Jack Dorsey’s strict wellness regimen sounds extreme, but there’s science to back most of it up.
The billionaire CEO of Twitter TWTR, -0.61% and Square SQ, -0.29% gave a lengthy interview to the “Ben Greenfield Fitness: Diet, Fat Loss and Performance” podcast last month, where he detailed the two-hour meditations, frequent food fasts and alternating saunas and ice baths that he does daily to keep his mind and body healthy. But his personal “biohacking” (or applying tech-hacker ideas to biology to become more productive) went viral last week after several news sites ran stories listing his 11 wellness habits, highlighting that he only eats one meal a day during the week and doesn’t eat at all on weekends.
Dorsey is far from the only CEO to subscribe to a strict diet or fitness plan in pursuit of greatness. Late Apple AAPL, -0.04% co-founder Steve Jobs went through periods of subsisting on just fruit, nuts, seeds, vegetables and grains — including a stint of only eating apples and carrots, according to his biography written by Walter Isaacson. (The book also noted that Jobs stopped wearing deodorant because he said being a fruitarian — or a vegan who eats no animal products whatsoever — flushed his body of mucus, so he no longer had body odor; his colleagues disagreed.)
Elizabeth Holmes’ restrictive diet was also outlined in John Carreyrou’s book “Bad Blood” about the Theranos founder. She fueled her 16-hour work days with a “green juice” of spinach, parsley, wheatgrass, celery and cucumber, and also ate salad without dressing, and oil-free spaghetti tossed with tomatoes. On the flip side, investing legend Warren Buffet has admitted to eating “like a 6-year-old,” including drinking five cans of Coke a day (original or cherry-flavored), as well as sometimes having ice cream for breakfast.
But how healthy are Dorsey’s wellness habits? MarketWatch spoke with medical professionals in nutrition, physical fitness and mental health to break down which of these practices are safe and have science on their side — and which ones you should think twice before trying at home. (No one should begin any kind of diet or fitness program without clearing it with their doctor first.)
Intermittent fasting
Dorsey’s restrictive diet entails only eating between 6:30 and 9 p.m. on weeknights, when his single meal consists of fish, chicken or steak with a salad or side of veggies, with berries or dark chocolate for dessert. He takes supplements during the day, and said, “I feel so much more focused,” and that he’s realized “how much of our days are centered around meals.” He doesn’t eat between Friday evening and Sunday evening at all, and breaks his fast with bone broth.
There is evidence to suggest that intermittent fasting can boost metabolism and burn fat in obese rats, as well as lower blood sugar, blood pressure and cholesterol. And initial human research has found that fasting every other day is as effective for weight loss as eating less every day. But Dorsey is fasting every day, noted Tanya Zuckerbrot, a registered dietitian and founder of the F-Factor Diet. We can’t tell from this interview whether he’s getting his daily nutritional requirements. Many on social media have expressed concern that he has an eating disorder.
“By eating only during the week and fasting on weekends, what Jack is doing is a common form of intermittent fasting, 5:2. This means eating five days normally and fasting two days of the week. However, eating just one meal per day on the eating days arguably is not ‘normal,’” said Zuckerbrot. “Downfalls of fasting include low blood pressure, irritability, headaches, fainting and risk of binge-eating.”
He’s also getting very little carbs and fiber, which has been linked with heart problems and early death. “My two biggest concerns with Jack’s diet is the possible lack of dietary fiber and that it is just not sustainable in the long run,” said Zuckerbrot. Do not attempt this without a doctor’s supervision. The recommended daily diet is around 2,000 calories, but if you want to lose weight, women should still consume between 1,200 to 1,500 calories a day, and men between 1,500 and 1,800 calories.
Meditation
Dorsey meditates twice a day, and works toward getting at least two hours total. “If the goal is mental clarity and focus, then medically there are very few self-care activities out there that have more scientific support for enhancing focus and concentration, and lowering blood pressure and managing stress, than meditation,” Dr. Natalie Dattilo, director of psychology at Brigham and Women’s Hospital, told MarketWatch. “And the good news is that you don’t have to do it for two hours a day to get these benefits.”
So while Dorsey may swear by working toward 120 minutes of mindful breathing and self reflection through meditation in the morning and before bed, even he admitted during the podcast interview that, “if you can just get 10 minutes, and sometimes that’s all I can find, that’s what I do.” Indeed, a 2017 study found that meditating for just 10 minutes a day was enough to see significant results in anxious people finding better focus. Check out a list of meditation apps to get you started here.
Drew Angerer/Getty Images Jack Dorsey seen walking in 2016.Walking to work
Dorsey walks almost five miles to his office at least three times a week, hoofing it for one hour and 15 minutes during his commute. He said the morning constitutional, which allows him to soak up some sun, makes him “feel alive.” A 2014 study also found that workers who changed their commutes from driving to walking or cycling reported feeling better able to concentrate and felt less under strain once the got to the office.
Plus, this morning schlep alone puts him at about the recommended 10,000 steps a day, and closer to the advised 150 minutes of exercise a week. And walking is an inexpensive, low-impact aerobic exercise; someone weighing 150 pounds who walks for an hour would burn around 250 calories.
“Walking is aerobic exercise that helps with strengthening muscles and bone health, and losing weight,” Dr. Gerardo Miranda-Comas, a sports medicine specialist at New York’s Mount Sinai, told MarketWatch. “But we also know that exercise boosts mood. People are at a lower risk of depression if they exercise regularly, so that five-mile walk is meeting the minimum fitness requirements and offering mental health benefits, as well.”
