What's to know about sweet potatoes?

Some people use the terms “sweet potato” and “yam” interchangeably. However, they are not related. Yams have a drier texture and a more starchy content than sweet potato.

This article looks at the nutritional value and possible health benefits of sweet potato. It also provides some tips on incorporating sweet potato into the diet, as well as some health risks.

Benefits

Sweet potato may offer a variety of health benefits. Here are some of the ways in which they may benefit a person’s health:

Improving insulin sensitivity in diabetes

In one 2008 study, researchers found that an extract of white skinned sweet potato improved insulin sensitivity in people with type 2 diabetes.

Earlier, in 2000, laboratory rats consumed either white skinned sweet potato or an insulin sensitizer, called troglitazone, for 8 weeks. The levels of insulin resistance improved in those that consumed the sweet potato.

However, more studies in humans are necessary to confirm these benefits.

The fiber in sweet potatoes is also important. Studies have found that people who consume more fiber appear to have a lower risk of developing type 2 diabetes.

A 124 gram (g) serving of mashed sweet potato, or around half a cup, will provide about 2.5 g of fiber.

The 2015–2020 Dietary Guidelines for Americans recommend that adults aged 19 years and above consume 22.4 g to 33.6 g of fiber each day, depending on their age and sex.

Learn about the best foods for diabetes here.

Maintaining healthful blood pressure levels

The American Heart Association (AHA) encourage people to avoid eating foods that contain high amounts of added salt, and to instead consume more potassium-rich foods to maintain a healthy cardiovascular system.

A 124 g serving of mashed sweet potato provides 259 milligrams (mg) of potassium, or around 5% of the daily requirements for an adult. Current guidelines recommend that adults consume 4,700 mg of potassium per day.

Get more tips on foods to lower blood pressure here.

Reducing the risk of cancer

Sweet potatoes are an excellent source of beta-carotene. This is a plant pigment that acts as a powerful antioxidant in the body. Beta-carotene is also a provitamin. The body converts it into the active form of vitamin A.

Antioxidants may help reduce the risk of various types of cancer, including prostate and lung cancer.

Antioxidants such as beta-carotene can help prevent cellular damage caused by unstable molecules called free radicals. If levels of free radicals in the body get too high, cellular damage can occur, increasing the risk of some conditions.

Obtaining antioxidants from dietary sources may help prevent conditions such as cancer.

Can some foods help prevent cancer? Find out here.

Improving digestion and regularity

The fiber content in sweet potatoes can help prevent constipation and promote regularity for a healthy digestive tract.

Also, multiple studies have linked high dietary fiber intake with a reduced risk of colorectal cancers.

Why is dietary fiber important? Learn more here.

Protecting eye health

As mentioned above, sweet potatoes are a good source of provitamin A in the form of beta-carotene. After the age of 18, the Dietary Guidelines recommend an intake of 700 mg of vitamin A per day for women and 900 mg per day for men. Vitamin A is important for protecting eye health.

According to the Office of Dietary Supplements (ODS), a baked sweet potato in its skin will provide around 1,403 mcg of vitamin A, or 561% of a person’s daily requirement.

Vitamin A also acts as an antioxidant. Together with other antioxidants, it can help protect the body from a variety of health conditions.

Learn more here about vitamin A.

Boosting immunity

One 124 g serving of sweet potato provides 12.8 mg of vitamin C. Current guidelines recommend a daily intake of 75 mg of vitamin C for adult women and 90 mg for adult men.

A person who consumes little or no vitamin C can develop scurvy. Many of the symptoms of scurvy result from tissue problems due to impaired collagen production.

Vitamin C also supports the immune system and enhances iron absorption. A low vitamin C intake may increase a person’s risk of iron deficiency anemia.

Find out more about vitamin C and why we need it here.

Reducing inflammation

A rodent study from 2017 suggests that an extract of purple sweet potato color may help reduce the risk of inflammation and obesity.

Sweet potatoes contain choline, a nutrient that helps with muscle movement, learning, and memory. It also supports the nervous system.

A 2010 study found that taking high dose choline supplements helped manage inflammation in people with asthma. However, this does not necessarily mean that choline from sweet potatoes will have the same impact.

Nutrition

A 124 g serving of mashed sweet potato contains around 98.7 g of water.

The table below shows the nutrients in sweet potato and the recommended daily intakes for adults. Exact requirements will depend on age, sex, and activity levels (for calories).

Sweet potato also contains B vitamins, calcium, and other essential vitamins and minerals.

Eating sweet potato skin can increase its nutritional value. The color of the skin can vary from white to yellow and purple to brown. However, whatever color it is, it will provide additional nutrients.

Tips

When buying and cooking sweet potatoes, it is important to check that the potato is firm with smooth, taut skin.

Also, always store them in a cool, dry place for no longer than 3–5 weeks.

Cooking tips

Roast sweet potatoes to bring out their natural flavor, and eat them without toppings. Sweet potatoes have a naturally sweet and creamy taste.

To roast them around a campfire or on a barbecue, wrap them in aluminum foil and place in the dying coals. Leave for around 50–60 minutes, until a fork slides into them easily.

People who do not plan to eat the skins can put the potato into the coals without wrapping it in foil.

To prepare a sweet potato quickly, prick it with a fork, wrap it in a paper towel, and put it in a microwave on high heat until soft.

If a person wants to add a topping, try:

• a sprinkling of cinnamon, cumin, or curry powder
• a spoonful of low fat cottage cheese or Greek yogurt
• a drizzling of olive oil

Other ways to incorporate sweet potato into the diet include adding roasted sweet potatoes and pecans to a salad and topping it with balsamic vinegar, and adding sweet potato to pancakes or hash browns.

Sweet potato recipes

Try these simple and healthful sweet potato recipes:

• Roasted sweet potato fries
• Sweet potato chips
• Heart healthy chipotle chili
• Sweet potato hummus

Risks

Sweet potatoes contain potassium. A high potassium intake may not be suitable for people who take beta-blockers. Doctors commonly prescribe these for heart disease, and they can cause potassium levels to rise in the blood.

People with kidney problems should also take note of how much potassium they consume. Consuming too much can be harmful to those with kidney problems. For example, severe complications can arise if a person with impaired kidney function consumes more potassium than their kidneys can process.

Another risk to be aware of is that some fruits and vegetables are susceptible to contamination with pesticides. Every year, the Environmental Working Group rank products according to their likelihood of contamination. In 2019, sweet potatoes ranked 31st.

Buying organic products or growing them at home are the best ways to minimize the risk of contamination.

There is a selection of sweet potato and sweet potato products available for purchase online.