Feeling Sluggish? Support Your Everyday Metabolic Energy

Reviewed by SOMA HEALTH's Medical Research Team

That heavy, sluggish feeling - the sense that your body is running at half speed even when you have technically slept enough - is one of the most common complaints people bring to their own health searches. It is frustrating precisely because it is vague. Understanding where everyday energy actually comes from, at the cellular level, can help you think about it more clearly and act more sensibly.

What 'sluggish' really describes

Sluggishness is a broad, subjective experience: low physical drive, mental fog, a sense of heaviness, and reduced motivation to move. It is not a medical diagnosis, and it rarely has a single cause. Sleep quality, hydration, blood sugar swings, stress, activity level, and diet all feed into how energetic you feel from hour to hour. Because the experience is so general, the most useful first step is usually to examine those everyday inputs rather than reach for a single fix.

Underneath the daily fluctuations sits your metabolism - the sum of the chemical processes that convert food into energy. At the center of that process are mitochondria, the structures inside nearly every cell that produce most of your usable energy from fuel and oxygen. When mitochondria function efficiently, energy-hungry tissues have the fuel they need to perform. When that machinery is under strain, a general sense of low energy can follow.

Mitochondria, metabolism, and cellular energy

Mitochondria are dynamic. Cells continuously build new ones and clear out worn, underperforming units through a housekeeping process called mitophagy - recycling old mitochondria so fresher, more efficient ones can take over. Our guide to what mitophagy is explains this in plain language, and our mitochondrial health overview goes deeper. Human research has connected reduced mitochondrial oxidative capacity to age-related changes in muscle and metabolism, which is one reason cellular energy has become such an active area of study.

This does not mean sluggishness is 'just your mitochondria.' Persistent low energy can also signal thyroid problems, iron deficiency or anemia, sleep disorders such as sleep apnea, depression, blood sugar issues, medication side effects, and more. Those are medical matters. This guide is educational and is not a treatment - if your sluggishness is persistent, worsening, or interfering with daily life, please see your doctor for proper evaluation rather than assuming a supplement is the answer.

Where urolithin A fits in

Urolithin A (UA) is a gut postbiotic. When you eat ellagitannins - polyphenols in pomegranates, walnuts, and some berries - certain gut bacteria can convert them into UA. Only some people carry the microbes needed to make meaningful amounts, which is part of why supplemental UA has attracted attention. You can see dietary sources in our guide to foods high in urolithin A. In laboratory research, UA is studied for supporting mitophagy - the same recycling process that keeps your cellular energy machinery in good repair. For a practical overview, see our guide to urolithin A for energy.

Proven in humans: safety and mitochondrial signals

The most established human evidence is a first-in-human trial by Andreux and colleagues, published in Nature Metabolism in 2019. It reported UA was safe and well tolerated at doses up to 1,000 mg per day, and produced a mitochondrial gene-expression signature in participants - an early, measurable indication the compound engages mitochondria-related pathways. It is worth being precise here: this study measured biological signals, not a subjective 'energy boost.'

Newer human research: function over four months

Later controlled trials focused on physical function. In 2022, Liu, D'Amico and colleagues reported in JAMA Network Open that older adults taking UA over roughly four months saw improvements in aspects of muscle endurance. Singh and colleagues, also in 2022, published a trial in Cell Reports Medicine in middle-aged adults over four months, using 500 mg and 1,000 mg daily arms, and reported effects on muscle strength and exercise performance. A 2024 randomized controlled trial in the Journal of the International Society of Sports Nutrition studied resistance-trained men over eight weeks, and a 2025 trial studied distance runners. A 2025 randomized controlled trial in Nature Aging, over about 28 days, reported support for immune-cell mitochondrial health in midlife adults in the context of inflammaging - the low-grade inflammation associated with aging.

Honesty is essential here, especially around energy. Much of the human research to date measures muscle endurance, strength, and mitochondrial markers rather than the subjective feeling of everyday energy. A 2024 systematic review in Ageing Research Reviews on targeting aging with UA in humans concluded the evidence is still emerging. UA is best understood as supporting normal cellular and mitochondrial function, not as a stimulant or a guaranteed cure for tiredness.

Preclinical research: early and exploratory

Enthusiasm for UA started with animal and cell studies, which generate hypotheses rather than prove human benefit. In a landmark 2016 Nature Medicine paper, Ryu and colleagues reported that UA induced mitophagy, extended lifespan in the roundworm C. elegans, and improved muscle measures in rodents. A 2022 study in Aging Cell by D'Amico and colleagues examined joint and cartilage outcomes in osteoarthritis models. Other tissues often mentioned in coverage - gut, brain, heart, and metabolic tissue - remain areas where early, preclinical research is exploring possible roles, without established human proof. It would be misleading to present any of these as demonstrated human benefits.

Practical guidance for everyday energy

Start with the basics, which carry the strongest evidence: consistent sleep, regular movement, steady hydration, balanced meals that avoid large blood-sugar swings, and stress management. These influence day-to-day energy far more than any supplement. Rule out medical causes with your doctor if sluggishness persists.

Within a healthy foundation, UA is one option some people use to support cellular and mitochondrial health. Human trials have used 500 to 1,000 mg per day, with 1,000 mg at the top of the studied range. For more, see our dosage guide, our full urolithin A guide, and our comparison of the best urolithin A gummies.

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This guide is educational and is not a substitute for advice from a qualified healthcare provider.