Are Sunflower Seeds Healthy or Not?
Table Of Content:
- Are Sunflower Seeds Healthy or Not?
- Health Benefits
- Nutrition Facts
- Proteins for Vegetarians
- Ketosis, Low-Carb and Ketogenic Diet
- Dietary Fiber
- Vitamin E
- Potassium and Blood Pressure
- Selenium and Heart Disease
- Phytic Acid
- Sunflower Seeds and Cancer
- Frequently Asked Questions
It may be inappropriate to say that sunflower seeds are either healthy or unhealthy. They may be a good source of energy for a starving man, but can be fattening for someone who is addicted to them. Sunflower seeds are a food, not a drug, so do not expect that you will cure your skin or hair problems or fight cancer with them. They may stimulate bowel motility.
Sunflower seeds are sometimes referred as a “superfood,” because they are “packed with healthy minerals and vitamins.” The fact is that those nutrients are usually helpful only for people with nutrient deficiencies.
Picture 1. Immature sunflower seeds in the head of sunflower
Picture 2. Confectionary sunflower seed in the black shell with white stripes
(source: Flickr.com, Creative Commons Licence)
Picture 3. A raw, hulled and unhulled sunflower seed
(source: Wikipedia, Creative Commons Licence)
Picture 4. A handful of sunflower seeds (about 1 oz)
(source: Wikihow, Creative Commons License)
Dietary Guidelines for Americans 2010 written by the U.S. Department of Health and Human Services recommend including sunflower seeds and oil into a diet (20). Benefits of eating sunflower seeds may be associated with:
- Energy (calories)
- Unsaturated fats
Sunflower seeds are high in calories and are therefore a good source of energy.
TABLE 1: Calorie content of sunflower seeds (1,2)
|Sunflower seed (one serving)||Calories (kcal)||Calories (kcal) from fat|
|Dried, with hulls (in-shell) (1 cup, 46 g edible yield)||270||200|
|Raw or dry roasted, hulled (1/2 cup, 64 g)||370||270|
|Oil roasted, hulled (1/2 cup, 67 g)||400||290|
|Toasted, hulled (1/2 cup, 67 g)||415||320|
In general, you lose weight until you eat less calories than you spend them. One half of cup of oil roasted sunflower seeds contains 400 Calories, which is one fifth of the daily calorie needs for a sedentary adult man (2,500 Calories).
TABLE 2: Nutritional value of one big serving of dry roasted sunflower seed kernels (1/2 cup or 64 grams) (1,11)
|NUTRIENT||AMOUNT||DAILY VALUE (%)|
|Total FAT||32 g||49%|
|-saturated fat||3.3 g||16%|
|– omega 3||44 mg|
|– omega 6||21 g|
|Total CARBOHYDRATE||15 g||5%|
|–dietary fiber||7 g||28%|
|Vitamin E||17 mg||83%|
|Vitamin B3 (niacin)||4.5 mg||22%|
|Vitamin B6 (pyridoxine)||0.5 mg||25%|
|Pantothenic acid||4.5 mg||45%|
|Phytic acid||0.5-1 g (22)|
Oleic Acid, Linoleic Acid, Cholesterol Levels and Heart Disease
Sunflower seeds are high in oleic acid, which is monounsaturated fatty acid, and linoleic acid, which is omega-6 polyunsaturated fatty acid (see Table 2). When oleic and linoleic acid are substituted for saturated fats in the diet, they may reduce total and LDL cholesterol and the risk of coronary heart disease (3,5).
Essential Fatty Acids
Sunflower seeds are very high in linoleic acid, but low in alpha-linolenic acid (1).
Omega-6 to Omega-3 Ratio
Sunflower seeds have omega-6 to omega-3 fatty acids ratio 477 : 1. Some researchers believe that omega-6 to omega-3 ratio greater than 10 : 1 promotes inflammation in the human body (25), but others do not thinks so (26).
Proteins for Vegetarians
Sunflower seeds are a good source of proteins for vegetarians. One half of cup of dry roasted sunflower seed kernels contains about 12 grams proteins, which is 25% Daily Value (1). They also contain most of essential amino acids in the adequate amount, except of methionine and maybe lysine (1,7).
Ketosis, Low-Carb and Ketogenic Diet
Ketosis means appearance of ketones in the blood. Your body starts to produce ketones from the dietary or body fats, when you eat less than about 100 grams available carbohydrates (total carbs minus fiber) per day. Theoretically, by eating nothing but sunflower seeds for several days in a row in the amount to cover daily calorie needs for a sedentary male (2,500 Calories, that is 3.4 cups or 192 grams sunflower seed kernels), you would get about 60 grams of available carbohydrates per day what would produce moderate ketosis (1).
