A diet championed by Health and Human Services Secretary Robert F. Kennedy Jr. has attracted a growing group of followers within Republican circles, from Vice President JD Vance to Cabinet secretaries and former House Speaker Kevin McCarthy.

The eating plan, dubbed the "living diet" by its creator, Dr. Sean O'Mara, emphasizes grass-fed meat and fermented foods such as sauerkraut and kimchi while eliminating sugar, alcohol and heavily processed foods.

O'Mara argues the regimen can reduce visceral fat, improve gut health and boost overall well-being.

Newsweek has reached out to O'Mara via email for comment.

Kennedy has become one of its most public advocates and has encouraged several political allies to try it. Some have followed his suggestion; others have publicly ridiculed it.

While the diet has generated headlines, publicly documented results vary widely.

In some cases, officials have spoken openly about seeing improvements. In others, there’s little evidence beyond comments from colleagues or Kennedy himself.

JD Vance

Vice President JD Vance is perhaps the highest-profile follower of the diet after Kennedy.

Speaking at a Michigan event earlier this year, Kennedy cited Vance as proof that the program was working, saying: "JD Vance is also on the diet and you can see how different he looks," according to reporting by the Washington Post.

The Washington Post also reported that Vance initially adopted the diet during Lent before continuing with it afterward. His daily meals reportedly include fermented foods such as sauerkraut alongside eggs, berries and grass-fed meat.

However, despite repeated references to his appearance, there doesn’t appear to be a public statement from Vance or anyone around him, specifying how much weight he’s lost on the regimen.

Howard Lutnick

Commerce Secretary Howard Lutnick has also reportedly joined the growing group of officials following O'Mara's nutrition advice.

According to the Wall Street Journal (WSJ), referencing discussions among administration officials, Lutnick adopted the program after conversations involving Kennedy and O'Mara.

Despite steering clear of red meat for years, Lutnick has embraced the diet, and even replaced Diet Coke with plain iced coffee, the WSJ says.

While Lutnick's participation has been widely reported, there’s little publicly available information about how much weight, if any, he’s lost while following the plan.

Sean Duffy

Transportation Secretary Sean Duffy is another Cabinet member linked to the diet.

One of the most notable public comments about Duffy's results came indirectly. Former House Speaker Kevin McCarthy reportedly noticed a change in Duffy's appearance and remarked that his skin looked "glowing."

Although Duffy has been cited as a participant in the diet, publicly available reporting doesn’t include any weight loss details or results.

Kevin McCarthy

McCarthy himself, although not a member of the administration, has emerged as one of the most notable Republican converts.

According to reports, McCarthy decided to try the program after noticing changes in Sean Duffy's appearance and asking about his routine. After meeting with O'Mara, McCarthy reportedly began following the plan himself.

McCarthy has claimed the most concrete result outside of Kennedy's own testimony, saying he lost approximately four inches from his waist while following the program.

RFK Jr.

Obviously, Kennedy remains the clearest example of someone publicly crediting the diet with significant results.

The Health Secretary has repeatedly said he lost 20 pounds in 30 days after adopting O'Mara's approach. In separate interviews and public appearances, Kennedy has also claimed the diet improved his mental clarity, reduced chronic aches and pains, and alleviated symptoms associated with atrial fibrillation.

What The Experts Say

While supporters point to weight loss and improved well-being, some health experts have expressed caution about any broad claims surrounding the diet. For example, researchers from the journal Nutrients concluded that support for the carnivore diet remains limited and noted that diets high in red and processed meat have been associated in broader studies with elevated risks of cardiovascular disease, certain cancers, and reduced life expectancy.

The regimen combines elements of a carnivore diet with fermented foods, and nutrition specialists note that individual results can vary significantly based on factors including calorie intake, overall health, and lifestyle habits.

Newsweek has contacted Dr. Kevin Hall, Senior Investigator for the National Institutes of Health, via email for comment.

For now, the clearest publicly reported results are Kennedy’s claim of losing 20 pounds in 30 days and McCarthy’s reported claim of losing approximately four inches from his waist. Neither outcome has been independently verified.

Contact Newsweek editors on this story: Tobias Meyjes and Cristina Diciu.