4 Major Benefits of Sweet Potatoes: Preventing Cancer and Cardiovascular Disease

Sweet potatoes are a healthy and nutritious staple food with a sweet and delicious taste. Research has shown that regular consumption of sweet potatoes can help prevent chronic diseases such as diabetes, cardiovascular disease, and cancer. Additionally, sweet potato leaves also offer various health benefits, including anti-cancer and antioxidant properties.

Sweet potatoes, often referred to as yams, are a highly nutritious food. They contain dietary fiber, vitamins A (beta-carotene), B, and C, as well as trace elements such as iron, magnesium, and potassium. Sweet potatoes also contain a variety of essential amino acids for the human body, hence they are often considered a superfood.

There is growing evidence that sweet potatoes offer at least four major health benefits, as follows:

1. Prevent and Fight Cancer

In a research report published in the Journal of Epidemiology in August 2005, Japanese researchers conducted a follow-up survey of 47,997 men and 66,520 women aged 40 and over for more than seven years. The results showed that regular consumption of sweet potatoes, potatoes, and taro was associated with a decreased risk of kidney cancer death.

A study published in the Journal of the National Cancer Institute in March 1996 found that premenopausal women who consumed vegetables rich in beta-carotene, folic acid, vitamin C, and dietary fiber had a reduced risk of developing breast cancer by approximately 50 percent.

In addition to the aforementioned health benefits, researchers also discovered a unique protein with anticancer activity in sweet potatoes as early as 1931.

A study published in the World Journal of Gastroenterology in June 2013 found that protein purified from sweet potatoes demonstrated significant anti-proliferative and anti-metastatic effects on human colorectal cancer cells both in vitro and in vivo. The proteins not only slowed the growth of colorectal cancer cells but also reduced their migration and invasion.

Additionally, sweet potato leaves have also been shown to have anti-cancer properties. A study published in the Asia Pacific Journal of Clinical Nutrition (APJCN) in 2007 found that consuming vegetables rich in vitamin A, particularly garland chrysanthemum and sweet potato leaves, may provide potential protection from lung cancer.

2. Prevent Cardiovascular Disease

Sweet potato leaves also contain phenolic compounds that can scavenge free radicals, thus reducing vascular inflammation. Therefore, regular consumption of sweet potato leaves by hypertensive patients can effectively prevent the occurrence of cerebral arteriosclerosis.

A study published in Life (Basel) in August 2021 found that consuming sweet potato leaves can lower plasma total cholesterol, low-density lipoprotein, and oxidative stress. The researchers believe that increasing the intake of sweet potato leaves is an effective nutritional strategy for hyperlipidemia and cardiovascular disease prevention. However, the study was conducted with an animal model, so further research is still needed to confirm its effects on the human body.

Dr. Yu Hsiang Fu, former chief physician of the Department of Geriatrics and Gerontology at National Taiwan University Hospital, pointed out in a Facebook post that sweet potatoes are high in dietary fiber, which can lower cholesterol levels. Moreover, sweet potatoes contain mucopolysaccharides that can prevent arteriosclerosis and reduce the risk of heart disease.

Purple sweet potatoes are rich in anthocyanins. A study published in the Journal of Agricultural and Food Chemistry in February 2019 found that dietary intake of anthocyanins has a positive effect on cardiovascular disease prevention. Although the mechanism by which anthocyanins improve cardiovascular health is still unclear, epidemiological data show that people who consume more anthocyanins have a lower risk of dying from myocardial infarction and cardiovascular diseases.

3. Control Blood Sugar Levels

In a 12-week clinical trial published in Diabetes Care in 2004, researchers at the University of Vienna in Austria measured the efficacy of Caiapo, an extract from white sweet potatoes, on metabolic control in 61 patients with Type 2 diabetes. They found that patients taking Caiapo had a significant decrease in their glycated hemoglobin levels from 7.21 to 6.68 percent. The results showed that Caiapo can help reduce plasma glucose and cholesterol levels in patients with Type 2 diabetes.

Another study published in Biological and Pharmaceutical Bulletin in January 2000 found that sweet potatoes have remarkable antidiabetic activity and can improve abnormal glucose and lipid metabolism by reducing insulin resistance.

The researchers fed white-skinned sweet potatoes to mice with diabetes and found that their hyperinsulinemia was significantly improved, with a 60 percent improvement observed after only six weeks of oral administration.

A Facebook post published by Yi Ting Chinese Medicine Clinic in Taiwan stated that 100 grams of sweet potatoes contain only one-third of the calories of the same amount of rice, and their fat and carbohydrate content are also lower than that of rice and noodle. Therefore, consuming sweet potatoes in moderation can help control calorie and fat intake, which may benefit individuals with diabetes.

However, it is important to note that after eating sweet potatoes, the intake of other staple foods should be reduced to control total calorie intake.

According to Fu, sweet potatoes have a moderate glycemic index with a value of around 69. They are also rich in dietary fiber and can create a feeling of fullness, so are less likely to cause fluctuations in blood sugar and insulin, which helps to control blood sugar levels. Fu also advised that to achieve the best effect of controlling blood sugar, sweet potatoes should be consumed without any processing or seasoning.

4. Prevent Constipation

Sweet potatoes are rich in dietary fiber and antioxidants, which help maintain gut health. They contain both soluble and insoluble dietary fiber, which, although cannot be digested and absorbed by the body, provide multiple benefits for the gut.

Soluble fiber, also known as viscous fiber, can absorb water and soften stool, while non-viscous and insoluble fiber does not absorb water but increases stool volume. Both soluble and insoluble fiber can be fermented by bacteria in the colon, producing short-chain fatty acid compounds that serve as nutrients for intestinal wall cells and help maintain gut health.

According to a study published in Cancer Nursing in June 2016, 57 leukemia patients experienced relief from chemotherapy-induced constipation after eating 200 grams of sweet potatoes per day.

Fu mentioned that sweet potatoes can improve gut environment. The dietary fiber in sweet potatoes can promote the growth of probiotics while inhibiting harmful bacteria. This, in turn, increases the number of beneficial bacteria in the gut, leading to a healthier gut and reduced risk of gut problems.