A strict ketogenic diet, such as Atkins diet, allows only 20 grams available carbohydrates per day, which produces considerable ketosis. One half of cup of dry roasted sunflower seed kernels contains about 8 grams available carbohydrates (1). Several books mention sunflower seeds as a part of ketogenic diet.
NOTE: Ketosis without a significant drop of the blood pH is not considered dangerous. Even strict ketogenic diet usually results only in ketosis, but not in ketoacidosis, which is a dangerous medical condition, which is usually caused by metabolic disorders, such as diabetes.
One half of cup of dry roasted sunflower seed kernels (64 grams) contains 5-7 grams of dietary fiber; from this 75% insoluble and 25% soluble fiber (1,15). Insoluble dietary fiber can stimulate bowel motility (16). On the other hand, large amount of unhulled sunflower seeds eaten at one sitting may cause severe constipation (impaction) (17).
One half cup (64 grams) of dry roasted sunflower seed kernels contains 17 mg of vitamin E, which is about 80% Daily Value (recommended intake) (1).
- Vitamin E acts as an antioxidant (13).
- Vitamin E supplements in the doses greater than 200 mg/day for several years did not reduce the incidence of heart disease, diabetes, cataract or various cancers, such as breast, lung or colon cancer (13).
- Vitamin E supplements in doses 90 mg/day for several months reduced the incidence of common cold in older individuals, but the effect of vitamin E on immunity in general is not yet clearly determined (13).
Potassium and Blood Pressure
Sunflower seeds are included into the DASH diet plan (Dietary Approaches to Stop Hypertension), introduced by the U.S. National Heart, Lung and Blood Institute (6). This diet recommends foods low in sodium and saturated fats and high in magnesium, potassium and fiber — sunflower seeds fulfil all these criteria. Starting eating more sunflower seeds without changing the whole diet will probably not help to lower blood pressure, though.
Selenium and Heart Disease
One half of cup (64 grams) of dry roasted sunflower kernels contains about 50 micrograms (mcg) selenium, which is about 70% Daily Value (recommended intake) (see Table 2).
- Selenium acts as an antioxidant (14).
- In one study lasting for 15 weeks, high-selenium diet (240 mcg/day) improved mood (“clearheadedness”) in male participants (21).
- Selenium deficiency can–because of low amounts of selenium in soil in the Keshan region of China–cause Keshan disease — a heart disease in children and young women (14). Daily intake of at least 20 micrograms selenium prevents development of Keshan disease (19). One half of cup of sunflower seeds contains about 50 micrograms selenium (1) and should, theoretically, prevent Keshan disease.
Phytosterols in sunflower seeds (0.1-0.3 grams per half of the cup) do not likely significantly lower blood cholesterol levels; about 1-2 grams phytosterols (in enriched foods, such as certain margarines) are needed for this effect (9,10,11).
Sunflower seeds are high in phytic acid (22).
- Phytic acid or Inositol Hexaphosphate (IP-6) in sunflower seed kernels binds iron, calcium and zinc and may therefore reduce their absorption (22).
- Phytic acid may act as an antioxidant and may lower blood cholesterol and triglyceride levels (22).
Sunflower seeds are a good source of zinc (see Table 2). Dietary zinc is probably beneficial only for people with zinc deficiency, which is rare in the Western world.
One half of cup (64 grams) of dry roasted sunflower seed kernels contains about 80 mg magnesium, which is about 20% Daily Value (recommended intake) (see Table 2).
- In some studies, magnesium supplements in doses about 600 mg had a moderate preventing effect on migraine attacks in adults. There is lack of evidence about migraine-preventing effect of sunflower seeds, though.
- There is no firm proof that magnesium from dietary sources, including sunflower seeds, can decrease the risk of high blood pressure, heart disease, migraine, asthma or diabetes (8).
Sunflower seeds are a good source of manganese. Individuals with a genetic disease “Dystonia/Parkinsonism, Hypermanganesemia, Polycythemia, and Chronic Liver Disease” should avoid sunflower seeds and other high-manganese foods (24).
Sunflower Seeds and Cancer
There is insufficient evidence about cancer-preventing effect of sunflower seeds. In various studies, supplemental doses–even 10 times as high as found in sunflower seeds–of selenium (14), vitamin E (13) and phytic acid (23) did not reduce the risk of lung, breast, colon or prostate cancer.