The exercise aids in his sleep, as well. “Studies show that consistent fitness routines have a positive effect on sleep quality and levels of drowsiness. Older adults oftentimes report an improvement in stress and sleep quality when following an appropriate aerobics routine,” said Dr. Sanam Hafeez, a neuropsychologist in New York City.
If you don’t have an extra hour or so to spend walking to work in the morning, or you don’t have access to a safe pedestrian route, simply taking a walk around your building for 30 minutes on your lunch break is a great way to get in some extra steps and work up a sweat, Miranda-Comas said.
High-intensity interval training and seven-minute workouts
Dorsey supplements his walks by sweating with a seven-minute bodystrength workout from the Seven app; there are similar programs on the Johnson & Johnson Official 7 Minute Workout and the 7 Minute Workout Challenge. And he does high-intensity interval training (HIIT) on a stationary bike during the days when he doesn’t walk to work. HIIT entails short bursts of intense exercise (like running sprints or pedaling fast to get the heart pumping) alternated with rest breaks (like walking or pedaling more slowly).
Research shows that HIIT workouts can burn more fat that traditional cardio, and these fat-burning effects linger for hours after you’ve finished these short and intense workouts. “Once you’ve finished exercising, your body goes into post-exercise oxygen consumption, which means your body is going to keep burning calories. So you have benefits even after those seven minutes are up,” said Miranda-Coma.
But it comes with some risks. A recent Rutgers report found that people doing HIIT workouts are at greater risk of injury, especially in the knees and shoulders, stemming from doing burpees, push-ups and lunges, and using the barbells, kettle bells and boxes, that are common to these programs.
Ice baths and saunas
Dorsey alternates between ice baths and hot saunas every night, which he says clears his head. He also begins each day with an ice-cold soak. “Nothing has given me more mental confidence than being able to go straight from room temperature into the cold,” he said, “especially in the morning, going into an ice-cold tub from just being warm in bed is — it just unlocks this thing in my mind and I feel like if I can will myself to do that thing that seems so small but hurts so much, I can do nearly anything.”
He described alternating between a 37-degree ice bath for three minutes followed by sitting in a 220-degree barrel sauna for 15 minutes, and repeating that three times. He’s also added a portable infrared SaunaSpace tent to the mix, which emits near-infrared rays that SaunaSpace claims promote cellular regeneration and detox the body, which helps prevent aging, injuries and illnesses. The research is still inconclusive — after all, while sweat can remove some trace toxins, the liver and kidneys are the real detoxifiers. But the Mayo Clinic notes that no adverse affects have been reported from using infrared saunas.
The theory behind “contrast baths” is that the warmth causes capillaries to open quickly, and the cold causes them to close, and this pumping action decreases swelling and inflammation. “The ice baths have been shown to improve recovery from training. It decreases muscle inflammation, soreness, and promotes healing,” said Miranda-Coma. And regular traditional sauna use has been linked with lowering blood pressure, and reduced risk of stroke, pneumonia and Alzheimer’s. But you could run risks of scalding your skin if the water is too hot, or the opposite if it is too cold. And submerging suddenly in cold water is risky for people with heart problems; the shocking cold puts a strain on the heart.
Journaling before bed
Dorsey ends each day by jotting down his plan to be productive the next day on his iPhone Notes app. “I try to do that every single day, usually when I’m wrapping up the day,” he said. In fact, a recent report found that writing a to-do list before bed can help you fall asleep 10 minutes faster.
“Writing a list of things to do tomorrow is great for reducing worry; if I’m writing down all of the things on my mind, and dumping them on this piece of paper [or in the Notes app], I don’t have to worry about it anymore and I fall asleep,” said Dattilo. “Self-reflection is good for the brain.”
But he might be better off swapping the phone for low-tech pen and paper. Research has also suggested that looking at screens before bed can worsen your sleep quality; the artificial “blue light” delays your body’s internal clock and suppresses the release of the sleep hormone melatonin, which in turn delays the onset of REM sleep and reduces the amount of REM sleep; this less quality sleep makes you feel less alert and more sluggish in the morning.
Sleep monitoring
Dorsey is just as meticulous about his sleep as he is with his waking hours, and he credits many of the above activities (particularly the fasting) with drifting off almost immediately. “I can go to bed and actually knock out in 10 minutes,” he said. He wears an Oura Ring (also favored by Prince Harry) that tracks sleep quality, recovery speed and daily activity. ‘If I keep to a consistent schedule of sleep, I get higher scores on REM and I get much deeper sleep as well,’ he said. Indeed, the National Sleep Foundation advises sticking to the same bedtime and wake up time every day, including the weekends, which regulates your body’s clock and helps you fall asleep and stay asleep for the night.
But tracking your Zs doesn’t guarantee good sleep. “Sleep monitoring is interesting in that it educates us about sleep cycles in an individualized way. It also helps us track our quality of sleep, but unfortunately, things will come up at night that can throw you off,” said Hafeez. “REM sleep could also be interrupted by loud noises at night or some other circumstance. When this happens, sleep monitoring has little effect on the rest you will be getting.”
And no sleep tracker can diagnose a sleep disorder, and none of them are meant to replace speaking with your physician or a sleep specialist if you suspect you are suffering from something like sleep apnea or insomnia. The information that these trackers collect is meant to empower the user to make lifestyle changes by day to rest easier at night.
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