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DJO

Dr. James Okonkwo, MD, MPH

Public Health Nutrition Editor

Physician and epidemiologist with a Master of Public Health from Harvard T.H. Chan School. Studies population-level dietary patterns and their links to chronic disease.

Nutritional EpidemiologyChronic Disease Prevention

Essays by Dr.

food-science

Korean Red Ginseng: What the Clinical Trial Evidence Actually Shows

Steaming converts Panax ginseng's chemistry into compounds the fresh root never contained, and a real (if uneven) body of randomized trials has tested what those compounds do in humans. The clinical picture is more specific, and more modest, than the marketing around it.

food-science

What the Blue Zones Got Right — and What the Data Now Suggest

The five longest-lived populations in the world share dietary features that turn out to be remarkably consistent. They also share economic, social, and demographic features that are harder to replicate — and easier to ignore.

macros

High-Protein Diets and Kidney Health: What the Evidence Actually Says

The claim that high protein intake damages healthy kidneys has persisted for decades. The clinical evidence tells a more nuanced story than either side of the debate acknowledges.

micronutrients

Vitamin D Deficiency: The Most Common Nutritional Gap in 2026

An estimated one billion people worldwide have inadequate vitamin D levels. The reasons are structural — modern lifestyles, latitude, skin pigmentation — and the solutions are simpler than the supplement industry suggests.

micronutrients

Sodium and Blood Pressure: The Relationship Is More Complex Than You Think

The advice to cut salt is universal. The evidence behind it is not. Individual genetics, potassium intake, and metabolic context all shape how sodium actually affects your blood pressure.