Can Taurine or Other Supplements Keep You Cool in the Heat?

This Week’s Research Highlight

Background

When it gets hot outside, humans rely on sweating to get rid of excess heat. Failure to do that and core temperature drifts upward. This can lead to heat exhaustion, or worse, heat stroke. Endurance training and heat acclimation help. To complicate matters, half of U.S. adults also take dietary supplements. Some ingredients are suspected to worsen heat‑stress while others might be protective. However, nobody had tallied the evidence across all supplements, exercise and rest conditions, and different environments, until now.

This topic hits close to home. Austin, where I live, is known for inhumanely hot summers, and now that it’s May, temperatures are climbing.

wo weekends ago, my 11-year-old son did a workout and then spent the afternoon playing pickup soccer at a field next to Meanwhile Brewery. After the tough training session, he kept pushing hard in the sun. When he rejoined us at the table, he looked off—restless and woozy. As I watched him, a nurse at a nearby table noticed, too. He asked whether my son was okay, then darted off to get ice packs. We tucked the packs under his arms and behind his neck and sat with him for a few minutes. He remained agitated, so we rushed him to urgent care. His temperature and heart rate were high, and he was anxious and uncomfortable. The staff monitored him, gave him Gatorade, and after about 90 minutes diagnosed him with heat exhaustion. Thankfully, it wasn’t heatstroke, but it was still very serious and scary for all of us.

Once the episode passed, he had no lingering issues except fatigue for the rest of the day. By the next morning, it was as if nothing had happened; he felt perfectly normal.

My son has followed this routine—practice, then pickup games at Meanwhile—at least ten times, sometimes in even hotter weather. The incident, however, reminded us that heat stress can strike anyone, even during familiar activities.

As we head into the summer months in the Western Hemisphere, keep a close eye on yourself and your loved ones. With that in mind, let’s dig into today’s study to see which supplements might improve tolerance to heat stress.

What did the researchers set out to do?

In this newsletter, we cover a study led by Jennifer Peel of Swansea University in the United Kingdom, published in the American Journal of Physiology. The team set out to map the evidence landscape on supplements and heat stress. Their first goal was to capture every randomized trial conducted in hot conditions—defined as air temperatures of at least 86°F (30°C) or wet-bulb globe temperatures of 68°F (20°C) or higher—that tracked both a dietary supplement and either core temperature or sweating.

Next, they quantified how each supplement affected three concrete outcomes:

1. The highest core temperature reached.
2. Total body sweat produced per minute.
3. The sweat rate measured at a single skin site.

Finally, they intended to uncover whether factors such as a participant’s fitness, heat-acclimation status, hydration strategy, fluid intake during the trial, session length, or the exact severity of the environment modified any of those effects.

Peel’s team sifted through 39,000+ records (PubMed, SPORTDiscus, Scopus) and social-media leads on 9 Apr 2024, retaining only placebo-controlled hot-environment trials on orally ingested supplements in healthy adults. The final 124 papers—each using crossover or parallel designs—covered 1,553 participants and provided 135 core-temperature, 106 whole-body sweat, and 11 local sweat comparisons.

Which supplements made the cut in the analysis?

A grand total of thirty‑nine distinct products or blends were included. Those products are categorized here:

What were the main findings?

On core temperature

Most ingredients or formulations—creatine, nitrate, l-arginine, betaine, sodium citrate, glycerol, vitamin C— barely moved the needle, yet some ingredients did. Caffeine edged core heat upward, and pairing it with ginseng amplified that rise dramatically. This is important because the most common pre-workout ergogenic—performance enhancing ingredient— is caffeine, whether it’s as a cup of coffee, or included in a mixed powder, gel block, or pill. So, one lesson here is to be careful with your caffeine consumption when you’re exercising in hot environments.

I have taken ginseng before hot yoga for years 😬, but have lived to tell about it!

In contrast, taurine (a big dose of 50 mg/kg), as well as the lychee-derived polyphenol, Oligonol, cooled core temperature to a meaningful degree. Catechin’s, too, might also prevent a raise in core temperature, but the data for this was not as solid.

Taurine Dose Illustrations: 
To replicate this effect of a 50 mg / kg dose of taurine:

A 210 lb man (or  95 kg) 
Would take 4.8 grams of taurine 1 hour before exercise.

