Although sweet potatoes may be part of the Thanksgiving tradition, be sure to add these wonderful naturally sweet vegetables to your meals throughout the year; they are some of the most nutritious vegetables around. Sweet potatoes can be found in your local markets year-round, however they are in season in November and December.
What's New and Beneficial about Sweet Potatoes
- Orange-fleshed sweet potatoes may be one of nature's unsurpassed
sources of beta-carotene. Several recent studies have shown the superior
ability of sweet potatoes to raise our blood levels of vitamin A. This
benefit may be particularly true for children. In several studies from
Africa, sweet potatoes were found to contain between 100-1,600
micrograms (RAE) of vitamin A in every 3.5 ounces-enough, on average, to
meet 35% of all vitamin A needs, and in many cases enough to meet over
90% of vitamin A needs (from this single food alone).
- Sweet potatoes are not always orange-fleshed on the inside but
can also be a spectacular purple color. Sometimes it's impossible to
tell from the skin of sweet potato just how rich in purple tones its
inside will be. That's because scientists have now identified the exact
genes in sweet potatoes (IbMYB1 and IbMYB2) that get
activated to produce the purple anthocyanin pigments responsible for the
rich purple tones of the flesh. The purple-fleshed sweet potato
anthocyanins-primarily peonidins and cyanidins-have important
antioxidant properties and anti-inflammatory properties. Particularly
when passing through our digestive tract, they may be able to lower the
potential health risk posed by heavy metals and oxygen radicals. For
more details on purple-fleshed and orange-fleshed sweet potatoes, please
see our Description section below.
- It's important to have some fat in your sweet potato-containing
meals if you want to enjoy the full beta-carotene benefits of this root
vegetable. Recent research has shown that a minimum of 3-5 grams of fat
per meal significantly increases our uptake of beta-carotene from sweet
potatoes. Of course, this minimal amount of fat can be very easy to
include. In our Healthy Mashed Sweet Potatoes recipe, for example, we
include 1 tablespoon of extra virgin olive oil, and with just this one
tablespoon, each of our 4 servings for this delicious recipe provides
3.5 grams of fat.
- Some nutritional benefits from sweet potatoes simply may not be
achievable unless you use steaming or boiling as your cooking method.
Recent studies show excellent preservation of sweet potato anthocyanins
with steaming, and several studies comparing boiling to roasting have
shown better blood sugar effects (including the achievement of a lower
glycemic index, or GI value) with boiling. The impact of steaming is
particularly interesting, since only two minutes of steaming have been
show to deactivate peroxidase enzymes that might otherwise be able to
break down anthocyanins found in the sweet potato. In fact, with these
peroxidase enzymes deactivated, natural anthocyanin extracts from sweet
potato used for food coloring may be even more stable than the synthetic
dye Red 40! This benefit isn't limited to the food's appearance since
the anthocyanins have great health benefits as antioxidants and
- Most dry beans and tubers have their own unique storage proteins. Soybeans have glycinins, potatoes have patatins, yams have dioscorins, and corn has zeins. While researchers have long been aware of sporamins-storage proteins in sweet potato -only recently has research shown some of their unique antioxidant properties. The potential health benefits of the sweet potato sporamins in helping prevent oxidative damage to our cells should not be surprising since sweet potatoes produce sporamins whenever subjected to physical damage to help promote healing.