Sweet potatoes offer health benefits year-round, not just in the fall and in winter. Learn more about how to incorporate them into your diet, as well as their nutrient value.

1. Whole Food Therapy Presentations
Moira Khouri, NC, MH, HHP, CCP, RYT
The Health Benefits of Sweet Potatoes
Introduction
Sweet Potatoes are much overlooked and usually only found at dinner when prepared for
Christmas and Thanksgiving celebrations here in North America. Due to the increasing
awareness of the nutritional importance of complex carbohydrates in our diets this hearty
vegetable is enjoying a much deserved renaissance. The humble sweet potato is being
featured in many dishes including breads and desserts due to its sweet flavor. Its powerful
nutritional properties make this ancient vegetable a very healthy and economical addition to
your diet.
History
Commonly thought to be a root vegetable, the sweet potato is actually a tuber, from the
Convolvulaceae or morning glory family, Ipomoea batatas, not a member of the Solanaceae
family of potatoes or a root vegetable at all. It is actually one of over four hundred
varieties of sweet potatoes that range in color from white to yellow to orange. Its thin skin
may be colored white, yellow, orange, red or purple. Their shape may be potato-like, short
and bulky, or long and narrow with pointed ends. Sweet Potatoes are grouped into two
categories according to their texture when cooked, either firm, dry and mealy, or soft and
moist. Their taste is usually starchy and somewhat sweet, but can differ in the varieties.
As a side note, its darker sweeter cousin, the Yam, is actually named from the African word
nyami, for the root from the Dioscorea family of plants. Their taste and texture are distinctly
different from the many varieties of sweet potatoes.
With a very long culinary history sweet potatoes were native to Central America. It is
estimated that they have been around since prehistoric times, for about 8,000 to 10,000
years. They have been found in Peruvian caves dating back 10,000 years ago which makes
them possibly one of the oldest vegetables. Christopher Columbus is credited with being
the first explorer who transported them to Europe. Later, in the sixteenth century the
Portuguese and Spanish explorers brought them to Africa, India, Indonesia and southern
Asia. By the mid-twentieth century the sweet potato was being cultivated in North America
as a staple vegetable food and misnamed “yam” to distinguish it from the commonly
consumed white potatoes.
Sweet potatoes have also risen to popularity in the cuisines of Latin America and India, and
are also commercially produced in China, Indonesia, Vietnam, Japan, India and Uganda.

2. The Many Nutritional Properties of Sweet Potatoes
Vitamins and Minerals
Nutritional power foods prized for their vitamin, mineral and anti-oxidant properties, sweet
potatoes are an excellent source of beta-carotene (Vitamin A). The high amount of beta-
carotene found in sweet potatoes, between 100-1600 mcg in 3.5 ounces, has been found to
increase blood levels of Vitamin A substantially. Uptake of beta-carotene has been found
improve with about 3 to5 grams of fat eaten at the same meal (think extra virgin olive oil,
organic coconut oil, organic butter). Sweet potatoes are also a good source of Vitamin B2
(Riboflavin), B6 (Pyridoxine), Vitamin C, and the minerals manganese, potassium, copper, biotin,
B5 (pantothenic acid) and dietary fiber. Here’s a brief list of the biological actions these
vitamins and minerals assist in:
Vitamin A - Antioxidant and immunity booster. Helps form collagen in the bone matrix.
Necessary for healthy skin inside and out, and adrenal function. Protects against many forms of
cancer. Essential for night vision.
Vitamin B2 – Helps convert fats, sugars and protein into energy. Helps repair and maintain
healthy skin, inside and out. Helps regulate body acidity and important for the growth of hair
and nails.
Vitamin B5 –Involved in energy production. Controls fat metabolism. Essential for brain and
nerves. Helps make anti stress hormones (steroids). Maintains healthy skin and hair.
Vitamin B6 - Essential for protein digestion and utilization, brain function and hormone
production. Helps balance sex hormones, normalizes progesterone. Antidepressant and
diuretic. Helps control allergic reactions. Improves liver detoxification.
Vitamin C – Antioxidant. Strengthens immunity and helps to fight infections. Detoxifies
pollutants, and protects against cancers and heart disease. Protects against PCB and heavy
metal toxicity. Helps to reverse atherosclerosis. Helps form collagen in the bone, skin and
veins, and keeps joints firm and strong. Reduces risk of bone fracture in smokers.
Manganese - Helps form collagen in the bone matrix, cartilage, tissues and nerves. Activates
more than 20 enzymes, including the antioxidant system and increases superoxide dismutase
which eliminates free radicals. Stabilizes blood sugar, promotes healthy DNA and RNA.
Essential for reproduction and red blood cell synthesis. Important for insulin production,
reduces cellular damage and is required for brain function.
Potassium - Decreases blood pressure; helps to prevent stroke. Enables nutrients to move into
and waste products to move out of cells. Promotes healthy nerves and muscles, maintains fluid
balance in the body, and relaxes muscles. Helps with the secretion of insulin for blood sugar

