What is a sweet potato?

The sweet potato (Ipomoea batatas) is a starchy, sweet-tasting root vegetable. It has a thin, brown outer skin with bright-coloured flesh – most commonly orange, but other varieties include white, purple or yellow. You can eat sweet potatoes whole or peeled and the leaves of the plant are edible, too.


Although, they may both be called ‘potatoes’, sweet and regular white potatoes are not related. Botanically, the sweet potato belongs to the bindweed or morning glory family, whereas the white potato sits in the nightshade family.

Benefits of sweet potato include:

  • May reduce the risk of cancer
  • May support digestive health
  • May help manage type-2 diabetes
  • Good for eye health
  • May support immune function
  • May support the brain and nervous system
  • May support heart health
  • May be liver protective
  • Are low in fat
  • Are nutritional value for money

Discover our full range of health benefit guides or check out some of our best sweet potato recipes, from our feta & kale loaded sweet potato to our spinach sweet potato & lentil dhal.

Nutritional profile of sweet potato

An 80g serving of sweet potato (steamed) provides:

More like this
  • 67kcal / 285kj
  • 0.9g protein
  • 0.2g fat
  • 16.3g carbohydrates
  • 6.7g sugar
  • 280mg potassium
  • 3012 mcg carotenes
  • 14mg vitamin C

An 80g serving of sweet potato, or one medium potato, counts towards one of your five-a-day, unlike white potato, which does not.

Read more about what counts towards your five-a-day.

Is sweet potato a carb?

Edible roots like sweet potato are naturally rich in carbs, as well as fibre. This is because they act as storage organs for the plant, storing up energy for periods of dormancy. Root vegetables vary in their balance of starches, sugars and other carbs, including fibre, with sweet potato being richer in total carbs, sugar and fibre but lower in starch, than regular white potatoes.

Although sweet potatoes are a source of carbs, being a tuber they contain high amounts of other health-promoting phytonutrients.

Cooking sweet potatoes in an oven

How does cooking affect the nutritional value of sweet potato?

Cooking sweet potato does reduce its beta-carotene levels, although boiling appears to have a higher retention compared to baking. The good news, however, is that cooking sweet potato appears to increase its vitamin C content.

Health benefits of sweet potato

1. May reduce the risk of cancer

While there are no ‘superfoods’ that can prevent cancer and certain risk factors for cancer are unrelated to diet, there is evidence that eating a healthy diet may reduce the risk of cancer. Fruit and vegetables are high in antioxidants, compounds that help defend the body against damage by ‘free radicals’. Studies have suggested that the antioxidants in the peel of sweet potatoes, especially purple sweet potato, may help reduce this oxidation process, thereby reducing the risk of cancer. To get the most from your sweet potatoes simply scrub well before cooking.

2. May support digestive health

Sweet potatoes are high in fibre, which has been shown to promote a healthy digestive system. Much of the research so far has been conducted on animals, but it would appear that high levels of plant sterols (phytosterols) in sweet potatoes may have a protective effect on the digestive system and may be useful in the prevention and management of duodenal and gastric ulcers, including those due to NSAIDS (non-steroidal anti-inflammatory drugs, such as ibuprofen).

3. May help manage type-2 diabetes

Interesting findings suggest that moderate consumption of sweet potato and sweet potato leaves may improve blood sugar regulation in type-2 diabetes. Although, more evidence from well-designed trials is needed to validate these findings.

4. Good for eye health

Sweet potatoes are rich in beta-carotene – in fact, it’s what gives this root its bright-orange colour. When we eat beta-carotene, our body converts it to vitamin A, which is then used to form light detecting receptors in the eye. This is important for night vision and maintaining the health of the eye.

A study by Food & Nutrition Research found that purple sweet potatoes contain a specific group of antioxidants known as anthocyanins, which have also been shown to benefit the eyes.

5. May support immune function

Being rich in beta-carotene, sweet potatoes may also support immune function. This is because vitamin A is important for maintaining the integrity of the mucous membranes in the respiratory system and gut. Animal studies also suggest that polysaccharides (simple sugars) found in sweet potato, especially the purple variety, may stimulate immune responses and potentially regulate our adaptive (also known as acquired) immunity.

6. May support the brain and nervous system

Animal studies suggest protective plant compounds in sweet potatoes including phenols and anthocyanins may support the brain. They do this by helping minimise neurotoxicity and by promoting the production of brain-derived neurotrophic factor (BDNF). BDNF plays an important role in nerve growth as well as being essential for memory and learning.

7. May support heart health

Being a rich source of potassium, sweet potatoes help promote a healthy heart. Higher potassium intake helps manage sodium levels and as a result promotes healthier blood pressure, which may reduce your risk of heart disease.

8. May be liver protective

Plant compounds in sweet potatoes, including anthocyanins, may be liver protective, this is because they help lower inflammation and reduce free radical damage caused by oxidation.

9. Are low in fat

Interestingly, when boiled or baked, sweet potatoes are virtually fat-free. Root vegetables might be rich in carbs but contribute fewer calories than the equivalent portion of pasta or rice. What’s more, unlike pasta and rice, they contribute useful micronutrients, including beta-carotene, potassium and vitamin C.

10. Nutritional value for money

Sweet potatoes offer a favourable nutrient-to-price ratio and are an important staple across the world. They make a nutritious and filling addition to the diet and are popular with all age groups.

Sweet potato fries with guacamole

Are sweet potatoes safe for everyone to eat?

On the whole, sweet potatoes are an excellent addition to a balanced diet and appear to be safe for most people, with very few reported cases of allergy.

However, they do contain compounds called oxalates, which bind calcium and other minerals, inhibiting their absorption. Too many oxalates in the diet may cause kidney stones. If you have existing kidney stones or are at high risk of developing them, you should minimise your consumption of high-oxalate foods.

Overall, are sweet potatoes good for you?

Sweet potatoes are root vegetables that are an excellent source of vitamins, minerals and plant compounds, including beta-carotenes. They are good value for money, count as one of your 5 a day and make an easy, nutritious swap for other carb-rich staples.

If in doubt or you have concerns regarding your diet and health condition, refer to your GP or registered dietician.

Healthy sweet potato recipes

Sweet potato, coconut & lemongrass soup with coriander sambal
Sweet potato dhal with curried vegetables
Moroccan chicken with sweet potato mash
Spinach, sweet potato & lentil dhal
Jerk sweet potato & black bean curry
Spiced chicken, spinach & sweet potato stew
All our healthy sweet potato recipes

Enjoyed this? Read more:

What are anthocyanins and why are purple foods so healthy?
Top 5 health benefits of potatoes
The health benefits of bananas
Top 5 health benefits of carrots
Top 5 health benefits of parsnips

This article was last reviewed on 27 March 2024 by Kerry Torrens.

Nicola Shubrook is a nutritional therapist and works with both private clients and the corporate sector. She is an accredited member of the British Association for Applied Nutrition and Nutritional Therapy (BANT) and the Complementary & Natural Healthcare Council (CNHC). Find out more at urbanwellness.co.uk.

Kerry Torrens BSc. (Hons) PgCert MBANT is a registered nutritionist with a post graduate diploma in personalised nutrition & nutritional therapy. She is a member of the British Association for Nutrition and Lifestyle Medicine (BANT) and a member of the Guild of Food Writers. Over the last 15 years, she has been a contributing author to a number of nutritional and cookery publications, including Good Food.


All health content on goodfood.com is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other healthcare professional. If you have any concerns about your general health, you should contact your local healthcare provider. See our website terms and conditions for more information.

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