Tactical Performance Nutrition

Podcast with Diana (Harbourt) Nguyen

Today I sat down with Diana (Harbourt) Nguyen, a Performance Dietitian with 18 years of experience across D1 collegiate programs, professional athletes, and tactical athletes. She is passionate about blending performance and functional nutrition to give patients a realistic plan to optimize progress toward their goals. In a world that is full of nutrition noise, Diana’s approach cuts through the confusion to provide evidence-based, tailored guidance to everyone she works with.

Diana entered sports nutrition when the field barely existed, back when a handful of dietitians nationwide worked in athletics departments and figured it out as they went. Twelve years in collegiate sport at Texas A&M and NC State led her into the tactical world at Fort Bragg and SOCOM, where she learned quickly that the gap between sport and tactical is far wider than most practitioners assume. Diana now co-founds Allo Performance, a virtual clinic built for what she calls extremophiles, and serves as CEO of Tier 1 Nutrition. In this conversation, she breaks down how she assesses the whole person, why simplicity is the only thing that survives contact with real adherence, and how to ask the questions that actually get you the truth.

Key Quote

"Because now you're taking the athlete and then adding in the human. That's the definition of performance nutrition. It's helping the human perform in whatever facet that may be." -Diana (Harbourt) Nguyen

5 Core Themes

1. Stress is stress, and physiology does not care about your job title.
Diana works with service members, executives, elite athletes and stay-at-home parents, and her assessment barely changes. The stress load presents differently on the outside. Underneath it, the same sleep disruption, body composition struggles, hormone dysregulation and gut dysfunction keep showing up.

2. The assessment starts with the human, not the clinical data.
Her intake goes back to birth. How you were delivered, childhood ear infections, childhood abuse, early disordered eating. Not because it is interesting, but because each of those things still shapes the adult sitting in front of her. She also explains why she is asking, because prying and assessing look identical if you skip that step.

3. Simple is not a lower standard. It is the standard.
Diana has watched enough athletes over roughly eighteen years to know the ceiling: past five supplements, compliance collapses. She would rather give someone the fourth-best intervention they will actually do than the best one they will abandon by week two. That includes matching the delivery form to the person, so if they hate swallowing pills, that is her problem to solve, not theirs to overcome.

4. Multidisciplinary and interdisciplinary are not the same thing.
Having a dietitian, an MD and a PA on the same roster means nothing if they are not actually aligned. Diana's standard is that each practitioner understands the others' practice style well enough to echo the message. The moment the patient hears two conflicting recommendations, trust is gone, and everything downstream of trust goes with it.

5. AI raises the value of the practitioner rather than replacing it.
Diana welcomes patients bringing her their ChatGPT plans. She uses AI in her own business. But she draws a firm line: it can get you a partial answer, it cannot run an assessment, and it cannot adapt to the human in front of it. Her position is that the plateau is where the practitioner becomes essential.

Main Take-Home Message

Precision and simplicity are not opposites. Diana holds both by doing the complex work on her side of the table and handing the client something they can actually execute. She digs into biomarkers, gut function, exposure history and childhood, then delivers an intervention short enough to survive a real week. The skill that makes it all work isn't clinical knowledge. It is the ability to ask the right question, pause long enough to let the answer come, and understand the person well enough to know which lever will move first.

Find Diana

Website -www.alloperfomance.com

Instagram - @dianasportsrd

LinkedIn -https://www.LinkedIn.com/in/dianasportsrd/

Find the Podcast

Listen on Spotify

Listen on Apple

Watch on YouTube

Keep Raising the Bar,

Paul Oneid MS, MS, CSCS