Why a Single Brazil Nut Provides More Selenium Than Any Other Food
Brazil nuts (FDC 170569) contain 1917mcg selenium per 100g — 3,485% of the 55mcg daily value. This is not a typo: brazil nuts contain more selenium per gram than any other food by orders of magnitude. The next highest common food is yellowfin tuna at 90.6mcg per 100g — brazil nuts have 21 times more [1].
A single brazil nut (~5g) provides approximately 96mcg selenium — 174% of the daily value in one nut. Two nuts provide ~192mcg (349% DV), and three nuts provide ~288mcg (524% DV). The tolerable upper intake level for selenium is 400mcg/day — meaning just 4 brazil nuts approach that limit [1].
Selenium content varies significantly by growing region — nuts from the Pará region of Brazil tend to be highest. The USDA figure of 1917mcg/100g represents a specific measured sample; individual nuts can range from ~5mcg to ~500mcg each depending on soil selenium concentration where the tree grew [2].
Why Brazil Nuts Are Best Tracked by Count, Not by the Handful
Each brazil nut (~5g) has approximately 33 kcal, 3.4g fat, 0.7g protein, and 0.6g carbs. Three nuts (15g): 99 kcal, 10.1g fat, 2.1g protein. One ounce (28g, about 5-6 nuts): 185 kcal, 18.8g fat, 4.0g protein [1].
The calorie density is 659 kcal per 100g — among the highest of any nut, comparable to macadamia (718 kcal) and pecans (691 kcal). Because brazil nuts are large (~5g each vs. almonds at ~1.2g each), "a handful" of brazil nuts can easily reach 300+ kcal (9-10 nuts) while the same volume of almonds might be 160 kcal [1].
For logging purposes, counting nuts is far more accurate than estimating weight. The per-nut math is simple: multiply the nut count by 33 for approximate calories. Five nuts = 165 kcal. Ten nuts = 330 kcal. This per-unit tracking approach is more practical than weighing for a food eaten in such small quantities [1].
The Mineral Density Behind the Selenium Headline
Brazil nuts' selenium dominates the conversation, but the broader mineral profile is substantial: magnesium: 376mg per 100g (90% DV) — comparable to almonds (270mg) and approaching cashews (292mg). Six nuts (28g) provide 105mg magnesium (25% DV) [1].
Phosphorus: 725mg per 100g (58% DV) — among the highest in tree nuts. Calcium: 160mg per 100g (12% DV) — more than most nuts except almonds (269mg). Copper: 1.74mg per 100g (194% DV) — nearly double the daily value, making brazil nuts one of the richest copper sources [1].
Iron: 2.43mg per 100g (14% DV), zinc: 4.06mg per 100g (37% DV), and potassium: 659mg per 100g (14% DV) round out the mineral spectrum. A 6-nut serving covers meaningful percentages of 8 different mineral daily values — selenium, copper, magnesium, phosphorus, manganese, zinc, iron, and calcium [1].
67.1g Fat With 24g Polyunsaturated: How Brazil Nuts' Fat
Brazil nuts are 67.1% fat by weight — broken down as: 16.1g saturated (24%), 23.9g monounsaturated (36%), and 24.4g polyunsaturated (36%). The remaining 4% is other fatty acid types. This is a more balanced saturated-to-unsaturated ratio than coconut (82% saturated) but higher in saturated fat than walnuts (9%) or almonds (8%) [1].
The polyunsaturated content (24.4g per 100g) includes approximately 20mg omega-3 (ALA) per 100g — a trace amount compared to walnuts (9.1g) or flax (22.8g). The dominant fatty acid is linoleic acid (omega-6). Brazil nuts are not a meaningful omega-3 source [1].
Vitamin E: 5.65mg per 100g (38% DV) — a fat-soluble antioxidant that is abundant in high-fat nuts. Six nuts provide 1.6mg vitamin E (11% DV). Thiamine: 0.617mg per 100g (51% DV) — unusually high for a nut. These two micronutrients plus the extreme selenium make brazil nuts a concentrated source of three specific nutrients [1].