Frequently Asked Questions
Can you eat the sunflower seed shells?
The shells of roasted sunflower seeds are crunchy and therefore easy to grind and swallow. Raw shells are much harder to grind. NOTE: Eating large amounts of unshelled seeds can cause severe constipation.
Are black oil sunflower seeds edible?
Sunflower seeds with completely black shells (black oil sunflower seeds) are mainly used to produce sunflower oil and to feed birds. These seeds are edible for humans but are more bitter.
Picture 5. Black oil sunflower seeds with black shells without white stripes
Are sunflower seeds good for the skin and nails?
- Sunflower seeds are high in omega-6 fatty acids, which improve the barrier function of the skin (33).
- Sunflower seeds are high in manganese, which is necessary for the healthy skin and nails (34).
- There is lack of evidence that sunflower seeds or any other food would affect acne (27).
- Zinc deficiency results in poor nail growth (41). Eating sunflower seeds helps to prevent zinc deficiency (1). In individuals who have normal blood zinc levels, eating sunflower seeds would probably not add much to the nail health.
Are sunflower seeds good for the thyroid?
Sunflower seeds are high in selenium (1). Selenium deficiency can cause hypothyroidism (28), which can be treated with selenium supplements (29) so, theoretically, eating sunflower seeds could help prevent hypothyroidism in individuals with low blood selenium levels.
Is it safe to eat sunflower seeds during pregnancy?
In general, there is probably no reason why pregnant women should not eat sunflower seeds. During pregnancy, chose unsalted (to avoid water retention) and hulled seeds (to avoid constipation). Sunflower seeds are a good source of folate (about 150 mcg per half of cup). Doctors recommend eating folate-fortified foods and folate supplements (400 mcg/day) three month before and at least for the first three months of pregnancy to prevent neural tube defects in the baby (30).
Are sunflower seeds good for diabetics?
- Several medical websites mention sunflower seeds as appropriate snacks for diabetics (36,37).
- There is lack of evidence that high vitamin E intake from supplements or foods, such as sunflower seeds would decrease the risk of diabetes 1 or 2 (13).
Can eating sunflower seeds improve memory or prevent Alzheimer’s disease?
Sunflower seeds are high in vitamin E and zinc (1), but there is insufficient evidence about preventative effect of vitamin E or zinc on Alzheimer’s disease and other types of dementia (13,35).
Are sunflower seeds good for the eyes?
There is lack of evidence that vitamin E or zinc supplements (or sunflower seeds, which are high in vitamin E and zinc) help to prevent cataract or age-related macular degeneration of the retina (AMD) (13,31,35,38).
Do sunflower seeds promote hair growth?
There is no evidence that low blood zinc levels promote hair loss or that high zinc intake, such as from sunflower seeds, would promote hair growth (32,35).
Are sunflower seeds appropriate snack for kids?
In small children, there is a risk of choking on sunflower seeds (39). There were several reports about severe constipation from sunflower seed shells (40).
Are sunflower seeds good for the liver?
In some Chinese studies in the undernourished populations, selenium supplements in doses around 200 mcg/day for several years decreased the occurrence of hepatitis B and liver cancer (14). Maybe, eating substantial amount of sunflower seeds (one half of cup contains about 50 mcg selenium) could help the same way, but there is lack of studies about this.
Can sunflower seeds help in building muscles?
In general, in athletes with regular diet and normal blood vitamin and mineral levels, adding minerals and vitamins in supplemental doses, which are much greater than those found in sunflower seeds, does not improve physical performance (42).
- In one study, adding 400 mg vitamin E to the diet for weeks did not increase physical performance in swimmers (42). One half of cup of sunflower seeds contain 17 mg of vitamin E (1).
- In one study, untrained individuals who consumed about 500 mg magnesium per day gained about 20% more muscle strength in average than those who consumed about 250 mg magnesium per day during a 7-week training period (42). One cup of shelled sunflower seeds contains about 160 mg magnesium (1).
Are sunflower seeds gluten-free?
Yes, but they can get contaminated by trace amounts of gluten when farmers use the same equipment for harvesting and storing sunflower seeds and wheat and other gluten-containing cereals. The small amount of gluten might trigger problems in very gluten-sensitive individuals.
Can sunflower seeds help to quit smoking?
Some people who quit smoking said that munching sunflower seeds helped them to keep their mouth and hands busy and distract them from smoking.