15 Celebrities Who’ve Tried the Keto Diet (and How It Worked for Them)

The high-fat, ultra-low-carb diet has gotten a boost by being endorsed by several famous faces.

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Melissa McCarthy,  Al Roker, Savannah Guthrie

Melissa McCarthy, Al Roker, and Savannah Guthrie are among the celebrities who have used the popular ketogenic diet to drop unwanted pounds.

Celebrities didn’t start the ketogenic, or keto, diet trend, but they’ve certainly added fuel to the already-hot fire. The eating plan has skyrocketed in popularity in recent years, and that could be due in part to its being embraced by several actors, sports stars, and reality TV stars.

The ketogenic diet is a low-carb plan to the extreme. Followers of a common version of the diet source around 75 percent of their daily calories from fat, up to 20 percent from protein (no more, as this can kick the body out of ketosis), and just 5 percent from carbohydrates. All it takes is a few days of eating this way for the body to enter ketosis, which essentially means the body starts burning fat instead of glucose (carbohydrates) for fuel.

RELATED: Everything to Eat and Avoid on the Ketogenic Diet

The keto diet has been shown to have many health benefits, most notably short-term weight loss. Low-calorie ketogenic diets may help people who are overweight or have obesity reduce their body mass index and decrease their waist circumference, according to a review and meta-analysis published in March 2020 in Reviews in Endocrine & Metabolic Disorders. Additional studies on the long-term effects of the ketogenic diet on weight loss are needed.

There is also evidence that the low-carb, high-fat eating plan may help improve outcomes for people with type 2 diabetes. In one trial, people with type 2 diabetes who followed a ketogenic diet for two years were able to decrease their use of diabetes medications by 81 percent, while those in a control group increased their medication during the same time span, according to research published in 2019 in Frontiers in Endocrinology.

Early research in rodents indicates that following a ketogenic diet may even help you live longer, according to research published in June 2022 in Cell Metabolism, although further research is needed to see if similar effects are observed in humans.

Despite those potential payoffs, cutting carbs so drastically isn’t easy. Some celebs refreshingly admit to having the same troubles that everyone else experiences on the diet when starting out (commonly known as “the keto flu”), including irritability and headaches. Here are 15 stars who’ve tried or endorsed the keto diet.


Katie Couric

katie couric, a celebrity who follows the ketogenic diet

In August 2018, the then 61-year-old former Today show anchor posted on her Instagram Stories that a week into the diet she did “feel better” but hinted that she'd experienced some symptoms of the keto flu, Women's Health reported. “The fourth or fifth day, I felt a little shaky and headachy, but I feel much better,” Couric said. Suffice to say, the mother of two enjoyed incorporating more fat into her diet. “I’m eating mostly protein and some cheese," she said. “And I'm putting half-and-half in my iced coffee, and I gotta tell ya, it’s damn good." Since then, Couric, now 66, has moved on to other diets, including the pegan diet — a combination of paleo and vegan created by functional medicine specialist Mark Hyman, MD, per the Cleveland Clinic. She posted on Instagram: “Feeling good after almost a week on the Pegan reset … I need some new recipes for breakfast and not eggs. Any ideas?”


Halle Berry

Halle Berry, a celebrity who follows the ketogenic diet

The 56-year-old actress hasn’t been shy about her love for the keto diet. As Insider reported in 2021, Berry has been on the keto diet for 30 years as a way to manage diabetes. She also told People in 2018 that she’s a big meat eater and doesn’t fill up on pasta or anything with added sugar, making her a good candidate for keto. Instead, she fills her plate with healthy fats, including avocados.

RELATED: All the Benefits and Risks of Going Keto You Need to Know


Kourtney Kardashian

kourtney kardashian, a celebrity who follows the ketogenic diet

Kourtney is considered among the healthiest of the Kardashian bunch. According to a People story from February 2018, she shared in her app that going keto was a “really positive experience.” She eats cauliflower rice or broccoli rice in place of carbs. But just because she’s a reality TV star doesn’t make her immune to the negative side effects associated with this way of eating. Kardashian suffered from headaches and low energy for a couple of weeks and makes the diet more sustainable by practicing it for brief periods, per Poosh, her online guide to healthy living.


Kim Kardashian

Kim Kardashian, a celebrity who follows the ketogenic diet

Kourtney’s not the only Kardashian who’s been a devotee of the low-carb lifestyle. Kim jumped on the bandwagon, too. According to a story published in December 2020 in People, she reportedly lost 60 pounds (lbs) after having her son Saint while on the Atkins 40 diet. Atkins 40, a version of the Atkins diet that is designed for people with less than 40 pounds to lose, has been around since the 1970s. Like the ketogenic diet, Atkins involves a very limited intake of carbs and high amounts of fat. The main difference is that on the Atkins diet, you’ll slowly reintroduce carbs, so ketosis will likely only come into play during phase 1.


Gwyneth Paltrow

gwenyth paltrow, a celebrity who follows the ketogenic diet

Paltrow, the founder of wellness lifestyle brand Goop, has been criticized for doling out pretty wacky health advice in the past, including her claims about the benefits of the keto diet. According to a 2021 Insider story, the 50-year-old actress and business mogul followed a vegan keto diet to detox and ease lingering COVID-19 symptoms like fatigue and brain fog, though experts say there’s little evidence that her nutrition strategies will help.

