Updated October 1, 2026. The interview was released on April 5, 2021. The MAHA Summit exchange below took place on September 29, 2026. This update connects the two events; the interview itself did not discuss the summit.
Dr. Tro Kalayjian was at the MAHA Summit on September 29 when Vice President JD Vance and Health and Human Services Secretary Robert F. Kennedy Jr. began talking about food and weight. Vance said he had called Kennedy about giving up sugar. Kennedy proposed a more extensive diet. Kennedy described it as a carnivore and fermented-food approach, Vance agreed that he had followed it for a time, and then Vance called out Dr. Sean O’Mara by name in the audience. Dr. Tro heard the exchange firsthand. Read the Summit transcript.
Watch the MAHA Summit exchange: VP Vance eating carnivore?
That moment drew a public line between Kennedy’s advice, O’Mara’s approach and Vance’s own experience. Vance has separately credited Kennedy’s dietary advice while discussing his weight loss. Reporting has described Kennedy’s connection to O’Mara and the spread of O’Mara’s eating approach among public officials. The public record does not establish that O’Mara personally treated Vance. Watch Vance’s September 3 briefing; read the original Wall Street Journal reporting, syndicated.
Dr. Tro interviewed O’Mara years before this became a Washington story. Their April 2021 Low Carb MD conversation gives O’Mara room to explain what he pays attention to when someone changes their diet.
Watch the short interview excerpt: O’Mara describes a firefighter whose visceral fat fell and muscle increased, even though the scale changed less than he expected.
What the scale can miss
In the interview, O’Mara focuses on visceral fat, the fat stored around internal organs, and describes using MRI to study body composition. Dr. Tro and O’Mara discuss how two people with similar weight can have different patterns of fat storage and metabolic risk.
Visceral fat is associated with higher cardiometabolic risk. That does not mean everyone needs an MRI, or that a scan alone can predict an individual’s future. A clinician can assess risk using a broader picture that includes waist size, blood pressure, blood sugar, lipids, medical history and, when appropriate, imaging. Read the professional position statement on visceral and ectopic fat.
For another example of what stable scale weight can miss, read Dr. Tro's Fructose Is More Than a Calorie. It examines controlled human studies of fructose, liver fat and liver insulin sensitivity, including studies in which body weight did not increase.
Where fermented foods fit
In the 2021 conversation, Dr. Tro asks O’Mara about kimchi, sauerkraut and the gut microbiome. O’Mara describes why he includes fermented foods in his dietary approach and why he prefers whole foods to heavily marketed low-carb substitutes.
That is O’Mara’s approach. It does not establish that sauerkraut caused any public official’s weight loss. A useful question is whether an eating pattern is sustainable, nutritionally adequate and appropriate for the person following it. Fermented foods may be one component, but they are not a stand-alone treatment for obesity or metabolic disease.
The point beyond the headline
The Summit exchange is a reason to revisit the interview. The lasting question is how someone can tell whether a change in diet is helping. O’Mara emphasizes body composition and food quality. Dr. Tro brings the discussion to insulin resistance, cravings, exercise and the difference between whole foods and packaged products carrying a low-carb label.
No single diet in the interview should be assumed to fit everyone. Someone with diabetes who uses glucose-lowering medication may need a medication plan when making a major dietary change. People with other medical conditions or nutritional needs should make the decision with a clinician who knows their history.
Hear the full conversation: Low Carb MD Episode 169 with Dr. Sean O’Mara. The 2021 interview provides more context than a headline or short clip can.
