If you’ve heard about brazil nuts containing such high levels of selenium that it’s dangerous to consume more than 1-2 per day, and you’ve also heard that sesame seeds are a good source of selenium as well, you may be wondering if tahini is at all dangerous too.
The answer is no; the level of selenium in sesame seeds is well below any limit for danger. In fact, you could eat an entire cup of sesame seeds and still only be at 50% of the amount of selenium contained in just one brazil nut. Whereas brazil nuts contain about 95.8mcg of selenium per nut, an entire cup of sesame seeds provides only 49.5mcg. The safe upper limit for selenium consumption is thought to be at 400mg. The recommended daily intake for selenium for adults (age 14+) is 55mcg.
Tahini is ground sesame seeds (no other ingredients), so the nutritional value is similar. Even though tahini is often cooked in some way – whether the seeds be toasted or roasted – the amount of selenium in tahini tends to be approximately the same because heat does not usually destroy minerals like it does vitamins (selenium is a mineral, as is calcium and iron). However, if you prefer the raw version for flavor or vitamin content (though sesame seeds are really a mineral champion, not so much a vitamin champ), there are commercially available raw tahini products, or simply pouring some sesame seeds in a blender will give you a homemade raw tahini in just minutes.