Dr. Dariush Mozaffarian, a prominent American cardiologist and nutrition expert, has advanced a perspective that food should be viewed as a form of medicine, emphasizing the critical role of diet quality in addressing obesity and chronic diseases. In his latest work, Mozaffarian critiques the widespread consumption of ultra-processed foods and advocates for a shift toward whole, minimally processed ingredients to improve health outcomes.

Mozaffarian explains that refined carbohydrates undergo extensive industrial processing, which strips them of their natural cellular structure and essential nutrients. This alteration compromises their nutritional value and may contribute to metabolic dysfunction. Contrary to popular belief, he suggests that humans may not be inherently predisposed to crave highly processed foods; in fact, exposure to the natural hormone GLP-1—targeted by drugs like Ozempic—can make such products taste repellent. Instead, he recommends choosing whole grains and healthy fats as dietary staples.

One notable assertion in his approach is the endorsement of a high-fat, low-carbohydrate diet, which he says can increase resting metabolic rate by roughly 300 calories per day compared to a low-fat, high-carb regimen. This challenges the simplistic view of the human metabolism as a passive “bucket” system, where calories are simply consumed and expended. Mozaffarian argues that metabolic health depends significantly on the type of food consumed, not just caloric intake.

A central focus of his analysis is the human gut microbiome, which comprises approximately 5,000 distinct bacterial species. Research indicates that Western populations may have experienced a sharp decline in bacterial diversity—up to two-thirds fewer unique species than hunter-gatherer groups—potentially contributing to increased rates of allergies, asthma, and autoimmune conditions. One example is the bacterium Bifidobacterium longum subsp. infantis, which plays a role in immune system development and is found in 90% of infants in countries like Bangladesh and the Gambia, but less than 15% of European and American newborns.

Mozaffarian offers practical dietary advice such as consuming fruit—like apples—before meals to enhance GLP-1 levels, which may help reduce total calorie consumption. He cautions against the widespread obsession with protein supplementation unless engaging in heavy resistance training, noting that many protein-branded products are ultra-processed and do not necessarily support better health.

While Mozaffarian acknowledges that diet plans like keto or paleo often result in weight loss, he attributes this effect largely to improvement over the typical highly processed American diet rather than inherent superiority. He also questions conventional nutritional labeling and the long-standing recommendation to eat a diverse array of foods, suggesting that consistent, reliable eating routines may be more effective in maintaining health in the modern environment.

The latter portion of Mozaffarian’s book delves into broader policy discussions, including taxation on unhealthy foods and prescriptions for nutritious meals, with a primary focus on the American context. Though offering thoughtful insights, some critics argue the work occasionally overstates the potential of diet to prevent or treat serious conditions such as cancer or dementia. Nonetheless, Mozaffarian’s call to reframe food as a tool for healing contributes to ongoing discussions about combating obesity and chronic disease in the United States.