February 2022 Issue
Nuts + Seeds: Sunflower Seeds
By Densie Webb, PhD, RD
Today’s Dietitian
Vol. 24, No. 2, P. 10
Shining a Spotlight on the Wholesome Seeds of Cheerful Flowers
Many of your clients and their children may buy sunflower seeds by the single-serve bagful to consume as a snack. After all, they’re sold shelled or unshelled, and they’re crunchy and come in all sorts of flavors, making them pleasing to the palate. And while they may eat them often, they may not think about where the seeds come from—that they originate from the voluminous sunflower plant.
The common sunflower (Helianthus annuus L.) is grown commercially worldwide, but it’s one of the few crops that originated in North America. A species of the Asteraceae family, its scientific name is derived from the Greek helios (sun) and anthos (flower), and the Latin annuus (annual). Sunflowers can grow to be 12 feet tall, with a flower head as large as 12 inches in diameter. Their unique size and appearance have made them common subjects for artists, including Van Gogh and Picasso. True to their name, young sunflowers follow the sun, east to west, and return at night to face east, ready for the morning sun.
Sunflower seeds are cultivated and consumed globally. While the sunflower is the national flower of Ukraine, which produces roughly one-quarter of the world’s sunflowers, the United States is among the top 10 global sunflower producers. North Dakota, South Dakota, and Minnesota are responsible for 85% of North American sunflower seed production. Approximately 25% of all sunflower seed production is used to produce birdseed.1
Both sunflower seeds and sprouts contain highly nutritious components including fiber, protein, unsaturated fats, selenium, copper, zinc, iron, and vitamin E, as well as several antioxidant, antimicrobial, anti-inflammatory, and antihypertensive compounds, minerals, and vitamins that play vital roles in the prevention or treatment of diseases, including diabetes and CVD. The seeds’ possible antidiabetes properties are due to the presence of chlorogenic acid, quinic acid, caffeic acid, glycosides, and phytosterols. The seeds are also rich in protein, providing about 20% by weight.2,3
Processing
Typically, sunflower seeds are processed by drying, cleaning, grading, and roasting, and flavorings/seasonings sometimes are added.
After harvesting, sunflower seeds are rapidly dried. Dirt and debris are removed from the dried seeds, after which the seeds are graded by size. The largest seeds are processed as a snack food. The medium-sized seeds are used as ingredients for packaged foods such as cookies, salads, or ice creams. Finally, the smallest seeds are used for bird or pet food.1
Added flavorings can range from taco and bacon to pickle and ranch. While unsalted sunflower seeds are virtually sodium-free, flavored sunflower seeds often are high in sodium. The sodium in 1 1/4 cups of in-shell sunflower seeds can be close to 2,200 mg. The 2020–2025 Dietary Guidelines for Americans and the American Heart Association recommend a limit of 2,300 mg of sodium for an entire day.
Sunflower seeds can be purchased either in-shell or as kernels. According to the National Sunflower Association, in-shell means the seed is left intact with the “meat” of the seed in the shell. Sunflower seed kernels have had the hull mechanically removed and can be eaten “as is.” Several companies offer organic sunflower seeds.
Culinary Uses
Sunflower oil can be extracted from sunflower seeds. It’s cold pressed and requires minimal processing to produce a light oil that can be used for some cooking applications. Typically, sunflower seed oil is more expensive than oils derived from soybeans or corn.
Sunflower oil is available in refined (neutral-tasting) and cold-pressed (buttery, nutty) forms, and these variations are equally common in the United States. Cold-pressed sunflower oil has a low smoke point and is best used in vinaigrettes and other low-heat applications. Refined sunflower oil, on the other hand, has a high smoke point (440˚ to 475˚ F), which makes it good for frying and sautéeing.4
Aside from eating them as a snack, the hulled kernels can be incorporated into a wide range of dishes.
The following are just a few possible suggestions for clients:
• Sprinkle kernels on top of a salad.
• Add them to packaged trail mix if they’re not already included.
• Stir them into oatmeal, as one would pecans or walnuts.
• Sprinkle them over stir-fry dishes.
• Add them to veggie burgers.
• Mix them into bread and muffin batters.
• Use sunflower butter in place of peanut butter.
• Add them to vegetable casseroles.
• Use ground sunflower seeds as breading for chicken or fish.
• Add them to tacos.
• Use them in pesto in place of pine nuts.
• Blend them into ground meat for burgers.
Click to enlargeNutrition and Health
According to Cordialis Msora-Kasago, MA, RD, a national spokesperson for the Academy of Nutrition and Dietetics (the Academy), “sunflower seeds and byproducts have been used in ethnomedicine for generations to treat conditions such as hypertension and diabetes, but there’s a paucity of research validating these uses.”
However, some animal and human studies have shown that the compounds found in sunflower seeds have antidiabetes properties. Sunflower seeds are rich in chlorogenic acid and caffeic acid, making up 70% of the total polyphenols. Both compounds are known to reduce blood glucose levels; a 2016 study investigated the effects of daily consumption of 1 oz of sunflower seeds on blood sugar and blood cholesterol levels in a small group of patients with type 2 diabetes. The researchers found that regular consumption of sunflower seeds improved blood sugar and raised HDL cholesterol.5
According to the National Sunflower Association, sunflower oil is the highest in vitamin E among the leading oils, providing 45 mg/100 g of oil. While all sunflower oil is low in saturated fat, there are three sunflower oil fat profiles—linoleic sunflower oil, high in polyunsaturated fat; high-oleic sunflower oil, high in monounsaturated fat; and a newer variety called NuSun, which has about 65% monounsaturated fat and 26% polyunsaturated fat.
