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© Shutterstock
0 / 31 Fotos
What is intermittent fasting? - Intermittent fasting is a broad term encompassing various eating schedules, all cycling between a period of fasting and non-fasting over a defined period. It commonly involves daily 16-hour fasts and 8 hours of eating, called 16/8.
© Shutterstock
1 / 31 Fotos
There are a few variations
- There is also the 5:2 diet, in which you consume only 500-600 calories two days of the week, and eat normally the other five days.
© Shutterstock
2 / 31 Fotos
Weight loss
- IF initially became popular for weight loss. One of the guiding theories is that, along with a calorie reduction, IF can help decrease appetite by slowing the body's metabolism.
© Shutterstock
3 / 31 Fotos
Other benefits - Many also argue that research suggests IF reduces inflammation, balances blood sugar, enhances cell repair, and could increase longevity.
© Shutterstock
4 / 31 Fotos
No strong evidence - A paper in Harvard Health Publishing says that though it's true shedding excess fat will improve a person's metabolic profile and lower cardiovascular risk, there's still no strong evidence.
© Shutterstock
5 / 31 Fotos
You don’t have to count calories - This diet is so attractive because it’s seen as saving both money and time, and it also doesn’t specify which foods you should eat but rather when you should eat them.
© Shutterstock
6 / 31 Fotos
Controversial takes - Some people believe that IF was just made up by millennials who wanted to make themselves feel better about having to skip meals, while others believe it's just a cleverly disguised and socially acceptable form of anorexia.
© Shutterstock
7 / 31 Fotos
Research isn’t as extensive as people think - Many sources claim research “suggests” various benefits, but Harvard Health Publishing stated in 2019 that the studies have been short and limited, and IF has not shown drastically different results compared to normal daily restricting of calories.
© Shutterstock
8 / 31 Fotos
Jennifer Aniston
- Jennifer Aniston revealed that she doesn't eat breakfast, but rather only consumes liquids like coffee and celery juice in the morning, leaving the rest of her eating for the final part of the day.
© Getty Images
9 / 31 Fotos
Kourtney Kardashian - In 2018, Kourtney Kardashian said she's a fan of IF on her app, explaining she wouldn't eat after 7 pm, and would eat breakfast after her workout, around 10:30 am.
© Getty Images
10 / 31 Fotos
Justin Theroux - The actor's trainer reportedly had him eating only between 7 am and 7 pm for a few weeks.
© Getty Images
11 / 31 Fotos
Halle Berry - In 2018, Halle Berry revealed her love for IF on Instagram. Speaking with her personal trainer, she said that she usually eats breakfast around 2 pm, but that she's supplementing her vitamins and nutrients.
© Getty Images
12 / 31 Fotos
Hugh Jackman - The actor has reportedly long been doing a 16-hour fasting period, followed by eight hours where he'll eat.
© Getty Images
13 / 31 Fotos
Scarlett Johansson - For her role as Black Widow, the actress' trainer told Harper's Bazaar that she fasted for around 12 hours each day, and pushed it to 14 or 15 hours depending on her work schedule.
© Getty Images
14 / 31 Fotos
Reese Witherspoon - Witherspoon told Radio Times in 2019 that, like her 'Morning Show' co-star Jennifer Aniston, she only consumes coffee and green juice in the mornings.
© Getty Images
15 / 31 Fotos
Terry Crews - The fit actor has long been a supporter of IF. He reportedly starts his day at 4:45 am, works out at 6 am, and doesn't eat until 2 pm, explaining that he drinks four to five bottles of water with amino acids in that time period.
© Getty Images
16 / 31 Fotos
Vanessa Hudgens - In 2019, actress Vanessa Hudgens revealed that she's a fan of the 16/8 variation, telling Popsugar that she felt clearer and more energized when she started, but also adding, "It's rough, it's no joke. I'm not gonna lie and say it's easy."
