Sweet potatoes are not only delicious, they are one of the best foods on the planet. Lately they got a lot of coverage especially after a bunch of Hollywood stars have confessed to be heavy consumers of this food.
For instance Glee’s star Matthew Morrison claims, in England’s Mirror newspaper, that he accentuated his six-pack abs for a Details magazine photo shoot with a strange diet trick: for three days, he ate only sweet potatoes. “I had to have a six-pack on the show,” he said. “The potato acts as a sponge and your body literally shrinks and gets ripped and tight.”
Also, singer Usher, confessed that in order to get a six pack, he will throw in his diet a limited amount of carbs only in the form of sweet potatoes.
Are you curious now? Let’s dig a little bit more into sweet potato and discover what’s the magic about it!
What are sweet potatoes?
The sweet potato is long and tapered tuberous root, with a smooth skin whose colour ranges between red, purple, brown and white. Its flesh ranges from white through yellow, orange, and purple.
Besides simple starches, sweet potatoes are rich in complex carbohydrates, dietary fiber, beta carotene (a vitamin A equivalent nutrient), vitamin C, and vitamin B6.
The Center for Science in the Public Interest compared the nutritional value of sweet potatoes to other vegetables. Considering fibre content, complex carbohydrates, protein, vitamins A and C, iron, and calcium, the sweet potato ranked highest in nutritional value. According to these criteria, sweet potatoes earned 184 points, 100 points over the next on the list, the common potato.
Sweet potato varieties with dark orange flesh have more beta carotene than those with light colored flesh.
Despite the name "sweet", it may be a beneficial food for diabetics, as preliminary studies on animals have revealed that it helps to stabilize blood sugar levels and to lower insulin resistance.
One medium sweet potato scores just 103 calories, 4 grams of dietary fiber and, listen to this, the 438% of the daily recommended intake of Vitamin A: impressive right?
But let’s dig even more in the health benefits of sweet potatoes.
Sweet potatoes contain a wealth of orange-hued carotenoid pigments.
In some studies, sweet potatoes have been shown to be a better source of beta-carotene than green leafy vegetables.
Yet beta-carotene only begins to tell the story of sweet potato antioxidants. Particularly in purple-fleshed sweet potato, antioxidant anthocyanin pigments are abundant. Cyanidins and peonidins are concentrated in the starchy core of part of purple-fleshed sweet potatoes.
Extracts from the highly pigmented and colorful purple-fleshed and purple-skinned sweet potatoes have been shown in research studies to increased the activity of two key antioxidant (enzymes-copper/zinc superoxide dismutase (Cu/Zn-SOD) and catalase (CAT).
What all these antioxidants do exaclty? Recent research has shown that particularly when passing through our digestive tract, sweet potato cyanidins and peonidins and other color-related phytonutrients may be able to lower the potential health risk posed by heavy metals and oxygen radicals.
That risk reduction is important not only for individuals at risk of digestive tract problems like irritable bowel syndrome or ulcerative colitis but for all persons wanting to reduce the potential risk posed by heavy metal residues (like mercury or cadmium or arsenic) in their diet.
Storage proteins in sweet potato also have important antioxidant properties.
These storage proteins-called sporamins-get produced by sweet potato plants whenever the plants are subjected to physical damage. Their ability to help the plants heal from this damage is significantly related to their role as antioxidants. Especially when sweet potato is being digested inside of our gastrointestinal tract, we may get some of these same antioxidant benefits.
Anti-Inflammatory Nutrients in Sweet Potato
Anthocyanin and other color-related pigments in sweet potato are equally valuable for their anti-inflammatory health benefits.
In animal studies, reduced inflammation following sweet potato consumption has been shown in brain tissue and nerve tissue throughout the body.
What's equally fascinating about color-related sweet potato phytonutrients is their impact on fibrinogen.
Fibrinogen is one of the key glycoproteins in the body that is required for successful blood clotting. With the help of a coagulation factor called thrombin, fibronogen gets converted into fibrin during the blood clotting process. Balanced amounts of fibrinogen, thrombin and fibrin are a key part of the body's health and its ability to close off wounds and stop loss of blood.
Blood Sugar Benefits
What's fascinating about sweet potatoes is their ability to actually improve blood sugar regulation-even in persons with type 2 diabetes. While sweet potatoes do contain a valuable amount of dietary fiber and if boiled or steamed can carry a very reasonable glycemic index (GI) rating of approximately 50, it may not be either of these factors that explains their unusual blood sugar regulating benefits.
Recent research has shown that extracts from sweet potatoes can significantly increase blood levels of adiponectin in persons with type 2 diabetes. Adiponectin is a protein hormone produced by our fat cells, and it serves as an important modifier of insulin metabolism. Persons with poorly-regulated insulin metabolism and insulin insensitivity tend to have lower levels of adiponectin, and persons with healthier insulin metabolism tend to have higher levels.
Other Health Benefits
One of the more intriguing nutrient groups provided by sweet potatoes-yet one of the least studied from a health standpoint-are the resin glycosides. These nutrients are sugar-related and starch-related molecules that are unusual in their arrangement of carbohydrate-related components, and also in their inclusion of some non-carbohydrate molecules. In sweet potatoes, researchers have long been aware of one group of resin glycosides called batatins.
But only recently have researchers discovered a related group of glycosides in sweet potato called batatosides (including batatodide III, batatoside IV, and batatoside V). In lab studies, most of these sweet potato glycosides have been shown to have antibacterial and antifungal properties. To what extent these carbohydrate-related molecules in sweet potatoes can provide us with health benefits in these same antibacterial and antifungal areas is not yet clear. But we expect to see increasing interest in sweet potato's batatins and batatosides and their potential to support our health.
I hope that by now you’re convinced to include sweet potato in your diet...if not I don’t know what else to say.
Well, in reality there is one more thing: have you ever tried sweet potato fries? They are one of the best thing on the planet and even if fried sweet potatoes retain most of their incredible nutritional value!