6 Celebrity Diet Trends Backed by Science

Are you looking for diet trends that are not just endorsed by celebrities but also backed by scientific research? Look no further. Here we delve into seven celebrity diet trends that have gained popularity in recent years and are supported by scientific evidence. From plant-based and vegan diets (championed by the likes of Lizzo) to intermittent fasting (like Jennifer Aniston, who has said she skips breakfast), we explore the benefits and potential drawbacks of each trend, as well as the celebrities who swear by them. Better yet, we asked dietitians to help us determine if these trends are just fads or actual, sustainable meal plans backed by science. The Mediterranean Diet, for example, "focuses on balance," says sports performance dietitian Destini Moody, RD, CSSD, LD, while "plant-based diets are typically rich in fiber, antioxidants, vitamins, and minerals," says Mary Sabat, MS, RDN, LD. Read on for the list of the full six.

Plant-Based Diet

The Pros: The number of celebrities who adhere to a plant-based diet is growing—and for good reason. Paul McCartney, Carrie Underwood, Milo Ventimiglia and a slew of others are among the celebs who embrace the plant-based life. (It's worth noting that although many people assume plant-based is just another term for vegan, they're not exactly the same. While vegans eliminate any and all animal products, a plant-based diet is one that focuses primarily on fruits, vegetables, nuts, and other plant-based foods, but does not necessarily shun all animal products completely.) "A review has shown that people who adhere to plant-based diets have been proven to lengthen life and drastically reduce the risk of chronic diseases, including heart disease, diabetes, and obesity," says Moody. "Under the supervision of a physician and a dietitian, the diet is also effective for reducing dosages of medications or eliminating the need for specific medications, according to the review," she adds. 

And that's not all. "Research has shown that individuals following a plant-based diet tend to have a lower risk of developing chronic conditions such as heart disease, type 2 diabetes, obesity, and certain types of cancer," says Sabat. "Plant-based diets are typically rich in fiber, antioxidants, vitamins, and minerals while being lower in saturated fats and cholesterol. These factors contribute to improved overall health and a reduced risk of various diseases."

The Cons: One frequently cited concern about a vegan diet is protein, and making sure you're getting enough of it. But there are ways to alleviate that issue. Protein powders, certain vegetables, beans, nuts, seeds, and whole grains are great sources.

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The Mediterranean Diet

The Pros: The Mediterranean diet isn't exactly a diet—it's more of a lifestyle because there are no hard rules about mealtimes or portions. Instead, it centers around foods traditionally eaten in countries bordering the Mediterranean Sea and consists of fruits, vegetables, legumes, nuts, olive oil, and fish that are low in processed carbs, sugars, and dairy. Gal Gadot, John Goodman, Kayla Itsines, Brooke Burke, and many others swear by the diet. Hailed as the best diet in the world by US News for six consecutive years, the healthy lifestyle offers plenty of benefits. "The Mediterranean diet is exceptionally high in antioxidants and polyphenols, which a 2022 meta-analysis has shown is very effective at maintaining a high level of health. It has been shown that people who adhere to this diet have the lowest incidences of obesity and chronic disease," Moody explains. "Mediterranean diets emphasize overall diet quality over specific nutrients or food groups. So, unlike the diets famous for telling you what to eliminate, the Mediterranean diet focuses on balance."

Sabat adds, "Studies have shown that adhering to this eating pattern can lower the risk of heart disease, stroke, type 2 diabetes, certain cancers, and overall mortality. The diet's emphasis on whole foods, healthy fats (such as monounsaturated fats from olive oil), antioxidants, and fiber contribute to its favorable effects on health."

The Cons: None, really.

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Intermittent Fasting

The Pros: With intermittent fasting, there's no reading an ingredients list and no counting calories. You restrict what time of day you eat and how many hours you build in between meals. Jennifer Aniston, Terry Crews, Scarlett Johansson, and Mark Wahlberg have all talked about the benefits of fasting and experts agree that it can be effective. "Intermittent fasting has been supported by scientific studies as a viable approach for weight loss and improving metabolic health," Sabat says. "It can lead to a reduction in calorie intake and promote weight loss, primarily by enhancing fat burning and increasing insulin sensitivity. Intermittent fasting has also shown potential benefits for brain health, longevity, and cellular repair, although further research is needed in these areas."

Cons: While intermittent fasting has its benefits, there are some potential drawbacks to consider. Firstly, adhering to strict fasting windows can be challenging for some individuals, leading to feelings of hunger, irritability, and difficulty concentrating. Moreover, fasting for extended periods may result in muscle loss along with fat loss, which can be detrimental to overall body composition. Consulting with a healthcare professional is recommended before starting intermittent fasting.

Paleo Diet

Pros: Danica Patrick is among the famous believers in the paleo diet, which "focuses on consuming lean meats, fish, fruits, vegetables, nuts, and seeds while excluding grains, legumes, dairy products, processed foods, and added sugars," Sabat says. Patrick credits the diet for turning her life around, writing: "The longer I have eaten like this, the more I have thought about it, and it's become clear: It's all about eating real food!!!!!!" 