A 140 lb women (or  35 kg) 
Would take 1.75 grams of taurine 1 hour before exercise.

On sweating

For sweat output, nearly every supplement left whole-body and local sweating unchanged. A handful, though, did have an effect.

Again, a hefty dose of taurine make people sweat sooner and more, pumping out 13–27 % more fluid, boosting evaporative cooling. Hyper-hydration blends of creatine plus glycerol also nudged sweat rate up a notch.

Some products made people sweat less. GABA sharply sweat cut output by reducing metabolic heat. And perhaps most unexpectedly, whey protein (15 g) reduced whole-body sweating, though we still don’t know why.

Do fitness, acclimation, hydration, or trial design matter?

The supplements acted the same no matter who you were or how you trained. Heat-acclimation, hydration, workout length, and even the day’s Wet Bulb Globe Temperature (WBGT) didn’t tilt the results, so any boost—or drawback—comes from the ingredient itself, not these usual variables.

Wet Bulb Globe Temperature (WBGT)

It’s a heat-stress index that rolls four factors into one number:

What’s Measured	Sensor Used	Why It Matters
Humidity + air temperature	Wet-bulb thermometer	Shows how well sweat can evaporate (main cooling path).
Direct solar radiation	Black-globe thermometer	Captures heat added by sunlight.
Plain air temperature	Dry-bulb thermometer	Baseline air heat.

Higher WBGT leads to a greater risk of heat illness. Sports bodies, military units, and workplaces set activity limits and hydration plans based on WBGT thresholds instead of simple air temperature, because it better reflects the true physiological load on the body.

Example guidance for outdoor SPORTS practice

WBGT	Heat-risk flag*	Typical guidance for outdoor SPORTS practice†
< 82 ° F < 28 ° F	Green	Normal training ≥3 short (≥3 min) shade/water breaks per hour
82 – 86.9 ° F 28 – 30.4 ° C	Yellow	Use discretion with intense or prolonged drills ≥3 breaks (≥4 min each)
87 – 89.9 ° F 30.5 – 32.1 ° C	Orange	Max practice 2 h Football limited to helmet + shoulder pads ≥4 breaks (≥4 min)
90 – 92 ° F 32.2 – 33.3 ° C	Red	Max practice 1 h No protective equipment or conditioning 20 min total rest
> 92.1 ° F > 33.3 ° C	Black	Cancel Move indoors Or delay until cooler conditions

• Flag colors follow the National Athletic Trainers’ Association (NATA) convention.

†Adapted from NATA’s exertional-heat-illness guidelines for high-school and collegiate athletes.

Example work/rest limits for occupational tasks

U.S. Army TB MED 507

Heat Cat.	WBGT (°F)	Easy work	Moderate work	Hard work
1 (White)	78 – 81.9	No limit / 0.5 qt h⁻¹	No limit / 0.75 qt h⁻¹	40 min work / 20 min rest / 0.75 qt h⁻¹
2 (Green)	82 – 84.9	No limit / 0.5	50 / 10 / 0.75	30 / 30 / 1
3 (Yellow)	85 – 87.9	No limit / 0.75	40 / 20 / 0.75	30 / 30 / 1
4 (Red)	88 – 89.9	No limit / 0.75	30 / 30 / 0.75	20 / 40 / 1
5 (Black)	> 90	50 / 10 / 1	20 / 40 / 1	10 / 50 / 1

Work/rest = minutes of work / rest each hour; water needs shown in quarts per hour for a heat-acclimated, average-size worker in standard uniform.

Which supplements look helpful right now?

Taurine taken an hour before the heat kicks evaporation into high gear, though the evidence rests on just two studies and could vanish with better data. But, I’d say that taurine deserves a closer look by the research community. Also, it seems to provide that sweet spot effect—earlier, heavier sweating and a cooler core, without cardiovascular downsides.

Hyperhydrateing might also provide a useful strategy to stay cooler in the heat. Try creatine with ≈1.4 g/kg glycerol before exercising but keep in mind, while hydration strategies matter, hyper‑hydrating agents appear to work inconsistently. For instance, creatine and glycerol is promising, but glycerol alone, even at very high doses, isn’t.

