Ten Health Risks and Dangers Associated with Sunflower Seeds
In general, sunflower seeds are not considered as an unhealthy or harmful food. Below are some possible health risks listed:
1. Calories and Weight Gain
Sunflower seeds are high-calorie and high-fat food (1).
- One ounce (28 grams) of dry roasted sunflower seed kernels (hulled — without hulls) contains 165 Calories.
- One-half cup (64 grams) contains 372 Calories.
Sunflower seeds by themselves are not fattening, but eating them in large amounts can contribute to weight gain.
2 oz (57 g) of salted sunflower seed kernels contains about 370 mg of sodium (2), so individuals on a low-sodium diet may need to avoid them.
3. Mouth Sores, Enamel Loss
- Grinding whole sunflower seeds with the teeth can cause gum sores.
- In this Pakistani investigation, consumption of dry roasted sunflower seeds was associated with the higher rates of damage of the tooth enamel.
Shells could theoretically stick in your throat and cause inflammation of the epiglottis (the fold that covers the voice box).
Picture 1. Sunflower seed or its shell can stick behind the epiglottis
(source: Flickr, Creative Commons License)
Picture 2. Sunflower seeds can get stuck above the epiglottis
or enter the windpipe (red arrows)
(adapted from Wikimedia, CC license)
5. Aspiration During a Baseball Game
In 2010, in Northern Virginia in the United States, a baseball player was hit by a ball in the throat while chewing sunflower seeds. He aspirated on some seeds, what triggered cardiac arrest; he died later in the hospital (18).
6. Stomach Ache, Upset Stomach, Irritable Bowel Syndrome (IBS)
- Both shelled and unshelled sunflower seeds are high in soluble fiber (1,17), which can cause excessive bloating, abdominal pain and flatulence.
- Both shelled and unshelled sunflower seeds are high in insoluble fiber (1,17), which may trigger diarrhea in some individuals with diarrhea-predominant irritable bowel syndrome (D-IBS).
7. Sunflower Seed Shells, Bezoars and Constipation
Eating large amounts of sunflower seeds with shells at once may cause severe constipation (obstipation, impaction) and formation of bezoar (a clump of undigested material) in the rectum, which may need to be removed under general anesthesia (3).
Picture 3. CT image of the seed bezoar in the colon
- Sunflower seed dust may trigger an allergic reaction or anaphylactic reaction or development of chronic asthma in sensitive people who, for example, clean bird cages (4,5).
- Eating sunflower seeds, which may contain high amounts of nickel, can trigger eczema in individuals with nickel allergy (13).
- Due to mixing during manufacturing, certain sunflower seeds sold in stores may be contaminated with soy allergens.
- Individuals who are allergic to sunflower seeds only rarely react to sunflower oil (7).
- Cross-reactivity between sunflower seeds and pistachios, peanuts and walnuts (8), mustard seed (8), certain fruits (10) and ragweed pollen (11) has been reported.
Some sources (14) mention sunflower seeds as a possible migraine trigger. The supposed triggering substance is tyramine (14).
10. Manganese Overdose
Individuals with a genetic disease called “Dystonia/Parkinsonism, Hypermanganesemia, Polycythemia, and Chronic Liver Disease” should avoid sunflower seeds because they are high in manganese (15).
Oxalate Kidney Stones?
For individuals with oxalate kidney stones, doctors recommend low-oxalate diet with less than 50 milligrams oxalates per day. One-half cup of sunflower seeds may contain up to 10 milligrams oxalates (16).
Some individuals have reported getting addicted to dill-flavored sunflower seeds.
Some Chinese manufacturers add aluminum and talc powder to sunflower seeds to enhance flavor. Aluminum toxicity has not been reported, though.
Sunflower seeds can accumulate cadmium, lead, nickel, vanadium, zinc and other heavy metals but not necessary in greater amounts than certain other plants, like barley (6,21) or spinach.
Some doctors recommend avoiding eating sunflower and other seeds to individuals with intestinal diverticulosis, but the association between sunflower seeds and diverticulitis has not been proven (12).
Cancer.org does NOT mention sunflower seeds as a risk of oral cancer.
Vitamin B6 Toxicity?
According to Linus Pauling Institute, vitamin B6 toxicity caused by any food, including sunflower seeds, has not been reported so far. One cup of dehulled sunflower seeds contains about 1 mg vitamin B6, and the tolerable amount of vitamin B6 for adults is 100 mg per day and for children 4-13 years old 40-60 mg per day.
Possible Health Benefits of Sunflower Seeds
Sunflower seeds are high in:
- Monounsaturated fats
- Vitamin E
- Vitamins from B complex
In summary, unsalted, shelled sunflower seeds seem to have fewer side effects than salted whole seeds.
- USDA.gov (Sunflower seed kernels calorie and nutrient content)
- USDA.gov (Salted sunflower seeds)
- PubMed (Unshelled sunflower seeds and constipation)
- PubMed (Airborne allergy to sunflower dust)
- PubMed (Anaphylactic reaction)
- Lombi E et al, 1998, Mobility of heavy metals in soil and their uptake by sunflowers grown at different contamination levels Agronomy
- Halsey AB et al, 1986, Sunflower oil is not allergenic to sunflower seed-sensitive patients PubMed
- Aaaai.org (Nuts cross-reactivity)
- Madrid F et al, 2002, Heavy uptake by barley and sunflower grown in abandoned animal lagoon soil Pen State University
- Wiley.com (Cross-reactivity between seeds and fruits)
- Acaai.org (Ragweed seed cross-reactivity)
- Niddk.nih.gov (Diverticulosis)
- PMC (Nickel allergy)
- Mgwater.com (Sunflower seeds and migraine)
- Nih.gov/books (Dystonia/Parkinsonism, Hypermanganesemia, Polycythemia, and Chronic Liver Disease)
- How To Eat A Low Oxalate Diet The University of Chicago
- Journal of Food Composition and Analysis (2002) 15, 715-723
- Loudountimes.com (A baseball player dies from aspiration of sunflower seeds)