A small, double-blinded, randomized crossover study of 31 men and women aged 25 to 64 compared the effects of consuming a diet rich in NuSun sunflower oil vs an average American diet and a diet rich in olive oil. The researchers found that total cholesterol decreased by 4.7% and LDL cholesterol decreased by 5.9% on the NuSun sunflower oil diet compared with the average American diet. There was no difference in cholesterol levels between the average American diet and the olive oil diet.6
In addition to being high in oleic acid, sunflower seeds are significantly higher in vitamin E compared with sesame seeds, poppy seeds, and pumpkin seeds. In fact, sunflower seeds are one of the highest natural sources of vitamin E in the food supply.7
Melissa Prest, DCN, RDN, CSR, LDN, foundation dietitian for the National Kidney Foundation of Illinois and a national spokesperson for the Academy, says that sunflower seeds are a great protein option for vegetarians. “An ounce of sunflower seeds provides more than twice the protein of black beans or tofu.”
Sensitivity
While sunflower seeds are rich in nutrients and several health-promoting compounds, they can in rare instances trigger an allergic response, resulting in dermatitis in sensitive individuals and, in rare cases, anaphylactic reactions. The first case of sunflower seed allergy was described in 1979.8 The allergic response is mainly due to allergenic sesquiterpene lactones present in the seeds.8,9 Symptoms can include bronchial asthma, allergic rhinitis, conjunctivitis, angioedema (swelling under the skin), contact dermatitis, and hives. Interestingly, bird breeders are especially predisposed to sunflower allergy. Allergic reactions also can occur after eating whole grain breads that contain sunflower seeds, as the allergens in sunflower seeds are highly heat resistant and don’t break down during baking.8
A small, unpublished study presented at the 2021 American Academy of Allergy, Asthma & Immunology Annual Meeting found that, of 28 patients who had a clinical allergy to sunflower seeds, most also had a history of atopic disease and reactions to nuts.10 Still, sunflower seeds generally are less allergenic than peanuts, and sunflower seed butter often is used as an alternative to peanut butter.
Bottom Line
Sunflower seeds are nutrient-rich snacks that can be incorporated into almost any healthful diet. However, Msora-Kasago cautions that sunflower seeds are high in calories. “It’s easy to go overboard, so encourage clients/patients to include them in small portions and as part of an overall healthful diet.” While sensitivity and allergic reactions to sunflower seeds aren’t common, it’s important to ask clients about other nut and seed allergies before recommending they add sunflower seeds to their diet.
— Densie Webb, PhD, RD, is a freelance writer, editor, and industry consultant based in Austin, Texas.
References
1. Davis C. Sunflower seeds and oil. Colorado Integrated Food Safety Center of Excellence website. https://fsi.colostate.edu/sunflower-seeds-draft/. Accessed November 13, 2021.
2. Rehman A, Saeed A, Kanwal R, Ahmad S, Changazi SH. Therapeutic effect of sunflower seeds and flax seeds on diabetes. Cureus. 2021;13(8):e17256.
3. Guo S, Ge Y, Na Jom K. A review of phytochemistry, metabolite changes, and medicinal uses of the common sunflower seed and sprouts (Helianthus annuus L.). Chem Cent J. 2017;11(1):95.
4. What is sunflower oil? A guide to cooking with sunflower oil. https://www.masterclass.com/articles/what-is-sunflower-oil-a-guide-to-cooking-with-sunflower-oil. Updated August 4, 2021. Accessed November 13, 2021.
5. Cheenam B, Leena P. Effects of sunflower seeds on fasting blood glucose in diabetes mellitus type 2 patients. J Chem Pharma Res. 2016;8(4):1211-1217.
6. Binkoski AE, Kris-Etherton PM, Wilson TA, Mountain ML, Nicolosi RJ. Balance of unsaturated fatty acids is important to cholesterol-lowering diet: comparison of mid-oleic sunflower oil and olive oil on cardiovascular disease risk factors. J Am Diet Assoc. 2005;105(7):1080-1086.
7. Thomas RG, Gebhardt SE. Nuts and seeds as sources of alpha and gamma tocopherols. https://www.ars.usda.gov/arsuserfiles/80400525/articles/aicr06_nutseed.pdf. Accessed November 14, 2021.
8. Ukleja-Sokołowska N, Gawrońska-Ukleja E, Żbikowska-Gotz M, Bartuzi Z, Sokołowski Ł. Sunflower seed allergy. Int J Immunopathol Pharmacol. 2016;29(3):498-503.
9. Paulsen E, El-Houri RB, Andersen KE, Christensen LP. Sunflower seeds as eliciting agents of Compositae dermatitis. Contact Dermatitis. 2015;72(3):172-177.
10. New study examines allergic reactions to sunflower seeds. American Academy of Allergy, Asthma & Immunology website. https://www.aaaai.org/About/News/News/sunflowerseed. Published February 1, 2021. Accessed November 11, 2021.