© Getty Images
17 / 31 Fotos
Benedict Cumberbatch - The actor follows the 5:2 diet, meaning two days a week he eats only about 500-600 calories.
© Getty Images
18 / 31 Fotos
Mindy Kaling
- The hilarious actress and writer has apparently tried IF, tweeting in 2018: "16:8 more like 16 hate."
© Getty Images
19 / 31 Fotos
Jack Dorsey - The Twitter CEO took things too far for many people, only eating one very basic meal a day between 6:30 and 9:30 pm, and fasting the whole weekend. Many said this wasn’t wellness, but rather an eating disorder.
© Getty Images
20 / 31 Fotos
Not sustainable long-term
- Many people find they feel great at first, but struggle after a little while. IF is not recommended as a long-term diet, and it has the potential to mess up your fitness journey.
© Shutterstock
21 / 31 Fotos
Celeb nutritionists have weighed in
- "Intermittent fasting supports metabolic markers," celebrity nutritionist Kelly LeVeque told E! News, "it lowers glucose, insulin, triglycerides and increases insulin sensitivity."
© Shutterstock
22 / 31 Fotos
Why celebrities love it but you probably won’t - Unless you're trying IF with professional assistance (a personal chef, nutritionist, etc.) to plan well-balanced meals, you're unlikely to hit your daily nutritional needs.
© Shutterstock
23 / 31 Fotos
If you want to try it, you have to start slow - First and foremost, consult a doctor to make sure this is a viable option for you. Then, start by eating your dinners earlier, or delaying breakfast a few days of the week.
© Shutterstock
24 / 31 Fotos
You can’t actually eat whatever you want - To get the benefits of IF, it’s even more important to eat nutritious food. Breaking a fast with unhealthy, high glycemic foods causes a higher increase in inflammatory markers and blood sugar, AKA the opposite of what IF boasts.
© Shutterstock
25 / 31 Fotos
You risk losing touch with hunger/fullness cues - According to Shape, many people who try IF start to lose touch with their hunger and fullness cues, making it difficult to establish an overall healthy diet in the long-term.
© Shutterstock
26 / 31 Fotos
You risk going overboard - When you starve yourself, many turn to rewards. So, on the 5-2 plan, people eat more than normal on non-fasting days. Many also turn to binge-eating, since appetite hormones in your brain reportedly go into overdrive when you're deprived of food.
© Shutterstock
27 / 31 Fotos
Consider your schedule - If you go to bed late every night, fasting starting at 6 pm isn’t a good idea. Consider when you get hungry, when you work out, your social life, work schedule, etc.
© Shutterstock
28 / 31 Fotos
Have a strategy - Nutritionists recommend that if you're serious about trying IF in a healthy way, have a plan, perhaps drawn up with a dietitian, so you have something to guide you.
© Shutterstock
29 / 31 Fotos
It’s just not for everyone
- Celeb nutritionist LeVeque warns, "It is not for everybody and you don't want it to get out of hand," adding that extreme IF is associated with eating disorders, food anxiety, and binge eating. See also: The biggest myths about healthy eating
© Shutterstock
30 / 31 Fotos
© Shutterstock
0 / 31 Fotos
What is intermittent fasting? - Intermittent fasting is a broad term encompassing various eating schedules, all cycling between a period of fasting and non-fasting over a defined period. It commonly involves daily 16-hour fasts and 8 hours of eating, called 16/8.
© Shutterstock
1 / 31 Fotos
There are a few variations
- There is also the 5:2 diet, in which you consume only 500-600 calories two days of the week, and eat normally the other five days.
© Shutterstock
2 / 31 Fotos
Weight loss
- IF initially became popular for weight loss. One of the guiding theories is that, along with a calorie reduction, IF can help decrease appetite by slowing the body's metabolism.
© Shutterstock
3 / 31 Fotos
Other benefits - Many also argue that research suggests IF reduces inflammation, balances blood sugar, enhances cell repair, and could increase longevity.
