcopenia-related outcomes.

Inverse associations between espresso consumption and purposeful impairment or frailty have additionally been reported in older adults. For instance, recurring espresso consumption was related to a decreased danger of frailty in contrast with low espresso consumption amongst European adults aged over 55 years. In a potential examine of older adults (aged ≥ 60 years), consuming at the very least 2 cups of espresso each day was related to a decrease hazard of impaired mobility in contrast with no consumption.

Concluding remarks

Collectively, espresso and a few of its bioactive compounds could modulate organic pathways pertinent to SM metabolism. Nonetheless, out there proof stays inadequate to make causal inferences. Most human proof is observational, whereas many preclinical research use remoted compounds, extracts, or doses that will not mirror recurring espresso consumption.

Moreover, long-term intervention research are wanted, with well-defined exposures and validated SM measures, to find out whether or not espresso and its bioactive compounds have clinically significant results on SM well being in people.