3. control and helps produce constant energy. Involved in metabolism, maintains heart
functioning, and stimulates gut movements to encourage proper elimination.
Copper - Improves cholesterol metabolism. Helps form collagen in the bone matrix. Needed for
formation of the myelin sheath around nerves. A constituent of an antioxidant enzyme involved
in some inflammatory reactions (copper/zinc superoxide dismutase) by increasing superoxide
dismutase which eliminates free radicals.
Biotin – Lowers blood sugar levels. Improves insulin resistance. Helps the body utilize fats.
Assists in promoting healthy skin, hair and nails.
A 3.5 ounce (100 gram) serving provides 120 calories, 2 grams of protein, 24 grams of
carbohydrate, 3 - 4 grams of fiber and only 8.4 grams of sugar, 13 mg sodium with Vitamin A
20,063 IU, Vitamin B6 0.3mg, Beta Carotene 12 mg, Vitamin C 23 mg, Copper 0.2 mg and
Manganese 0.4mg.
Frozen or canned sweet potatoes have greatly reduced nutrient values of Vitamin B
and C. A baked frozen sweet potatoe will have 50% less Vitamin C and 25% less beta
carotene than a fresh one.
Antioxidants
Carotenoids act as antioxidants that neutralize free radicals and enhance immunity. High
intake is associated with lower rates of several cancers. Choose darker orange sweet
potatoes or the dark purple variety for a higher carotenoid intake.
The purple fleshed variety is very high in anthocyanin pigments. These cyanidins and peonidins
are found in concentrated amounts in their starchy core, and are even more concentrated in
the skins. These are believed to increase the activity of two key anti-oxidant enzymes,
copper/zinc superoxide dismutase and catalase. In one study the antioxidant activity was 3.2
times higher than in blueberries. While transiting the digestive system these may be able to
lower the health risks of exposure to heavy metals such as mercury, cadmium and arsenic, and
oxygen radicals, important for all of us, but especially to those at risk for irritable bowel
syndrome and ulcerative colitis.
Anti-inflammatory
Anthocyanins and other colorful pigments in sweet potatoes have important anti-inflammatory
properties that act specifically by reducing the activation of nuclear factor-kappa (NF-I0B),
cyclooxygenase-2 (COX-2), and formation of malondialdehyde (MDA). This plays a key role
preventing unwanted inflammation. While inflammation when needed for healing is good,

4. excess inflammation leads to heart diseases, including atherosclerosis, arthritis, diabetes and
other inflammatory conditions.
Steaming preserves the anthocyanins, by deactivating the peroxidase enzymes that
can break down anthocyanins.
Roasting or boiling gives better effects on blood sugar management such as a lower
glycemic index, or GI value.
Another health benefit from the phytonutrients in sweet potatoes is their positive effect on
fibrinogen, one of the key glycoproteins required for blood clotting. A blood clotting factor,
thrombin, works with fibrinogen in the conversion to fibrin. The balance of these three aids in
blood clotting to close off wounds and prevent loss of blood. An excess fibrin can trigger
inflammation and damage to the central nervous system, contributing to health conditions such
as multiple sclerosis in which there is a breakdown of the myelin nerve sheath, and researchers
are hopeful such damage can be reduced through the balancing effects of sweet potato
pigments to reduce inflammation and fibrinogen levels.
Anti Diabetic
Sweet potatoes have the ability to improve blood sugar regulation, even in people with Type
2 diabetes. They contain a good amount of dietary fiber, over 3 grams in a medium sweet
potato, which slows down the delivery of sugars into the blood stream, and have a glycemic
index rating or 50 when boiled or steamed. While this is all good, it is also their ability to
significantly increase blood levels of adiponectin in people with Type 2 diabetes.
Adiponectin is a protein hormone produced by our fat cells that is a modifier of insulin
metabolism. People with poorly regulated insulin metabolism and insulin insensitivity have
lower levels of adiponectin which may be helped by eating sweet potatoes.
Antibacterial and Antifungal
Another nutrient found in sweet potatoes is the resin glycosides, sugar-related and starch-
related molecules that are unusual in two ways, their arrangement of carbohydrate-related
compounds, and their inclusion of non-carbohydrate molecules. One group of resin
glycosides called batatins (batatin I and II) and a related group called batatosides
(batatosides III, IV and V) have been shown to have antibacterial and antifungal properties.
These need further study to determine the extent of their potential to provide health
benefits.

