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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.

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.