By: Susan Joy
How do sweet potatoes compare with regular white potatoes?
Well for starters, sweet potatoes are the orange or reddish coloured root vegetable you see at your supermarket or farmer’s market. They are a member of the morning glory family, and not related to white potatoes.
Sweet potatoes are usually longer and tapered at the ends, and can range in colour from tan to orange, red, or purple. Sweet potato’s flesh inside also varies from white to orange or reddish-orange, to purple-coloured. Sweet potatoes are also usually softer and sweeter when cooked than regular white potatoes.
White potatoes are something we are all pretty familiar with. White potatoes come from the “nightshade” group of vegetables, which is related to tomatoes, capsicum, chilli peppers, paprika and eggplant.
While there are literally thousands of different types of potatoes in the world, in general, the types of potatoes we see here in Australia are classified as russet potatoes, red potatoes, white potatoes, yellow potatoes and purple potatoes.
Sweet potatoes and regular white potatoes are from different plant families and are not related. Sweet potatoes have become much more common and popular in the past ten or so years, and are often served baked, mashed or roasted. They are also a great alternative to fries and an alternative to regular mashed potatoes. Sweet potatoes are often pureed and used in recipes like soups and desserts and to thicken sauces (I use them to thicken my Seafood Chowder recipe). I also use a vegetable spiralizer and make sweet potato noodles to use in place of pasta.
Sweet potato nutrition
Sweet potatoes contain a lot of nutrients (which is why they are so popular) including a massive amount of beta-carotene, the nutrient that our bodies turn into vitamin A. Sweet potatoes also contain about 35-40% of our required daily vitamin C, manganese, vitamin B6, potassium, copper, niacin, thiamine and magnesium.
Sweet potatoes also help to stabilise blood sugar and help the body become more sensitive to insulin. This is due partly because of the high fibre content, which slows the absorption of sugar into the body, and probably due to the high amounts of antioxidants, as well.
Antioxidants also help to reduce other chronic diseases including diabetes, heart disease, and cancer. The orange colour in sweet potatoes means it is especially high in the antioxidant beta-carotene, so choose the most colourful ones.
Sweet potatoes are also known to boost brain function and improve memory.
Since sweet potatoes have about 400% of the precursor to vitamin A, they are especially good for boosting the immune system, protecting vision, and helping the skin.
White potato nutrition
White potatoes do have some healthy minerals, fibre and carbohydrates in them, but definitely are not the superstars that sweet potatoes are. White potatoes belong to a totally different plant family, are definitely different looking than sweet potatoes and have a whole different set of nutrients.
White potatoes contain vitamin C, folate, vitamin B6, potassium, manganese, but not the high levels of vitamin A or antioxidants that sweet potatoes have.
Blood sugar and the glycemic index: Sweet potatoes have a medium GI value, around 60 and White potatoes have a high GI score at 76.
The glycemic index is based on a scale of how quickly a food causes your blood sugar levels to increase. The scale lists foods that have a rating of:
- 50 or less as low
- 51 to 69 as medium
- 70 and above as high
Foods with a low GI tend to raise your blood sugar slowly and steadily, while foods high on the index cause quicker spikes.
So, when looking at both types of potato, gram for gram, white potatoes will cause a sharper spike in blood sugar when eaten. So, if you are diabetic or trying to keep your blood sugar low, you are better off eating sweet potatoes. Sweet potatoes are also higher in fibre than regular potatoes.
Which is best?
So—the winner in terms of nutrition is sweet potatoes!
However, white potatoes can be a healthy addition to the diet, as long as you don’t need to restrict your starchy carbs or need to avoid nightshade vegetables. It’s also best to not consume white potatoes if you have an autoimmune illness, diabetes or fatty liver disease. Preparation is an important factor, fries cooked in unhealthy oils is not going to be healthy (cooking in an air fryer is a better option), so eat baked instead of fried.
If you are looking for ways to add more sweet potato to your family’s diet, check out some of my recipes below:
Article supplied with thanks to The JOYful Table.
About the Author: Susan is an author of The JOYful Table cookbook containing gluten & grain free, and Paleo inspired recipes for good health and wellbeing.