What Vitamin D Level Do Traditionally Living East Africans Have?
About 115 nmol/L (46 ng/mL) on average, and none of them were deficient. The Maasai averaged 119 nmol/L and the Hadzabe 109 nmol/L. About 72% were above 100 nmol/L (40 ng/mL), and the highest values, 167 and 171 nmol/L, were well below estimated toxicity levels. The researchers measured blood levels in 35 Maasai and 25 Hadzabe adults living in Tanzania, just south of the equator.
Dr. Kumar’s Take:
This study offers a rare window into what human vitamin D levels might have looked like before modern life moved people indoors. Despite living in the equatorial sun, the Maasai and Hadzabe don’t sunbathe, they seek shade. Yet their average vitamin D levels hover around 115 nmol/L (46 ng/mL), far above what’s considered “adequate” in modern guidelines. That raises the question of whether current norms describe a minimum rather than an optimum, though this study measures a concentration, it does not establish one as ideal.
Key Takeaways:
✔ Traditional Maasai and Hadzabe people have a mean vitamin D level of 115 nmol/L (46 ng/mL) despite avoiding peak sun.
✔ No participants had deficiency (<50 nmol/L or 20 ng/mL); 43% had levels over 120 nmol/L (48 ng/mL).
✔ These levels may reflect evolutionary norms. The authors add that low magnesium and vitamin K status in modern diets may matter for how the body handles calcium at higher vitamin D levels.
Actionable tip:
This is what lifelong tropical sun exposure produces, not a target the study endorses. The authors say plainly that whether 115 nmol/L is optimal under a modern Western lifestyle is uncertain and should be studied. If you and your doctor do pursue a higher level, the authors point to low vitamin K2 and magnesium status as modern imbalances that affect calcium balance, with kidney stones and soft tissue calcification as the concern.
Brief Summary:
In this 2012 study, researchers measured vitamin D levels in two traditionally living East African populations: the Maasai and the Hadzabe. Although these tribes avoid direct sunlight during the hottest parts of the day, their outdoor lifestyles result in high year-round exposure to UVB rays. The average serum 25-hydroxyvitamin D level across both groups was 115 nmol/L (46 ng/mL), comparable to levels above 100 nmol/L measured in lifeguards and Hawaiians with heavy daily sun exposure. Concentrations were not related to age, sex or BMI. The authors conclude that whether this level is optimal under a current Western lifestyle is uncertain and should be studied further.
Study Design:
This observational study measured vitamin D levels in 35 Maasai pastoralists and 25 Hadzabe hunter-gatherers, all living in Tanzania near the equator. Blood samples were analyzed using liquid chromatography-mass spectrometry for precision. Researchers also documented age, sex, height, weight, and clothing habits. The tribes’ daily routines involved spending most of their day outdoors but avoiding direct sun exposure during midday.
Results:
- Mean vitamin D level was 119 nmol/L (47.6 ng/mL) in Maasai and 109 nmol/L (43.6 ng/mL) in Hadzabe, with no deficiencies reported.
- 60% of Maasai and 40% of Hadzabe had undetectable levels of D2, the plant-derived form of vitamin D.
- No correlation was found between vitamin D levels and age, BMI, or sex.
- Over 70% of participants had levels above 100 nmol/L (40 ng/mL), and even the highest values (167 and 171 nmol/L) were well below estimated toxicity levels of 250 nmol/L and above.
Why This Matters for Modern Health
Human bodies evolved to produce vitamin D through sunlight. These traditional populations show that natural outdoor living leads to much higher vitamin D levels than typically seen in modern humans.
Related Studies and Research
Historical Aspects of Vitamin D Research and Public Health Impact: Explores how early observations shaped modern guidelines.
Frequently Asked Questions
What vitamin D level did the Maasai and Hadzabe have?
Their average was 115 nmol/L (46 ng/mL). The authors compare this with levels above 100 nmol/L measured in lifeguards working outdoors for weeks and Hawaiians getting more than 3 hours of sun a day.
Do these tribes get their vitamin D from food?
Their diets include some animal foods. The Maasai eat mainly curdled milk and meat, now with maize porridge. The Hadzabe eat fruits, tubers, honey, meat and an occasional fish. Both groups spend most of the day outdoors, and the authors describe their sun exposure habits as likely comparable to those of early humans in Africa.
Is 115 nmol/L (46 ng/mL) safe for me?
It is well below the estimated toxicity range, but this study cannot say it is right for you. Even the highest values here, 167 and 171 nmol/L, stayed well under the estimated toxicity levels of 250 nmol/L and above. The authors raise a concern that higher levels could nudge up blood calcium, and they link that risk to other modern imbalances such as low magnesium and vitamin K status.
Should I try to match these vitamin D levels?
Not necessarily. The study reports 115 nmol/L as what these populations run at, and states that whether this concentration is optimal under the conditions of the current Western lifestyle is uncertain and should be the subject of further study. That is a question for you and your doctor, not something this paper settles.
Why don’t they get vitamin D toxicity?
They do not take high-dose supplements, and even their highest values (167 and 171 nmol/L) stayed well below estimated toxicity levels of 250 nmol/L and above.
Conclusion
This study suggests the evolutionary “normal” vitamin D level might be around 115 nmol/L (46 ng/mL). The authors stop short of calling it a target, and say the question of whether it is optimal for modern life remains open. Discuss this study with your doctor, including vitamin K2 and magnesium, which the authors flag as part of healthy calcium balance.