The Tolerable Upper Limit Question: Why 1-3 Brazil Nuts per Day
The selenium tolerable upper intake level (UL) is 400mcg/day for adults. At ~96mcg per nut (using the USDA average), 4 brazil nuts per day approach this limit (384mcg). Five nuts could exceed it. This makes brazil nuts the only common food where overconsumption of a single micronutrient is a realistic tracking concern [2].
Many nutrition-aware individuals adopt a 1-3 nuts per day pattern: 1 nut = 96mcg selenium (174% DV), 2 nuts = 192mcg (349% DV), 3 nuts = 288mcg (524% DV). Even at 3 nuts daily, total selenium from all dietary sources should be considered since other foods (tuna, eggs, chicken) also contribute [3].
The practical takeaway for logging: track brazil nuts individually and daily. Unlike almonds or cashews where a 1-oz serving is standard, brazil nuts are most accurately and safely tracked as 1-3 individual nuts. At 33 kcal per nut, the calorie impact is minimal — it's the selenium that drives the portion limit [2].
Brazil Nuts vs. Other Tree Nuts (per 100g)
| Nutrient | Brazil Nuts | Walnuts | Almonds | Cashews | Macadamias |
|---|---|---|---|---|---|
| Calories (kcal) | 659 | 654 | 579 | 553 | 718 |
| Protein (g) | 14.3 | 15.2 | 21.2 | 18.2 | 7.9 |
| Selenium (mcg) | 1917 | 4.9 | 4.1 | 19.9 | 3.6 |
| Magnesium (mg) | 376 | 158 | 270 | 292 | 130 |
| Vitamin E (mg) | 5.65 | 0.7 | 25.6 | 0.9 | 0.54 |
| Fiber (g) | 7.5 | 6.7 | 12.5 | 3.3 | 8.6 |
Practical Tips for Brazil Nuts
- 1
A single brazil nut (~5g) provides 96mcg selenium — 174% DV — more selenium than any other food in any serving size [1].
- 2
Track by nut count: 1 nut ≈ 33 kcal. Five nuts = 165 kcal. This is the simplest calorie tracking for brazil nuts [1].
- 3
1-3 nuts per day is the range most nutrition trackers use — the selenium UL is 400mcg/day, and 4 nuts approach that limit [2].
- 4
376mg magnesium per 100g (90% DV) — brazil nuts are also a top-tier magnesium source, often overshadowed by the selenium content [1].
- 5
Selenium content varies by origin — nuts from selenium-rich soils (like Pará, Brazil) can have 5-10x more selenium than those from depleted soils [2].
Frequently Asked Questions — Brazil Nuts
How many calories are in a brazil nut?
How much selenium is in one brazil nut?
How many brazil nuts should I eat per day?
Can you eat too many brazil nuts?
Are brazil nuts high in fat?
Do brazil nuts have magnesium?
Important Notice
Nutritional values are based on USDA FoodData Central data for nuts, brazilnuts, dried, unblanched (FDC 170569). Selenium content varies significantly by growing region — the USDA value of 1917mcg/100g represents a specific sample. Individual nuts can range from ~5mcg to ~500mcg selenium each. Roasted, blanched, and nut butter values are estimated from similar products and manufacturer data. This tool is for informational and nutrition journaling purposes only — it is not a substitute for guidance from a qualified nutrition professional.
About the Author
Certified fitness professional and nutrition researcher with over 10 years of experience in the fitness and wellness industry. Founder of Food Nutrify, dedicated to making accurate, science-backed nutrition data accessible to everyone through free, easy-to-use calculators.
References & Sources
- [1] USDA FoodData Central (2024). Nuts, brazilnuts, dried, unblanched (FDC 170569). U.S. Department of Agriculture, Agricultural Research Service.
- [2] Cardoso, B. R. et al. (2017). Brazil nuts: Nutritional composition, health benefits and safety aspects. PubMed — Food Research International.
- [3] Martens, I. B. G. et al. (2022). Brazil nut intake as a strategy to improve selenium status and associated outcomes. PMC — Nutrients.