RELATED: 8 Steps Beginners Should Take Before Trying the Ketogenic Diet


LeBron James

lebron james, a celebrity who follows the ketogenic diet

Flash back to the summer of 2014 when the baller slimmed down his 6-foot-8-inch-tall frame. When James showed off a six-pack in a series of Instagram posts, everyone got buzzing about what changes he’d been making. Dozens of news stories revealed that the keto diet was the major reason. He told Sports Illustrated that he didn’t eat dairy, sugar, or carbohydrates for 67 days. The reasoning? To “test his mental fortitude.” Some outlets, including Business Insider, speculated that he was trying to follow Kobe Bryant, who lost weight in his mid-thirties and ended up giving his career a second wind.


Vinny Guadagnino

vinny guadagnino, a celebrity who follows the ketogenic diet

Guadagnino came back into the spotlight in 2018 with the reboot of MTV’s hit reality TV show Jersey Shore, this time called Jersey Shore Family Reunion. In May 2018, PopSugar reported that in the years since the MTV show aired, Guadagnino adopted the keto diet and launched a dedicated Instagram account where he goes by @ketoguido. In 2019, he released The Keto Guido Cookbook, featuring over 100 keto recipes and a seven-day keto diet meal plan. According to a March 2018 Instagram post, Guadagnino's old way of eating had him 50 lbs heavier and looking 10 years older.


Megan Fox

megan fox, a celebrity who follows the ketogenic diet

The Transformers actress and mom of three turned to the keto diet to get her pre-baby body back. Fox told E! News that she cut out bread and carbs, including chips, pretzels, and crackers. She cleaned up her diet so much that the worst thing she’d take in on any given day was coffee, admitting to The View: “I don’t eat anything fun.”


Adriana Lima

adriana lima, a celebrity who follows the ketogenic diet

What does it take to get the body of a Victoria’s Secret angel? This supermodel went on a low-carb diet and did two-hour workouts each day to prep for the Victoria’s Secret Fashion Show a few years ago, according to an article from The Cut. Her diet was primarily made up of green veggies, protein, and protein shakes or cereal bars as snacks. Since then, it seems she’s stuck to a keto diet, according to a story published in July 2018 in Insider.


Alicia Vikander

alicia vikander, a celebrity who follows the ketogenic diet

Vikander adopted the keto diet two months before shooting began for her role as Lara Croft in Tomb Raider. According to a March 2018 article in Women’s Health Australia, Vikander’s trainer, Magnus Lygdback, could tell Vikander was struggling a bit in the beginning, but thanks to her solid willpower, she stuck to it. She stocked up on fish for protein; MCT oil, coconut oil, and avocados for fat; and plenty of low-carb veggies while filming the 2018 blockbuster.

RELATED: The Possible Short- and Long-Term Effects of the Ketogenic Diet


Vanessa Hudgens

vanessa hudgens, a celebrity who follows the ketogenic diet

Hudgens doesn’t shy away from bacon. It’s all part of the High School Musical actress and singer’s keto diet plan, which she says helped her drop 20 lbs from her 5-foot-2-inch-tall frame in 2017 (in addition to the twice-a-day SoulCycle sessions, that is). Since then, she’s started intermittent fasting, saving the more flexible keto diet for days when she works long hours, reported a March 2021 article in Eat This, Not That! “I’m always making sure I’m getting those healthy fats in, so I eat a LOT of almond butter. You feel really energetic and supported on the keto diet,” she told People in April 2019.


Tim Tebow

tim tebow, a celebrity who follows the ketogenic diet

The former professional athlete told GQ in February 2017 that he followed the keto diet and avocados were his favorite source of fat, eating about four a day in everything from guacamole to smoothies. He rounds out his diet with eggs, sea bass, steak, and vegetables like asparagus. Peep his keto tips and seven-day keto meal plan on KetoLogic.


Al Roker


In March 2019, the Today co-anchor shared that he’d lost 40 lbs after following the keto diet for several months. Apparently, the low-carb eating plan also had positive effects on his cholesterol numbers. “My cholesterol — just had them checked a couple of weeks ago. Everything’s good,” he said on the show while cooking a sloppy Joe recipe he likes to pair with a keto-friendly bread recipe. As of June 2022, Roker is still following a low-carb eating plan, although it is no longer strictly keto. Thanks to daily walks and a diet that caps carbs to 100 grams per day, the weatherman shed 45 pounds over several months, he revealed on the show.


Melissa McCarthy


The comedian lost a whopping 75 lbs by following a keto diet and taking up martial arts, reported a July 2020 article in Life & Style. Unlike other celebrities, McCarthy doesn’t believe in fad diets, severe calorie restriction, or obsession with exercise. Instead, she relies on nutrient-rich foods like lean protein, fiber, healthy fats, and tons of fruits and veggies, notes a July 2022 article in Parade. But The Bridesmaids actress isn’t interested in talking about her body: “My message is that as long as everybody’s healthy, enjoy and embrace whatever body type you have,” per the Life & Style piece.


Savannah Guthrie


Evidently, the keto diet has been making the rounds among Today mainstays. Co-host Guthrie gave the low-carb, high-fat lifestyle a try in 2018. But, per a November 2018 Women’s Health article, Guthrie’s results weren’t entirely positive. While keto seemed to make her feel mentally sharper, it sapped her energy for workouts and led to zero weight loss after a few months. The one positive? She enjoyed eating plenty of bacon, per a November 2018 People article.