Key benefits of sunflower seeds
Sunflower seeds are very high in vitamin E, which is linked to a reduced risk of heart disease. Sunflower seeds also provide antioxidant defence against cancer as well as against cataracts.
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How much sunflower seeds should you eat?
Sunflower seeds are high in calories and should therefore be eaten in limited quantities. If you eat two tablespoons of sunflower seeds a day, you will double your vitamin E intake.
Hey I had to look this up for you as my boyfriend loves sunflower seeds and this is what I found...none of the sites I visited said anything about rocks. So I would say you are fine to eat them, just in moderation!!