"One large study looked at the benefits of self-reported, long-term dietary patterns in young adults from Spain. The researchers found that the paleo diet was linked to lower heart disease, or cardiovascular, risk factors. The lower risk mostly came from avoiding highly processed foods, such as chips and candy, and eating lots of fruits and vegetables," says the Mayo Clinic, which adds that "longer trials with large groups of people randomly assigned to different diets are needed to understand the long-term, overall health benefits and possible risks of a paleo diet."

Cons: According to Sabat, the studies are encouraging but not a slam dunk. "While the paleo diet has gained popularity, the scientific evidence supporting its benefits is limited and mixed. While some studies suggest that a paleo-style eating pattern can lead to weight loss, improved glucose control, and reduced risk factors for heart disease, other research indicates potential concerns, such as nutrient deficiencies due to the exclusion of certain food groups. It is important to note that the concept of a 'paleo' diet is based on assumptions about our ancestors' eating habits, and these assumptions may not accurately reflect historical dietary patterns."

Paleo for Beginners

A Vegan Diet

Pros: Vegan diets have been found to be abundant in essential nutrients such as potassium, magnesium, and folate, as well as vitamins A, C, and E. Numerous studies have consistently shown that vegan diets are generally higher in fiber, antioxidants, and beneficial plant compounds, which contribute to improved overall health.

Woody Harrelson has been vegan for over 30 years. He invests in vegan brands, advocates for animal rights and climate change, and is an investor in vegan restaurants like Sage in Los Angeles. To say he's committed is an understatement. The actor has been eating raw for quite some time and loves the way he feels. "I eat vegan, but I eat mostly raw," he told InStyle. "If I have a cooked meal, I feel my energy drop." 

Cons: While a vegan diet can have numerous health benefits, there are some potential drawbacks to consider. One concern is the risk of nutrient deficiencies, particularly in vitamins like B12, iron, zinc, and omega-3 fatty acids, which are predominantly found in animal-based foods. Vegans may need to pay extra attention to ensure they obtain adequate amounts of these nutrients through fortified foods or supplements.  

As for a raw diet like Harrelson's, Sabat says, "While a raw food diet can increase the intake of fruits and vegetables, providing essential nutrients and antioxidants, the scientific evidence supporting its overall health benefits is limited. Some studies suggest that a raw food diet can lead to weight loss and improvements in certain health markers, such as blood pressure and cholesterol levels. However, it is important to note that a raw food diet may also increase the risk of nutrient deficiencies and pose challenges in meeting all nutritional needs."

Keto Diet

Pros: Several stars including Halle Berry, Kourtney Kardashian, and Alicia Vikander have all been on the high-fat, moderate-protein, and low-carb diet known as keto. But while celebrities may embrace keto, the verdict among experts is mixed. "The keto diet is backed by scientific research in various areas," Sabat tells us. "Studies have shown that the keto diet can be effective for weight loss, as it can lead to a reduction in appetite and an increase in fat burning due to the body's reliance on ketones for energy. It has also been found to improve insulin sensitivity, which can be beneficial for individuals with diabetes or prediabetes. Additionally, the keto diet has shown promising results in the management of epilepsy, certain neurological conditions, and metabolic disorders." 

Cons: Not all health experts are on board with keto. "Regarding efficacy in weight loss, one review published in 2018 has concluded that high-quality studies show no difference in weight loss on a keto diet versus a low-fat diet in a calorie deficit," Moody says. "Even when weight loss is seen, the review says, it is typically not sustained."

Moody adds, "Dietitians tend to dislike this diet due to it being hard to stick to, potentially lower quality of life due to the low energy that comes with cutting carbs, and with the firm understanding that the body not only needs carbs to function optimally but the body can also achieve weight loss by still consuming them. It also promotes a way of eating that can be unhealthful in the long term." She continues, "By displacing carbs, people on the keto diet tend to eat high amounts of things like bacon, butter, and other foods that are high in saturated fat, a type of fat that greatly increases your risk for heart disease."

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Bonus Tip: "Sleep Plays a Huge Role"

Pros: Sleep in and of itself is not a diet, but it is one of the major factors that can contribute to how effective your diet is when it comes to losing weight or staying fit as you age. "You have to get sleep," Michelle Pfeiffer told The Express. "We're always looking for that magic bullet and they don't exist." And she's right—sleeping makes a difference in weight loss. "While not a diet in the traditional sense, getting an adequate amount of sleep is crucial for overall health and weight management," Sabat says. "Sufficient sleep duration, typically defined as 7 to 9 hours [a night] for adults, plays a significant role in regulating appetite hormones, metabolism, energy balance, and food choices."6254a4d1642c605c54bf1cab17d50f1e

"Sleep plays a huge role in weight gain and loss," emphasizes Amy Beney MS, RD, CDCES, with Nutrition Insights. "Studies have demonstrated that getting adequate sleep helps regulate hormones, reduce cravings, helps improve insulin sensitivity, and helps support energy levels which are needed to be productive throughout the day.  These are key components in not only helping with weight loss but also maintaining desired weight loss."

Cons: None!

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