© Shutterstock
4 / 31 Fotos
No strong evidence - A paper in Harvard Health Publishing says that though it's true shedding excess fat will improve a person's metabolic profile and lower cardiovascular risk, there's still no strong evidence.
© Shutterstock
5 / 31 Fotos
You don’t have to count calories - This diet is so attractive because it’s seen as saving both money and time, and it also doesn’t specify which foods you should eat but rather when you should eat them.
© Shutterstock
6 / 31 Fotos
Controversial takes - Some people believe that IF was just made up by millennials who wanted to make themselves feel better about having to skip meals, while others believe it's just a cleverly disguised and socially acceptable form of anorexia.
© Shutterstock
7 / 31 Fotos
Research isn’t as extensive as people think - Many sources claim research “suggests” various benefits, but Harvard Health Publishing stated in 2019 that the studies have been short and limited, and IF has not shown drastically different results compared to normal daily restricting of calories.
© Shutterstock
8 / 31 Fotos
Jennifer Aniston
- Jennifer Aniston revealed that she doesn't eat breakfast, but rather only consumes liquids like coffee and celery juice in the morning, leaving the rest of her eating for the final part of the day.
© Getty Images
9 / 31 Fotos
Kourtney Kardashian - In 2018, Kourtney Kardashian said she's a fan of IF on her app, explaining she wouldn't eat after 7 pm, and would eat breakfast after her workout, around 10:30 am.
© Getty Images
10 / 31 Fotos
Justin Theroux - The actor's trainer reportedly had him eating only between 7 am and 7 pm for a few weeks.
© Getty Images
11 / 31 Fotos
Halle Berry - In 2018, Halle Berry revealed her love for IF on Instagram. Speaking with her personal trainer, she said that she usually eats breakfast around 2 pm, but that she's supplementing her vitamins and nutrients.
© Getty Images
12 / 31 Fotos
Hugh Jackman - The actor has reportedly long been doing a 16-hour fasting period, followed by eight hours where he'll eat.
© Getty Images
13 / 31 Fotos
Scarlett Johansson - For her role as Black Widow, the actress' trainer told Harper's Bazaar that she fasted for around 12 hours each day, and pushed it to 14 or 15 hours depending on her work schedule.
© Getty Images
14 / 31 Fotos
Reese Witherspoon - Witherspoon told Radio Times in 2019 that, like her 'Morning Show' co-star Jennifer Aniston, she only consumes coffee and green juice in the mornings.
© Getty Images
15 / 31 Fotos
Terry Crews - The fit actor has long been a supporter of IF. He reportedly starts his day at 4:45 am, works out at 6 am, and doesn't eat until 2 pm, explaining that he drinks four to five bottles of water with amino acids in that time period.
© Getty Images
16 / 31 Fotos
Vanessa Hudgens - In 2019, actress Vanessa Hudgens revealed that she's a fan of the 16/8 variation, telling Popsugar that she felt clearer and more energized when she started, but also adding, "It's rough, it's no joke. I'm not gonna lie and say it's easy."
© Getty Images
17 / 31 Fotos
Benedict Cumberbatch - The actor follows the 5:2 diet, meaning two days a week he eats only about 500-600 calories.
© Getty Images
18 / 31 Fotos
Mindy Kaling
- The hilarious actress and writer has apparently tried IF, tweeting in 2018: "16:8 more like 16 hate."
© Getty Images
19 / 31 Fotos
Jack Dorsey - The Twitter CEO took things too far for many people, only eating one very basic meal a day between 6:30 and 9:30 pm, and fasting the whole weekend. Many said this wasn’t wellness, but rather an eating disorder.
© Getty Images
20 / 31 Fotos
Not sustainable long-term
- Many people find they feel great at first, but struggle after a little while. IF is not recommended as a long-term diet, and it has the potential to mess up your fitness journey.
