A single serving of fresh kale provides a good proportion of the RDI for vitamins K1 and C.
Seaweed is an excellent source of iodine, as 1 gram provides 20–1,000% of the RDI. Note that brown seaweed is much higher in iodine than other types and should not be consumed daily.
Liver contains very high amounts of vitamin B12, vitamin A, and copper. Yet, it should not be consumed more than once or twice per week.
Brazil nuts are the single best dietary source of selenium. Just one large nut contains more than the RDI.
Clams and oysters both contain high amounts of vitamin B12, which is especially important for older adults. Shellfish are also high in many other nutrients.
Sardines are a very nutrient-rich fish. Not only are they loaded with essential fatty acids, but 1 serving contains over 300% of the RDI for vitamin B12.
Yellow bell peppers are an excellent source of vitamin C. One large specimen provides almost 600% of the RDI — up to 4 times more than oranges.
Cod liver oil is an excellent source of omega-3 fatty acids, vitamin D, and vitamin A. However, taking more than 1–2 tablespoons (14–18 ml) per day is not recommended.