Yam Calories & Nutrition Calculator

Raw yam has 118 kcal per 100g with an extraordinary 816mg potassium (17% DV) — the highest potassium density among common starchy tubers. Sweet potato has 337mg, potato has 425mg, and taro has 591mg per 100g. Banana — the food most associated with potassium — has just 358mg. Yam delivers 2.3 times banana's potassium per 100g, though at 33% more calories (118 vs 89 kcal) ^[1][2].

One cup of cubed raw yam (150g) provides 1,224mg potassium — 26% of the daily value — in 177 kcal. This exceeds a large banana's potassium (~422mg) by nearly three times. A 200g cooked yam portion delivers 1,340mg potassium (29% DV) at 232 kcal. Even after boiling, which leaches 18% of the potassium into cooking water, yam retains 670mg per 100g — still 87% more than banana ^[1].

For food journaling, if tracking potassium intake, yam is among the most concentrated whole-food sources available. The potassium-per-calorie ratio is 6.92 mg/kcal — better than banana (4.02), potato (5.52), and sweet potato (3.92). Only spinach (24.3) and radish (14.6) substantially exceed it among common foods.

Yam has 27.88g total carbohydrates per 100g, of which only 0.50g is sugar — meaning 98.2% of its carbohydrate is complex starch and dietary fiber. This is in stark contrast to fruits like banana (12.2g sugar out of 22.8g carbs = 54% sugar), apple (10.4g sugar out of 13.8g carbs = 75% sugar), and even sweet potato (4.2g sugar out of 20.1g carbs = 21% sugar) ^[1][3].

The starch in yam is primarily amylose-rich, which influences its texture — yam becomes firm and slightly waxy when cooked rather than fluffy like potato. One cup of cubed raw yam (150g) provides 41.8g carbohydrates with just 0.75g sugar and 6.2g fiber (22% DV). The carb-to-fiber ratio of 6.8:1 is more favorable than white rice (60:1), potato (8.3:1), and comparable to sweet potato (6.7:1) ^[2].

For food journaling, yam should be tracked as a starchy vegetable with a uniquely low sugar contribution. A 100g serving provides about 2g more carbs than sweet potato (27.9 vs 20.1g) but with 88% less sugar (0.5 vs 4.2g). The slow-digesting starch profile means the calorie release pattern differs fundamentally from fruit or refined carbohydrate sources.

Raw yam provides 17.1mg vitamin C per 100g (19% DV) — less than potato (19.7mg) and far below broccoli (89mg raw / 65mg boiled), but substantially more than sweet potato's 2.4mg and taro's 4.5mg. Among starchy root vegetables specifically, yam's vitamin C ranks second only to potato. Boiling reduces it to 12.1mg per 100g — a 29% loss, consistent with the 25–35% vitamin C reduction seen in most boiled root vegetables ^[1][4].

The vitamin C efficiency is 0.14mg per calorie raw — lower than strawberry (1.84) or orange (1.13), but notable for a starchy root vegetable that most people eat for its carbohydrate rather than its vitamin content. One cup of raw yam (150g) provides 25.7mg vitamin C (29% DV); boiled, this drops to 18.2mg (20% DV) ^[1].

For food journaling, if tracking vitamin C alongside carbohydrates, yam offers a meaningful but not exceptional contribution. The cooking loss is moderate: steaming preserves more vitamin C than boiling (roughly 15–20% loss vs 29%), so preparation method matters for precise logging.

Yam provides 4.1g dietary fiber per 100g (15% DV) — identical to taro (4.1g), 37% more than sweet potato (3.0g), and nearly double potato's 2.1g. Among starchy staples, only lotus root (4.9g) exceeds yam in the root vegetable category. The fiber is predominantly insoluble, contributing to the firm texture of cooked yam ^[1][2].

One cup of cubed raw yam (150g) delivers 6.2g fiber (22% DV) — equivalent to 2.5 cups of cooked white rice (0.4g fiber per 100g) or a large pear (5.5g). After boiling, fiber drops slightly to 3.9g per 100g (14% DV), a 5% reduction mostly due to water absorption changing the weight ratio ^[1].

For nutrition journaling, yam is a high-fiber starchy option. If comparing root vegetables for fiber content: yam and taro tie at 4.1g, sweet potato follows at 3.0g, potato at 2.1g, and cassava at 1.8g per 100g. Pairing yam with other high-fiber foods easily reaches the 28g DV target.

Yam tubers contain diosgenin — a steroidal saponin concentrated in the peel and outer layers — at levels varying from 0.02% to 3.5% of dry weight depending on species and variety. Dioscorea villosa (wild yam) and D. zingiberensis have the highest diosgenin concentrations, while common food yams (D. alata, D. rotundata) have lower levels. Diosgenin is a steroid precursor used industrially but is not a nutrient tracked in food databases ^[2][3].

Dioscorin is a storage protein unique to yam tubers, constituting approximately 80–85% of the total soluble protein in some species. It has documented enzymatic properties (trypsin inhibitor activity, carbonic anhydrase activity) that distinguish it from typical plant storage proteins. Allantoin, a nitrogen-rich compound found in yam mucilage at 0.01–0.02% of fresh weight, is another compound absent from standard nutrition panels ^[2][4].

For food journaling, standard calorie and macronutrient tracking will not capture diosgenin, dioscorin, or allantoin. If logging phytonutrient diversity, note that yam belongs to a distinct botanical family (Dioscoreaceae) with a unique bioactive profile not shared by potato, sweet potato, or taro — which are all from different plant families.