© Shutterstock
21 / 31 Fotos
Celeb nutritionists have weighed in
- "Intermittent fasting supports metabolic markers," celebrity nutritionist Kelly LeVeque told E! News, "it lowers glucose, insulin, triglycerides and increases insulin sensitivity."
© Shutterstock
22 / 31 Fotos
Why celebrities love it but you probably won’t - Unless you're trying IF with professional assistance (a personal chef, nutritionist, etc.) to plan well-balanced meals, you're unlikely to hit your daily nutritional needs.
© Shutterstock
23 / 31 Fotos
If you want to try it, you have to start slow - First and foremost, consult a doctor to make sure this is a viable option for you. Then, start by eating your dinners earlier, or delaying breakfast a few days of the week.
© Shutterstock
24 / 31 Fotos
You can’t actually eat whatever you want - To get the benefits of IF, it’s even more important to eat nutritious food. Breaking a fast with unhealthy, high glycemic foods causes a higher increase in inflammatory markers and blood sugar, AKA the opposite of what IF boasts.
© Shutterstock
25 / 31 Fotos
You risk losing touch with hunger/fullness cues - According to Shape, many people who try IF start to lose touch with their hunger and fullness cues, making it difficult to establish an overall healthy diet in the long-term.
© Shutterstock
26 / 31 Fotos
You risk going overboard - When you starve yourself, many turn to rewards. So, on the 5-2 plan, people eat more than normal on non-fasting days. Many also turn to binge-eating, since appetite hormones in your brain reportedly go into overdrive when you're deprived of food.
© Shutterstock
27 / 31 Fotos
Consider your schedule - If you go to bed late every night, fasting starting at 6 pm isn’t a good idea. Consider when you get hungry, when you work out, your social life, work schedule, etc.
© Shutterstock
28 / 31 Fotos
Have a strategy - Nutritionists recommend that if you're serious about trying IF in a healthy way, have a plan, perhaps drawn up with a dietitian, so you have something to guide you.
© Shutterstock
29 / 31 Fotos
It’s just not for everyone
- Celeb nutritionist LeVeque warns, "It is not for everybody and you don't want it to get out of hand," adding that extreme IF is associated with eating disorders, food anxiety, and binge eating. See also: The biggest myths about healthy eating
© Shutterstock
30 / 31 Fotos
Is intermittent fasting dangerous?
A new study has linked the popular diet to high risk of cardiovascular disease
© Shutterstock
If you're the rare person who hasn't heard about intermittent fasting, it's essentially a dieting method of scheduled fasting, restricting your food consumption into a smaller part of the day. It's one of the hottest diet trends in recent years, especially among celebrities—many of whom have claimed it's helped them shed pesky weight. But, as this diet is easily reduced to simply starving yourself a controlled amount every day, many people have strong opinions against the fad. People who partake in IF (intermittent fasting) claim it's a healthier alternative that boasts many other benefits in addition to weight loss.
However, the American Heart Association published a worrying study on March 18, 2024, showing a link between intermittent fasting and a high risk of cardiovascular disease. The shocking report revealed that those who reduced their eating window to eight hours per day were 91% more likely to die of heart disease compared to those who ate over 12-16 hours. Researchers analyzed around 20,000 adults in the US with an average age of 49 for their study.
The participants who already had cardiovascular disease had a 66% higher risk of death from heart disease or stroke. Meanwhile. participants suffering from cancer who ate over 16 hours or more were shown to be less likely to die from the disease. Researchers determined that intermittent fasting didn't reduce the overall risk of death by any cause and was not associated with living longer. While the study was limited in that it relied on self-reported dietary information from participants and didn't focus on other factors that could be influencing their health, the results are still enough to give one pause before embarking on an IF diet.
Click through the gallery to get a better idea of what intermittent fasting involves, which celebrities advocate for it, the controversy surrounding it, and some helpful tips.
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