It is very common for people to mix up the names of vegetables that look and taste similar. As a result, it has become the norm to refer to sweet potatoes as yams or to yams as sweet potatoes. Linguistically speaking, these two words can be considered as synonyms of sort. Hence, it is not going to be a big deal if you use these words interchangeably. However, if you are interested in learning in depth about yams and cooking with yams, then you better not use the term sweet potatoes to describe them, at least not on a regular basis. Yams and sweet potatoes may have their share of similarities, but their distinct differences often go unnoticed.
Differences in Appearance
In terms of appearance, there are some evident differences between sweet potatoes and yams. As a general thumb rule, you should remember that sweet potatoes are smaller than yams, although there are a few exceptions that you may come across. In certain extraordinary cases, yams can massively outweigh sweet potatoes as some of them have been known to grow to masses as large as 100 lbs. The skin of the yam is also quite scaly and coarse compared to the smoother surface of sweet potatoes. Moreover, you can spot a few nodules on the skin of the yam. If you are able to notice these differences, you will probably not have a difficult time differentiating between the two on the basis of visual appearance.
Prevalence in UK and US
Yams and sweet potatoes have more or less equal market share in the United States. However, the former is more prevalent in the United Kingdom. This is because plenty of yams are ground in the Caribbean Islands. Since Britain has a large West Indian community, yams are imported into the United Kingdom in enormous quantities. Hence, they occupy more shelf space than sweet potatoes in most parts of Britain.
Origins of Yams and Sweet Potatoes
It is commonly believed that West Africa is the birthplace of yams, although there is concrete evidence to suggest that Asians may have been the first to cultivate this vegetable. Unlike yams, sweet potatoes have their origins in the West. Peru and Ecuador are the native lands of sweet potatoes. Since its initial cultivation, it has spread all across the world including several parts of Asia. The Indian subcontinent is well known for its abundance of yams. However, you aren’t going to find too many sweet potatoes in this region. Interestingly, the sweet potatoes and yams do not exactly share their genealogy. This is because they do not even belong to the same family of vegetables. The yam is a member of the lily family while sweet potatoes are closely related to Morning Glory and field bindweed. According to researchers, yams have been cultivated and consumed by human beings for more than 50,000 years.
According to the rules and regulations of the US Department of Agriculture, it is mandatory for every producer to label sweet potatoes as yam-sweet potatoes. Hence, you have to be careful about reading the label on the packaging of these edible roots.
Health Benefits and Nutritional Value
Both the vegetables have plenty of health benefits to offer to their consumers. The sweet potato is clearly “sweeter” as it contains more sugars such as glucose, fructose and sucrose. Hence, you will see a lot of classic American desserts that are based on the use of baked sweet potatoes. A good example of that would be the sweet potato casserole with toasted marshmallows. Furthermore, people in the United States love to use sweet potato side dishes as the perfect complement to Thanksgiving turkey.
When it comes to nutritional value or nutritional content, the sweet potato is deemed superior to the yam. This is because the amount of beta-carotene in sweet potatoes is higher than that found in yams. Both sweet potatoes and yams contain sufficient quantities of Omega-3 and Omega-6 fatty acids. Most of the foods that constitute the traditional Western diet do not have much Omega-3 on offer. Hence, yams and sweet potatoes can be an extremely important part of your diet if you are not fond of other sources of Omega-3 such as salmon and other oily fish.
Sweet potatoes pack more punch in terms of providing Vitamins. They are loaded with Vitamin A and C. They also contain decent amounts of Vitamin E, K and B. These are essential for the maintenance of our mental and physical health. Yams do contain all of these nutrients, but in lesser quantities.
Substitutes for Regular Potatoes
Both yams and sweet potatoes can be used as the perfect replacement for regular potatoes. Even though their texture and taste is a lot different from that of regular potatoes, swapping potatoes with yams can actually improve the flavour profile of your dish.