5. Glycemic Load
Sweet Potatoes have a glycemic load of 17 per a 5.3 ounce serving. Glycemic load refers to how
fast carbohydrates convert into glucose and determines whether a food is slow releasing or fast
releasing. Foods with a GL of 10 or less are considered the best to manage blood sugar, with
the ideal consumption being no more than a total of 50 GL points per day or 40 GL points per
day if you wish to lose weight. Fiber content slows down the conversion to glucose.
ORAC Rating
Sweet potatoes have an ORAC rating of 301 per 1/2 cups, cooked. ORAC units stand for Oxygen
Radical Absorbance Capacity, the antioxidant power of a food, the foods ability to counteract
free radicals to protect against cancer, heart disease and aging. It is estimated that we should
ideally have 3500 ORAC units daily, however a higher amount of 5000 – 6000 will provide
greater protection.
Contraindications
Sweet potatoes contain high levels of Oxylate. Individuals with a history of Oxylate-
containing stones should not consume large amounts of sweet potatoes.
Do not buy those with a greenish tint that may indicate that the toxic alkaloid solanine may
be present. Solanine has an unpleasant taste and may also cause health problems such as
circulatory and respiratory depression, headaches and diarrhea.
Selecting, Harvesting and Storing
Choose high quality sweet potatoes that are firm and have the characteristics of their
variety, are heavy for their size and are smooth, hard and free of bruises and black spots
which may be mold. Check the tips as this is where decay will usually begin. For higher
carotene content choose darker skins. Do not buy wilted, soft, leathery or discolored sweet
potatoes.
Store sweet potatoes in a cool, dark, well ventilated place and they will keep fresh for up to
ten days. Store loose, not in plastic bags. Keep away from sunlight exposure and
temperatures above 60 degrees F to prevent sprouting and fermentation. Do not store raw
sweet potatoes in the fridge as this may cause them to easily mold. Store refrigerated
cooked sweet potatoes for between three to five days.
To prepare, wash under cold running water scrubbing gently with a soft vegetable brush
right before cooking. If using organic sweet potatoes soak them in a mild veggie wash
solution then scrub or peel under cool running water. Remove deep bruises and peel with a
vegetable peeler removing only a thin layer of skin to retain nutrients. Do not cut with a
carbon steel-knife, or cook in aluminum or iron pot as these metals can cause discoloration.

6. Do-It-Yourself Veggie Wash
1 tbls. organic lemon juice
10 drops grapefruit seed extract
2 tbls. baking soda
1 cup filtered water
3/4 cup white vinegar
Mix well in a sprayer bottle. Shake before use. Spray produce (except mushrooms, because
they absorb and retain water) and let sit for 5-10 minutes. Rinse well before eating.
Recipes From Around the World
Roasted Sweet Potatoes & Carrots
Roasting intensifies the natural sugars in both vegetables, and the added spice makes this a
perfect holiday side dish you will be asked to make time and again. It is my own family
favorite tradition for Christmas dinners here in Canada.
Ingredients
2 ½ pounds of organic sweet potatoes, preferably the darkest orange available
1-2 pounds of organic carrots
2 Tbsp. coconut oil, melted, plus oil to cover baking dish lightly
1 tsp. raw honey
1 tsp. ground cinnamon
½ tsp. ground Cardamom
sea salt and fresh ground pepper to taste
Preheat the oven to 450 F and lightly oil a glass rectangle baking sheet. Slice the sweet
potatoes and carrots into rounds about ¼ - ½ inch thick. If working with large sweet
potatoes you may want to cut each round in half to reduce cooking time. Mix oil, spices and
honey. Place vegetables in a large bowl and toss with the oil and spice blend until all are
well covered. Layer vegetables evenly in the oiled baking dish, and place in oven to roast
for 10 minutes. Remove from oven and stir carefully turning over vegetables. Return to
oven and continue to roast until tender, checking every 5 minutes. Once they begin to turn
a light golden color on top remove from oven and serve.

