The use of yam to treat fertility issues like uterine and ovarian spasms, menstrual cramps, and dysmenorrhea, balance estrogen levels, and improve the quality and quantity of cervical mucus dates back to the 18th and 19th centuries .
Research shows that yam, a Dioscorea species  contains a plant-based estrogen called Diosgenin which can be chemically converted into phytoestrogen . However, research suggests our body cannot diosgenin convert into phytoestrogen, except in the lab.
Regarding the link between yam, fertility, and twining, research by Ugwonali a student at the University of Yale, according to his findings suggests that a chemical in yam acts as anti-estrogen, which fools the brain into thinking there is insufficient estrogen, causing it to release more of a hormone called gonadotrophin and increase the ovulation rate in female.
The big question is, Is yam good for someone trying to conceive? Yes. Research suggests it can stimulate the secretion of the follicle-stimulating hormone (FSH) which makes the ovaries release mature eggs.
This article provides evidence-based insights into the incredible benefits of yam for fertility, bioactive compounds, nutritional value, how to eat, and some possible concerns. Grab a cup of tea and let us delve into the world of Dioscorea species (yam).
Yam contains several other bioactive  compounds such as:
- Steroidal Saponins
These compound found in yam also has several therapeutic uses. In traditional herbal medicine, it is used for the treatment of several health conditions .
After the discovery of diosgenin in yam by scientists in the 1950s, Yam became a highly sought-after plant. For instance, in the pharmaceutical industry, yam is in high demand for preparing steroids. Most sought-after in the cosmetic industry due to its safe use in cosmetic formulations .
FUN FACTS Even the great University Of Bath, a leading university in the UK with an international reputation for excellence in teaching and research, spent 10 years in research and development of a species of fenugreek that can produce large amounts of diosgenin.
Yam Nutrient profile
According United States Department of Agriculture, 100 grams of raw yam contains the following major nutrients in percentage(%) of their Required Daily Intake (RDI).
- Carbohydrate 14%
- Fiber 16%
- Calcium 2%
- Iron 3%
- Magnesium 5%
- Phosphorus 8%
- Potassium 22%
- Zinc 3%
- Copper 9%
- Manganese 17%
- Selenium 10%
- Vitamin C 28%
- Thiamin 8%
- Riboflavin 2%
- Niacin 35%
- Pantothenic acid 16%
- Vitamin B-6 15%
- Folate 6%
- Choline 3%
- Carotene 6%
- Vitamin A 15%
- Vitamin E 23%
- Vitamin K 58%
- Arginine 2%
- Aspartic acid 2%
- Glutamic acid 2%
Other micronutrients are in their small amount found in Dioscorea species .
FUN FACTS According to 2018 statistics on the Global distribution of yam production Africa is the highest with 96.2%, followed by America 2.0%, Caribbean 1.0%, Oceania 0.6%, Asia 0.2%, and Europe 0%. Whereas in Africa, Nigeria is the highest yam-producing country with 65.9%, followed by Ghana with 10.7%, Côte d’Ivoire with 9.9%, and other countries combined to have 14.5% [10, 11].
Benefits of Yam for Fertility
A species of yam popularly called wild yam has been traditionally used to promote fertility due to its purported ability to balance hormones and improve the quality of cervical mucus. However, after due research on possible ways yam can influence fertility, here are some benefits of yam for fertility and studies backing them up.
1. Boost Ovulation in women
What yam stimulates ovary production? wild yam. A study on postmenopausal women who had two-thirds of their staple food replaced with yam for 30 days had increased serum estrogen levels which led to a significant increase in serum estrone and estradiol concentrations, both of which are essential for maintaining reproductive health in women .
This suggests that regular intake of yam-based diets can influence fertility positively, possibly because estrogen plays a crucial role in regulating the menstrual cycle, stimulating ovulation, and supporting the endometrial lining, all of which are critical for fertility.
2. Improves Sex Hormone Balance
In a study comparing two groups of menopausal women, group 1 ate 390 grams daily for 30 days while group 2 ate 240 grams of sweet potato daily for 41 days .
