Selenium硒

Food · soil matters

Stop 1/5

食物 · 土壤决定

Selenium is the most typical case of 'soil geochemistry determines nutrition' — the same food can differ by tens of times in selenium content across regions. RDA 55 µg/day, UL 400 µg/day.

Main sources roughly:

Brazil nuts: average 70–90 µg / nut, but with huge variation (20–250 µg / nut even within the same bag, depending on the specific tree's soil) — a rare 'one nut affects your daily Se intake' foodSeafood (tuna, shrimp, sardines, salmon): 30–90 µg / 100 g, small batch variation, a stable sourceMeat + eggs: 10–40 µg / 100 g, depending on feedGrains: heavily dependent on local soil — US Great Plains wheat 50+ µg / 100 g, parts of China < 5 µg
From Heilongjiang to Yunnan in China, there is a low-selenium soil belt. Before the 1970s, Keshan disease (endemic cardiomyopathy) was rampant; after the government fortified table salt with selenium, incidence fell more than 90% — a modern example of a single trace element shaping regional health. Other global low-selenium regions include New Zealand (volcanic soil), parts of northern Europe, sub-Saharan Africa, and the US Northeast and Northwest.

In practice: diversifying food sources across regions is safer than fixing on a single staple; 1–2 Brazil nuts per day cover the RDA at low risk, but eating 10+ per day long-term is not advised (selenosis is real); people who regularly eat seafood, eggs, and meat are almost certainly not deficient.

Read story

本站提供科普与一般性建议，不替代医师诊断或处方；有症状或正在服药请咨询合格医师。 Educational content, not medical advice — consult a clinician for diagnosis or treatment.

Back

Selenium硒

Food · soil matters

Stop 1/5

食物 · 土壤决定

Read story