If you’d rather drop core temperature to avoid looking like a sweaty mess (like I do after hot yogav), 100-200 mg of the lychee-polyphenol Oligonol taken 30–60 minutes might do the trick, as it has in passive-heat tests. But while oligonol, and maybe catechin, look interesting, regular high‑dose polyphenols could blunt heat‑adaptation signaling, which would slow your acclimatization to heat. Finally, one gram of GABA right before exercise calms the brain’s heat drive, curbing metabolic heat, but also diminishes sweat rate, too. Therefore, these strategy might be beneficial for competition in a hot environment, but not as a part of one’s regular training regimen. However, if you are an athlete, and curious to investigate this strategy, be sure to test your reaction to these compounds before your competition so you know how they affect you.

Remember, the real goal isn’t to sweat less—it’s to keep your core temperature in check so you can maintain performance and avoid dangerous conditions like heat stress or heat exhaustion.

Take‑home  message

For now, treat heat like a performance variable you can partly control. Skip or cut back on caffeine before hot‑weather activity, consider a taurine trial run, and use creatine‑plus‑glycerol preloads if you need extra fluid on board. Most other supplements neither help nor harm, but the book is still being written—stay tuned as new data roll in.

Summary: Researchers analyzed 124 placebo-controlled trials to examine how supplements affect heat tolerance in hot conditions (≥86°F/30°C). The study evaluated supplements' impact on core temperature and sweating rates. Key findings revealed that taurine (50mg/kg) and Oligonol effectively lowered core temperature, while caffeine increased it - especially when combined with ginseng. Taurine also increased sweating by 13-27%, enhancing cooling. Interestingly, GABA and whey protein reduced sweating. The effects were consistent regardless of fitness level, heat acclimatization, or hydration status. This suggests the supplements' effects come from the ingredients themselves rather than other variables.

Random Trivia & Weird News

Over a century ago, at the 1904 St. Louis Olympics, Californian distance runner William García offered physiologists an unexpected lesson in heat balance. The 90 °F sun turned the dirt road into airborne grit; every breath coated García’s throat and bronchi with fine dust. Mid-race his core temperature rocketed above 105 °F, yet spectators noted that his skin stayed eerily dry—he had stopped sweating. Doctors later realized that evaporative cooling from the lungs—not just your skin—contributes notably to total heat loss. By clogging his airways, the dust had sealed off that exhaled water-vapor route to contribute to cooling his body. Incidentally, this is also why dehydration, asthma, or even a tight face mask can hasten heat exhaustion: each narrows a pathway for vapor to escape, tipping the body toward dangerous overheating.

Podcasts We Loved This Week

• Derek Thompson: Megapod: The Crisis in American Science. Via Plane English.

• Greg Potter, PhD: Longevity Supplements: NR, NMN, Astaxanthin, AKG, Glycine, GlyNAC, Ergothioneine | Siim Land and Nic Verhoeven. Via Reason & Well-being.

Products We Like

Taurine

Taurine isn’t an essential nutrient—healthy people don’t need to worry about deficiency. The average American diet provides 120–180 mg per day, and the body can make small amounts on its own.

But the benefits seen in studies—whether for improving metabolic health or enhancing heat tolerance—come from much higher doses than diet alone provides. For metabolic effects, most studies used between 1.5 and 6 grams per day. A safe and practical long-term dose is 3 grams daily, which you can split into 1 gram taken three times per day: morning, afternoon, and evening. For heat stress, studies showing meaningful cooling effects used a single dose of 50 mg/kg taken one hour before heat exposure—equivalent to about 3.5 grams for a 70-kg (154-lb) person.

humanOS Catalog Feature of the Week

Heart Health — from The Mediterranean Diet

Taurine may be a secret key to the robust health of people following traditional Mediterranean diets. When researchers examined urinary taurine levels and cardiovascular mortality in people around the world, they found that the populations with the highest taurine levels were in Japan and around the Mediterranean region.

However, it is certainly not the only factor at play.

In this lesson, we dig into some of the diet trials that began to reveal how and why the traditional Mediterranean diet is associated with better heart health. And if you go a little further into the course, you can also get some insight into specific dietary components.

Wishing you the best,