What is urolithin A and does it work?
Urolithin A appears safe and has shown a modest effect on muscular endurance in some studies, but the hard endpoints fell just short in several studies. Wait for independent research before placing high expectations on it.
You do not produce urolithin A by eating it directly, but by having what you eat fermented in your gut. Bacteria convert compounds from pomegranate, berries and nuts into this molecule. Not everyone can do this: people fall into three groups, and those in the lowest group produce little or no urolithin A, even on a rich diet.
The biological idea behind it is that urolithin A stimulates the removal of damaged energy factories in muscle cells (mitochondria). This so-called mitophagy process was actually measured in both an early safety study and in later randomised studies in humans: the activity of genes that drive this clean-up process rose in muscle tissue. Whether that molecular change also genuinely improves everyday physical performance is a separate question.
Randomised studies in adults aged 65 to 90 show a mixed picture. After two months, participants taking 1000 mg per day scored better on muscular endurance of the hand and leg muscles than the placebo group. However, the six-minute walk distance and peak ATP production in the muscle did not improve significantly. Another study in middle-aged adults found an improvement in muscle strength and oxygen uptake, but there too the primary endpoint (peak muscle power) was not reached significantly. Inflammatory markers did fall.
On the question of safety, doses of 500 and 1000 mg per day over four weeks to four months have been studied without serious adverse effects. That is the most clear-cut finding to date.
An important caveat: virtually all clinical studies have been conducted by or in collaboration with Amazentis SA, the company that sells urolithin A under a brand name. Several authors are employees, founders or shareholders of that company. Independent replication of the results is still largely absent. Broader applications, such as in muscle diseases, have so far only been studied in animal models and cell cultures.
The evidence rests on a handful of randomised studies in humans, supplemented by animal research and cell studies. The human studies focus on safety and muscle function in older and middle-aged adults. The researchers themselves note that the studies are relatively small and that the primary endpoint was not reached significantly in two of the three clinical studies. Almost all clinical studies have been funded or conducted by the company that sells the product; independent replication is largely absent.
What does urolithin A do to your muscles and mitochondria?
Urolithin A shows positive effects on mitochondrial health and muscle strength in small studies, but the evidence is still limited. Larger independent trials are lacking, so treat the promising claims with appropriate scepticism.
Does urolithin A from pomegranate do anything for your muscles and energy?
UA supplements (1000 mg per day) improved muscular endurance in older adults in one study, but do not demonstrably increase the total energy output of the muscles. If you are curious whether it does anything for you, there is sufficient evidence to consider it, but do not expect a miracle cure.
Does creatine help with weight loss?
Creatine is not a slimming aid and is not recommended for fat loss as a primary goal. If you combine it with strength training, your body composition improves modestly: slightly less fat, more muscle mass.
What does creatine do for people over sixty?
Creatine has reasonably well-supported benefits for people over sixty in the areas of muscle strength, muscle mass and memory, especially in combination with strength training. A daily dose of 3 to 5 grams of creatine monohydrate is safe for healthy people.
Does creatine work better with carbohydrates?
Carbohydrates probably increase the uptake of creatine into the muscle cell via insulin, but when compared against a placebo in research this does not translate into better performance. Add carbohydrates if you want to load, but do not automatically count on extra training results.
Does creatine also help ordinary people, not just athletes?
Creatine is not just for athletes. Combined with strength training, it helps older adults gain more muscle strength, and probably also supports better memory.