The result revealed that those who ate yam had a decreased free androgen index (FAI), which is a measure of the ratio of free testosterone to SHBG. A high FAI can indicate androgen excess, which can disrupt ovulation and fertility. The observed decrease in FAI suggests that yam consumption may help balance sex hormones, potentially improving fertility outcomes.
3. May help lower inflammation
Study shows that acute inflammation can affect ovulation and hormone production, and may cause endometriosis which is detrimental to fertility .
4. May relieve Menopausal Symptoms
Yams may offer some relief from the symptoms associated with menopause.
According to a study involving 24 postmenopausal women, it was found that substituting rice with yams for two out of three meals daily over 30 days resulted in a 26% and 27% increase in blood levels of estrone and estradiol, respectively .
However, a separate six-month study revealed that topical application of wild yam cream had minimal effect on menopause symptoms, such as hot flashes and night sweats, compared to a placebo .
Additionally, a cream made from wild yam root extract can be used as a safe alternative therapy to alleviate menopause symptoms like hot flashes and night sweats .
It’s important to note that more in-depth research is needed to understand the potential role of yams in managing menopause symptoms.
5. Reduces uterine cramping
According to anecdotal evidence, wild yam a species of yam possess an antispasmodic effect and may help uterine cramping – a condition that occurs during menstruation when the uterus contract to expel its lining .
There is also a claim that wild yam may help treat nausea and vomiting during pregnancy . However, there is a lack of scientific evidence to support these uses.
6. Improves Lipid Profile and Antioxidant Status
Yam consumption also led to a significant decrease in plasma cholesterol concentration and a prolongation of the lag time of LDL oxidation .
These changes indicate improved lipid profiles, which are beneficial for overall cardiovascular health.
Additionally, the observed decrease in urinary isoprostane levels suggests an enhancement of antioxidant status, which may protect against oxidative stress and promote cellular health, including reproductive cells [33, 34, 35].
7. Reduces Genotoxic Metabolite of Estrogen
The study found a significant decrease in urinary 16alpha-hydroxyestrone, a genotoxic metabolite of estrogen. This metabolite is linked to an increased risk of breast cancer, and its reduction suggests that yam consumption may have protective effects against breast cancer [36, 37, 38, 39].
Another piece of evidence is based on a test tube study where peeled Chinese yam was used, Indications shows antitumor and antioxidant effect . However, a study on humans is needed to confirm if it has the same effects in humans.
While the exact mechanism behind yam’s potential fertility-enhancing effects is not fully understood, the article provides compelling evidence that yam consumption may have positive implications for reproductive health in postmenopausal women.
However, further research is warranted to investigate the long-term effects of yam consumption on fertility and overall health in women of all ages.
How to Eat Yam
Yam can be eaten in a variety of ways. It can be:
- Added to soups, stews, and stir-fries.
Benefits of Yam During Pregnancy
Yam provides a moderate amount of Fiber, Calcium, Iron Copper, Selenium, vitamins A, C, and E, B-complex, and Folate which help prevent various pregnancy-related health problems and aid in healthy fetal development.
Also, yam is generally considered safe for consumption during pregnancy. Additionally, Some studies suggest that species like wild yam may help to reduce morning sickness and ease pregnancy-related discomfort.
Downsides of Yam
Wild yam is generally considered safe for most people. However, certain varieties like wild yam may interact with certain medications, such as oral contraceptives and hormone replacement therapy. It is important to talk to your doctor before taking wild yam if you are taking any medications.
History of Yam Use
Wild yam has been used in traditional medicine for centuries. It has been used to treat a variety of ailments, including infertility, menstrual problems, and menopause.
Yam is a safe and natural food that may offer some benefits for fertility and pregnancy. However, further research is still needed to clear the doubt surrounding its estrogenic activities, as well as to understand its mechanism of action.
JC is passionate about finding the impact of foods (feeding habits) on human fertility and reproductive health and a way to improve fertility.