Know2eat

Yam

Dioscorea spp.

What yam has been studied for

2 associations assessed — none with dependable human evidence behind them yet. Strongest first.

  • 2 Insufficient
3 things to know first — allergies, interactions and intake limits

About yam

A large starchy tuber from climbing vines of the genus Dioscorea, staple across West Africa, the Caribbean and parts of Asia. It is a different plant from the sweet potato, despite the American use of the word.

Also known as True yam, Igname, Nagaimo (Chinese yam), Ube (purple yam)

Blood Sugar & Metabolic HealthWomen's Health

The evidence in depth

Best supported: Insufficient

What each association actually rests on, and the papers behind it. A rating describes the state of the research, not how impressive the food is. How we rate evidence.

Blood glucose response

Blood Sugar & Metabolic Health
Insufficient evidence

Yam is often described as a slow-release carbohydrate. Measured glucose responses vary widely between species and cooking methods, and the human data are too sparse and too inconsistent to support the claim.

Insufficient evidence. Not enough human research to say anything useful yet.

1 source

Deep research mode adds each paper’s own conclusion and stated limitations.

Menopausal symptoms

Women's Health
Insufficient evidence

Wild yam is one of the most heavily marketed natural products for hot flushes. The few controlled trials of wild yam cream found no difference from placebo, and there is no evidence that eating the food vegetable affects menopausal symptoms.

Insufficient evidence. Not enough human research to say anything useful yet.

2 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Ask about Yam

Ask about Yam

Answers are written only from the entries on this page — the same nutrients, compounds, claims and citations you can read above. Nothing is added from outside the database, and every answer lists what it was built from.

AI explanations are not switched on for this site, so there is nothing to ask here. Everything above is read straight from the database and does not need them.

Key nutrients

Nutrient content per 100 grams
NutrientAmount% DV
Macronutrients
Calories118 kcal6%
Protein1.53 g3%
Total fat0.17 g0%
Carbohydrate27.9 g10%
Fibre4.1 g15%
Total sugars0.5 g—
Water69.6 g—
Fats
Saturated fat0.037 g0%
Monounsaturated fat0.0060 g—
Polyunsaturated fat0.076 g—
Cholesterol0 mg0%
EPA (omega-3)0 g—
DHA (omega-3)0 g—
DPA (omega-3)0 g—
Linoleic acid (omega-6)0.064 g—
Vitamins
Vitamin A7 µg1%
Vitamin C17.1 mg19%
Vitamin D0 µg0%
Vitamin E0.35 mg2%
Vitamin K2.3 µg2%
Thiamin (B1)0.112 mg9%
Riboflavin (B2)0.032 mg2%
Niacin (B3)0.552 mg3%
Pantothenic acid (B5)0.314 mg6%
Vitamin B60.293 mg17%
Folate23 µg6%
Vitamin B120 µg0%
Choline16.5 mg3%
Minerals
Calcium17 mg1%
Iron0.54 mg3%
Magnesium21 mg5%
Phosphorus55 mg4%
Potassium816 mg17%
Sodium9 mg0%
Zinc0.24 mg2%
Copper0.178 mg20%
Manganese0.397 mg17%
Selenium0.7 µg1%
Other measured compounds
Beta-carotene83 µg—
Alpha-carotene0 µg—
Lycopene0 µg—
Lutein + zeaxanthin0 µg—
Caffeine0 mg—
Ash0.82 g—

Nutrient values are per 100 g of the USDA reference entry named on this page and vary with variety, growing conditions, storage and preparation.

Source record: Yam, raw (USDA FoodData Central, FDC ID 170071).

% DV uses the FDA Daily Values for adults and children aged 4 and over. A dash means no Daily Value has been established for that nutrient.

Bioactive compounds

Compounds present in meaningful amounts. Presence is banded rather than quantified, because whole-food levels vary enormously with variety, growing conditions, storage and preparation.

How preparation changes things

Only effects with real support are listed. If a preparation method is missing, it is because nothing dependable is documented — not because it makes no difference.

  • boiledReduces irritant compounds

    Boiling with the water discarded is the standard preparation and removes the water-soluble irritants that make the raw tuber unpalatable.

Things to know

Allergies, interactions and intake concerns. Every food gets this section — a reference where everything is uniformly good is not a reference.

  • Worth knowing

    Wild yam does not become progesterone in the body

    Wild yam creams and capsules are sold on the premise that their diosgenin converts to progesterone. That conversion is an industrial chemical process and does not happen in human physiology. Products that have produced hormonal effects in testing generally turned out to contain added synthetic hormone.

  • Worth knowing

    Raw yam is not edible

    Most Dioscorea species contain irritant compounds and, in some wild species, alkaloids such as dioscorine that require prolonged soaking or boiling. Cultivated yam must be cooked; handling the raw peeled tuber causes itching for many people.

  • Worth knowing

    Naming confusion with sweet potato

    Orange-fleshed sweet potatoes are labelled yams in much of the United States. They are a different species with a very different nutrient profile, and the USDA record behind this page is a true yam.