Why can’t we eat sunflower seeds whole? Great question. I know about this one firsthand since I became hooked on sunflower seeds (and their hulls, as the shells are technically called), back in the summer after fourth grade. My summer camp took a field trip to a minor league baseball game, and as a special treat, gave out sunflower seeds to all of us to eat at the game. I thought chewing and spitting out the sunflower seed was so gross that I decided to eat the sunflower seed whole — kernel, hull, everything. Besides, the outside is the part that’s salted and tastes the best to a kid like me anyway. Great idea, right?
Before I tell you what happened to me the weekend following the sunflower seed incident, let’s talk a little about these nifty little creations. Sunflower seeds are the fruit from — surprise! — sunflowers. The outside shell of the sunflower seed is actually referred to as the hull. When the hull is left intact, the seeds are called in-shell sunflower seeds. When the hull is removed, the seeds themselves are called kernels. The former is usually found in the grocery aisle next to the nuts, while the latter is usually found next to the other seeds used as spices or toppings, such as poppy seeds or sesame seeds.
Eating sunflower seeds has long been an American pastime, particularly at baseball games. As anyone who has been to a baseball game can tell you, the floor of the bleachers is usually littered (and in some stadiums, covered) with the hulls of sunflower seeds.
So why can’t we eat the shell? The truth is, like many things in nature around us, you can eat it, but you may not like the results. The result of my trying to eat the shells of the sunflower seeds at the ball game that fateful summer? A weekend at home in discomfort. Though I was fortunate to experience only mild stomach pain, eating lots of sunflower seed shells has been known to cause constipation that can result in painful blockage. Additionally, the sharp edges of the shells can cause tears in your esophagus or elsewhere along your digestive tract. Another reason to spit the shells instead of eating them.
Why do sunflower seeds have shells in the first place, you may ask? I’ve heard that the sunflower seed shells are there for the same reason that nuts have hard shells too; the shells protect the fruit inside once the nut or seed has fallen from the plant. The nut allows the seed to stay intact long enough to germinate and produce another nut tree or seed plant.
Though you may not be able to eat the hull of a sunflower seed, the kernel itself packs a nutritious punch, providing you with valuable nutrients like vitamin E and magnesium. Bonus: Sunflower seeds are rich in phytosterols, a plant chemical that has been shown to help reduce cholesterol. Sunflower seeds also contain vitamin C, iron, and even fiber, among many other nutrients.
The lesson, folks? Snack on sunflower kernels often — and stay away from the hulls.
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