Longevity doctor Peter Attia takes 1 supplement to offset jet lag when he travels. It's popular with muscle-building athletes, too.

• Dr. Peter Attia is serious about getting good sleep and maintaining muscle mass.
• Both are hard when you're traveling, and the body's circadian rhythms are disrupted.

Dr. Peter Attia doesn't travel anywhere near as much as he used to, pre-COVID, when he was away from home almost half the year.

The California-based doctor and author of the bestselling book "Outlive: The science and art of longevity," said on this week's podcast episode of "The Drive" that he mainly sticks to his at-home medicine cabinet routines these days.

He pops roughly eight different pills plus a multivitamin powder each morning, and typically adds in three more supplements at night. But he doesn't think that you should just go out and copy his highly personalized, and variable, formula.

"It somehow becomes like, I don't know, like a 'well, if Peter does this, this is, you should do this,' or something like that,'" he said.

In reality, not everyone needs Attia's (somewhat pricey) supplements. Even he's changing up his own regimen all the time.

But, he shared the one pill he likes to take whenever he travels, to help with the brain fog and disorientation that can come when your body's circadian rhythms are suddenly plopped into a new time zone.

When Attia travels across multiple time zones, he takes a supplement that contains phosphatidylserine (or, PS)

Attia keeps a stash of phosphatidylserine on hand for travel. He said he uses the Jarrow brand.

"If I'm really going to the trouble of taking it, I'm presumably on a long flight where I'm trying to overcome a significant time zone," Attia said on the podcast. "So I'll usually take about 400 milligrams."

Phosphatidylserine (PS) is a fatty, phosphate-based chemical compound that exists in every cell in our body. It is a critical component of cell membranes, aiding in bringing in nutrients, carting out waste, and helping cells communicate.

We can get some extra phosphatidylserine from eating eggs, fish, or soy, as well as animal organs like the liver.

PS supplements are popular among some athletes and dementia patients

In the past, PS supplements were derived from cow brains. Some small studies suggested those pills might've been somewhat beneficial for older adults managing cognitive decline. (To be clear: this wasn't a cure for diseases like Alzheimer's, the benefits were marginal improvements on some memory tests.) But it's unclear if PS has any brain-booting effects in younger people, since our bodies should already have all the PS they require.

All PS that's made today is manufactured from plants and fish, instead of cow brains, to avoid transmitting mad cow disease to people. The type of PS Attia takes is made from sunflowers. It's not clear that such plant-based PS pills have the same beneficial memory-boosting effects that cow-based PS once did for people.

Athletes sometimes take up to 800 mg of PS a day in the hopes it will help them build more muscle, but the data on this idea is also mixed. PS can help slow down and regulate our body's release of cortisol, a stress hormone which can spike when we travel and don't get good, consistent sleep.

Some people should avoid PS supplements

Attia's big caveat to all of this is that you should be careful, thoughtful, and judicious about any supplements you may take, always evaluating how you're feeling, what your doctor and lab results say, and using common sense.

Some pills can have harmful interactions with the drugs people are already on, or the conditions they have, which may be undiagnosed.

Taking phosphatidylserine with blood thinners, for example, can be dangerous, and side effects can include an upset stomach, rash, headache, or low blood sugar. People with a shellfish allergy should also make sure they don't take fish-based phosphatidylserine supplements.

You can fight jet lag without supplements, too

If you want to reduce jet lag without supplements, experts recommend shifting your sleeping patterns slightly in the days before you fly, perhaps going to bed an hour earlier or later each day, depending on your direction of travel.

Getting enough light during the daytime and darkness at night also helps. So does avoiding caffeine, staying well-hydrated, and, possibly, drinking some tart cherry juice.