Paul Saladino, a U.S.-based nutrition influencer with millions of followers, has become a leading proponent of a meat-heavy diet. According to his website, Saladino holds an M.D. and completed a residency at the University of Washington in Seattle, earning a Physician Nutrition Specialist qualification. Disillusioned with what he saw as a symptom-focused approach in Western medicine, Saladino turned to social media to promote his belief that a diet centered on meat and organ consumption could lead to a healthier life.

In 2020, he published The Carnivore Code, compiling scientific evidence to argue the health benefits of a meat-based diet. The book, accompanied by a carnivorous cookbook, became a sensation, attracting the interest of celebrities, athletes, and even political figures.

What Is the Paleo Diet?
The diet advocated by Saladino falls under the broader category of the Paleo Diet, which mimics the dietary patterns of Paleolithic humans. Proponents believe that because modern humans evolved eating this way, our genes haven't had time to adapt to agricultural and processed foods. Saladino’s version, however, is particularly extreme. For years, he consumed only organs and grass-fed beef, shunning fruits and vegetables. He claims this approach cured his asthma and eczema, promoting the idea that humans thrive by eating like our ancestors.

But can such a restrictive, celebrity-endorsed diet really make us healthier?

What Did Our Ancestors Really Eat?
The Paleo Diet models itself after the eating habits of humans from the Paleolithic era (about 2.6 million to 12,000 years ago). However, were our ancestors truly carnivorous?

Early Primates and Diet Evolution
Primates, including our early ancestors, primarily ate fruits. Hominins, our direct ancestors from 6-7 million years ago, were likely omnivorous, consuming fruits, leaves, and bark. By about 3.5 million years ago, early species like Australopithecus afarensis expanded their diet to include meat, as evidenced by animal bones bearing tool marks.

Meat and Human Evolution
Meat consumption is believed to have fueled the evolution of larger brains in humans. High-calorie foods like meat and marrow provided the energy required for brain development. Smaller digestive tracts, enabled by meat consumption, allowed more energy to be directed to brain function.

Varied Diets
Despite the advantages of meat, archaeological evidence suggests that early humans did not rely exclusively on it. Plant-based foods, including roots, tubers, and seeds, remained staples. Even among modern hunter-gatherer societies, meat is not a consistent dietary cornerstone.

Modern Paleo: A Marketing Phenomenon
The modern Paleo Diet gained popularity in the 20th century with the publication of The Stone Age Diet by Walter Voegtlin, who argued that mimicking ancestral diets could improve health. Later research, such as the Kitava Study, highlighted the health benefits of unprocessed, traditional diets.

By the 21st century, books like Loren Cordain's The Paleo Diet turned the approach into a global trend, emphasizing unprocessed meats, fish, and vegetables while limiting grains, dairy, and processed foods. Celebrities like LeBron James and Gwyneth Paltrow have tried variations of the Paleo Diet, although their experiences often sparked debates about its feasibility and health implications.

Is the Paleo Diet Healthy?
Weight Loss
Short-term studies suggest that Paleo-style diets can aid weight loss. For example, a University of Otago study found that Paleo diets led to significant weight loss within six months, thanks to higher satiety from low-carb eating. However, after 12 months, weight loss outcomes were less favorable compared to diets like the Mediterranean Diet or intermittent fasting.

Health Risks
Long-term adherence to the Paleo Diet may disrupt gut microbiota. Research from Edith Cowan University found that a meat-heavy Paleo Diet increased gut bacteria associated with higher levels of trimethylamine N-oxide (TMAO), a compound linked to heart disease.

Balance Matters
While reducing processed foods aligns with modern health recommendations, avoiding all grains, legumes, and dairy may lead to nutritional deficiencies.

Conclusion: How Should We Eat?
The Paleo Diet emphasizes unprocessed foods, which is a positive takeaway. However, no single diet is universally suitable for everyone. Rather than following extreme dietary trends, individuals should consult nutrition experts and develop personalized, balanced eating habits.

Even Saladino, a staunch advocate of the Carnivore Diet, recently reintroduced carbohydrates and dairy into his diet, acknowledging the importance of flexibility in pursuing health.

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