Health Benefits Of Sweet Potatoes

Introduction

Sweet potato (Ipomoea batatas) is a sweet-tasting, starchy root vegetable that can be used in a variety of recipes. It has a thin, brown outer layer and bright-coloured flesh that is usually orange but can also be white, purple or yellow. As well as being extremely tasty, sweet potatoes have numerous nutrients as they are a good source of vitamin C, vitamin A, fibre and antioxidants. Studies have shown that they also provide many health benefits including improving blood sugar regulation, digestive health, eye health, immune function and even reducing the risk of cancer. When compared to white potatoes, sweet potatoes are considered the healthier choice.¹

This article will explore the many health benefits of sweet potatoes and advise you on how you can easily add this sweet vegetable to your diet. 

About sweet potatoes

Health benefits of sweet potatoes

Antioxidant properties

Sweet potatoes are a good source of vitamin A and vitamin C which means that they are packed with antioxidants. Antioxidants protect the body against free radicals by inhibiting oxidation. This in turn protects the body against chronic diseases such as cancer, heart disease, lung disease, age-related eye disease and early death. Interestingly, purple sweet potatoes have the highest source of antioxidants as a result of the pigment that gives it its bright colour¹.

Studies have shown that stronger antioxidant activities are found in the peel of white and purple sweet potatoes compared to their flesh. Therefore, it is recommended that you scrub sweet potatoes well before cooking instead of peeling them to get the most benefit¹.

Reduces the risk of cancer

It is known that eating a healthy diet can reduce the risk of cancer. Fruit and vegetables high in antioxidants often have anti-cancer properties. Studies have found that the antioxidant activity of sweet potatoes helps reduce the oxidative process caused by free radicals and therefore reduces the risk of cancer. These studies found that sweet potato has preventative properties against colorectal, breast, bladder, and pancreatic cancers¹.

Anti inflammatory properties

Purple sweet potato contains high amounts of anti-inflammatory compounds that have been found to prevent inflammation at a cellular level. Chronic inflammation is detrimental to our health and increases the risk of many chronic diseases such as heart disease, obesity, type 2 diabetes and cancer. A study found that these sweet potatoes had anti-inflammatory properties that could stop the growth of some cancer cell lines such as breast cancer, colon cancer and gastric cancer².

Improves eye health

Sweet potatoes are a rich source of beta-carotene which is the pigment that gives this vegetable its bright orange flesh. Our body converts beta-carotene into vitamin A which is a vitamin that provides protection against many diseases as well as improving eye health. Our body uses vitamin A to form light-detecting receptors in our eyes which is important for night vision and maintaining the health of the eye. Anthocyanins, a specific group of antioxidants found in sweet potatoes, have also been shown to be beneficial to the eyes. Interestingly, purple sweet potatoes contain higher levels of anthocyanins than other varieties.^1,3

Supports immune function

Sweet potatoes are also known to support immune function because they are a good source of beta-carotene. Beta-carotene, when converted into vitamin A, supports immune function by stimulating the production and activity of white blood cells, maintaining healthy endothelial cells and regulating cell growth and division.^1,4

Improves blood sugar regulation

Interestingly, another health benefit of sweet potato is its role in the regulation of blood sugar levels. This is because their high fibre content makes them a slow-burning starch which means they do not spike insulin and blood sugar levels. Studies have shown that the starch in sweet potatoes can improve insulin sensitivity and resistance.¹

Nutrients we can get from sweet potatoes

An 80g serving of steamed sweet potato provides:³

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

 Fibre

Cooked sweet potato is high in dietary fibre with a medium sweet potato containing around 3 grams. The dietary fibre content consists of two types: soluble fibre and insoluble fibre. Soluble fibre, such as pectin, increases fullness and reduces spikes in blood sugar levels. Dietary fibre in sweet potatoes is beneficial for type 2 diabetics as it stabilises blood sugar levels and lowers insulin resistance.¹

Vitamins and minerals

Sweet potatoes contain an abundance of vitamins and minerals which are beneficial for our health⁴ 

•  Vitamin A – supports our immune system, improves eye health and keeps the skin and lining of certain parts of our body healthy
• Vitamin C – protects cells, maintains healthy skin, blood vessels, bones and cartilage and helps with wound healing
•  Potassium – helps control the balance of fluids in our body, supports normal blood pressure and helps muscles to contract
• Vitamin B6 – helps the body to use and store energy from protein and carbohydrates and helps the body form haemoglobin
• Manganese – important for growth, development and metabolism
• Vitamin E – supports the immune system and helps maintain healthy skin and eyes

Plant compounds

Sweet potatoes also contain some plant compounds that are beneficial for health:^1,4

• Beta-carotene – an antioxidant that our bodies convert into vitamin A
•  Anthocyanins – a group of antioxidants found in purple, blue and red fruit and vegetables
• Chlorogenic acid – a polyphenol antioxidant compound that protects the body against oxidative stress

How to include sweet potatoes in our diet

Sweet potatoes can be eaten whole or peeled and the leaves of the plant can also be eaten too. They can easily replace white potatoes and can be incorporated into your diet in many different ways. They can be steamed, boiled, baked, fried and roasted. Although cooking sweet potato increases its vitamin C content, it also reduces its beta-carotene levels. However, findings show that boiling sweet potatoes retains more beta-carotene compared to baking. In fact, up to 92% of the nutrients can be retained by limiting the cooking time and cooking with the skin on helps to reduce the leaching of nutrients such as beta-carotene and vitamin C.⁵

Different ways to add sweet potatoes to your daily diet include:³

• Mashed sweet potato
• Pureed sweet potato as a base for soup
• Oven-baked sweet potato wedges
• Sweet potato fries
• Add into a smoothie
• Bake and drizzle with cinnamon and maple syrup
• Add into desserts for a healthy twist

How much is enough?

Side effects and how much to consume

An 80g serving of sweet potato, or one medium sweet potato, counts as one of your five a day and is enough to provide you with a variety of nutrients.³

Sweet potatoes are a great addition to your diet and are generally safe for most people, with only a few reported cases of allergy. However, they are a high source of oxalates which are compounds that bind calcium and other minerals. Consuming too much oxalates in your diet may increase your risk of kidney stones. People who suffer from kidney stones or are at high risk for developing them may need to limit their intake of sweet potatoes and other food high in oxalates. It is advised you refer to your GP if you have any dietary concerns based on existing health conditions.³

Summary

In summary, sweet potatoes are starchy, sweet-tasting vegetables that have a range of health benefits. They are considered a healthier alternative to white potatoes and can be easily added to your diet in many different ways. Their high dietary fibre content means they are excellent at regulating blood sugar levels and lowering insulin resistance. As well as this, they are also a good source of antioxidants which supports the immune system, improves eye health and reduces the risk of a range of chronic diseases such as cancer, heart disease and diabetes.

Sweet potatoes can be steamed, boiled, baked, fried and roasted and can be added to a range of recipes. Although they are generally considered safe to consume, sweet potatoes contain high levels of oxalates which may increase your risk of kidney stones. Overall, sweet potatoes are packed with many nutrients and are an excellent addition to your diet.