7. Two Potato Gratin
This recipe is from the book Moosewood Restaurant Simple Suppers, Fresh Ideas for the
Weeknight Table, by The Moosewood Collective, a group of 19 people who own and operate
the Moosewood Restaurant, a famous natural foods vegetarian restaurant since 1973
located in Ithaca, New York. They develop recipes and write cookbooks, and are winners of
the James Beard awards. The recipe combines white and sweet potatoes for color and
flavor.
Ingredients
2 eggs
3 cups grated sweet potatoes and white potatoes
½ cup chopped scallions
2 tbsp. unbleached white flour
1 tsp. salt
¼ tsp. black pepper
1 cup grated dilled Havarti cheese
1 tbsp. butter
1 tbsp. vegetable oil
Preheat oven to 375 F. Beat the eggs in a large bowl. Add the potatoes, scallions, flour,
salt, pepper and half of the cheese and mix well. Heat the butter and oil in an ovenproof
skillet (10-12 inches) on medium-high heat. Spoon the potato mixture into the skillet and
spread evenly. Reduce heat to medium-low and cook for 10-12 minutes, until bottom is
nicely browned. Do not stir.
Transfer skillet to oven and bake for 15 minutes, until top is golden. Sprinkle the gratin
with the remaining cheese and continue to bake until the cheese is melted, about 5
minutes. Cut the gratin into wedges and serve hot.
Classic Indian Sweet Potato Pickle
This classic East Indian condiment is eaten with the main meal to accompany any meat or
fish, but also compliments vegetable dishes. It is called a pickle because like other Indian
pickles you eat a very small amount. The recipe is from the book Elegant & Inspired by
Vikram Vij, the owner of the famous Vij’s Indian Cuisine restaurants. The turmeric and
cayenne pepper in this recipe are also anti-inflammatory spices commonly used in Ayurvedic
Medicine.
Ingredients
1 ½ pounds sweet potatoes, cut in 1 ½ inch or 2 inch pieces
1/3 cup demerara sugar
3 Tbsp. Ghee (clarified butter)
½ tsp. Turmeric

8. ½ Tbsp. salt
½ Tsp. ground cayenne pepper
Preheat oven to 450 F. Combine sweet potatoes, sugar, ghee, turmeric, salt and cayenne in
a large bowl. Stir well and make sure the potatoes are well covered in the spice mixture.
Pour potatoes onto a baking tray, cover with aluminum foil and bake for 20 minutes.
Carefully remove the tray from the oven and remove the foil. Lightly stir to distribute ghee
and sugar evenly. Poke sweet potato with a knife to see if it is cooked. If sweet potato is
still slightly raw in the middle, replace foil and bake for another 5 minutes. Be very careful
not to overcook the sweet potatoes. Remove from oven, uncover immediately and stir
carefully.
Lebanese Sweet Potato and Okra Kebobs
This vegetable side dish recipe is from Lebanon, and combines the traditional vegetables,
Okra and onions with the more recently introduced sweet potato, and a time honored
cooking method. The recipe is from the book Lebanese Cooking, An Introduction to This
Special Middle Eastern Cuisine by Susan Ward.
Ingredients
24 small okra
3 medium sized sweet potatoes, peeled and each cut into eight pieces
24 small pickling onions
4 ounces olive oil
1 Tbsp. honey
Salt and freshly ground black pepper
½ tsp. ground cumin
Trim off the stem end of the okra, being careful not to cut into the seed chambers. Bring a
large saucepan of water to the boil. Drop in the sweet potato pieces and cook for 5
minutes. Add the onions and cook for 4 minutes, the add the okra and continue cooking
for 1 more minute. Drain the vegetables and plunge them into cold water to stop the
cooking. Leave to cool for a few minutes, then drain again and peel the onions.
Thread vegetables alternately on to 6 large or 12 small skewers. In a bowl, whisk together
the olive oil, honey, salt and pepper, and ground cumin. Baste kebobs with this mixture
and place them on a medium to hot grill over grey-ashed coals (or under a pre-heated grill).
Cook for 8 – 10 minutes, or until all the vegetables are tender, turning once and basting
with the oil and spice mixture occasionally. Serve immediately.
Mexican Camotes - “The Perfect Breakfast” (Ipomoea batatas)
This recipe is from the book The Art of Mexican Cooking, Traditional Mexican Cooking for
Aficionados by Diane Kennedy. The author credits this recipe to Senorita Esperanza, “her

9. oracle on all things sweet and an herbalist”. Her Camote is served as breakfast with a glass
of milk and considered to be the “perfect breakfast”.
When the camotes are dug up in the fall, spread them out, earth covered as they are, in the
sun for 5 days, turning them over from time to time. Then scrub them clean, spread them
out on a baking sheet, and bake in a 400 F oven until they are soft and their syrup starts to
exude, about 1 hour depending on size.
While the camotes are still hot, pack them down in an earthenware casserole (or if you are
in Michoacán you pack them down between layers of banana leaves), cover, and let them sit
overnight. The next day they should be soft with plenty of syrup. Eat them, skin and all.
References
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Moosewood Collective. Moosewood Restaurant Simple Suppers, Fresh Ideas for the
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Vij, Vikram and Dhalwala, Meeru. Elegant & Inspired Indian Cuisine. Vancouver, BC:
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