Jicama: eaten raw, and barely studied

Jicama is eaten raw, and that is the most interesting thing anyone has measured about it. Laboratory work on two varieties put the estimated glycemic index of the root between 20.1 and 22.2, well under the 55 that counts as low, and the reason offered is that raw starch reaches digestion in its native granular form, which enzymes struggle to attack. Hold both findings loosely. They come from digestion in a tube rather than from people eating anything, and nobody has measured what cooking does. The strong evidence on this page is not about jicama. Two meta-analyses, one pooling 55 randomised trials in 2518 adults and one pooling 11 trials in 634 people with type 2 diabetes, tested inulin-type fructans given as supplements. What was tested was a purified supplement, not food. Nothing we hold measures inulin or fructans in jicama root, and neither meta-analysis card carries the dose people swallowed, so there is no way from those numbers to a plate of raw vegetable. We also hold no USDA entry for jicama in this cohort, so there is no nutrient table below to check any of this against.

How much is actually in it

• In two jicama varieties followed through root development, starch was the main carbohydrate of the dry solids and soluble fibre stayed under 10%, peaking at 4.72% and 6.56%. — two jicama materials, yellow seed and purple seed, sampled at 106 to 190 days of growth (n = 2 varieties) Evidence D source
  Soluble fibre peaks 4.72 +/- 0.10% at 160 days and 6.56 +/- 0.22% at 190 days of dry base; starch 31.4% to 43.7%
• The same laboratory work put the estimated glycemic index of jicama root between 20.1 and 22.2, which is low on the usual cut-off of 55. — jicama roots of two varieties digested in vitro at several growth stages (n = 2 varieties) Evidence D source
  Estimated GI 22.2 at 106 days falling to 20.1 at 190 days

What your body absorbs

• Because jicama is eaten raw, its starch reaches digestion in the native granular form, which laboratory work describes as less susceptible to enzyme attack. No glycemic response was measured in people. — jicama root starch, laboratory digestion and cited starch chemistry Evidence D source
  Native starch less susceptible to enzymatic action, no cooked comparison measured

What it does to your health

• In a 20-person crossover trial, baked jicama chips acted as the low fat, low sodium, low carbohydrate negative control in a snack preference test and were rated lower on liking, wanting and craving than regular potato chips (p = .011 to .0001). — 20 adults in a laboratory, four sessions, within-subjects double-blind crossover (n = 20) Evidence B source
  Full-dose potato chips rated higher on liking, wanting, craving and willingness to eat again, with lower demand elasticity and higher break point (p < .0001)
• Supplements of isolated inulin-type fructans lowered LDL cholesterol by 0.14 mmol/L and body weight by 0.97 kg across 55 randomised trials in 2518 adults. — 2518 adults in 55 randomised trials of at least 2 weeks, given isolated fructan supplements rather than jicama (n = 2518) Evidence A source
  LDL-C -0.14 mmol/L (95% CI -0.24 to -0.05), triglycerides -0.06 mmol/L, body weight -0.97 kg (95% CI -1.28 to -0.66)
• Supplements of inulin-type carbohydrates lowered fasting glucose, fasting insulin, HbA1c and HOMA-IR in 11 pooled trials covering 634 people with type 2 diabetes, while body mass index did not move (P = 0.08). — 634 adults with type 2 diabetes in 11 meta-analysed trials of isolated inulin supplements, plus 14 trials reviewed narratively (n = 634) Evidence A source
  Significant reduction in fasting plasma glucose, fasting insulin, HbA1c and HOMA-IR, no change in BMI (P = 0.08)

Safety, limits and interactions

• Five people in Taiwan were poisoned by soup made from yam bean seeds, the part of the jicama plant that is not food, and one lost consciousness with severe metabolic acidosis. — five adults in southern Taiwan who shared one soup made from yam bean seeds (n = 5) Evidence C source
  Perioral numbness, nausea and vomiting in all five, coma and lactate 185 mg/dL in one 54-year-old woman, all recovered

The bottom line

The one hard safety fact here is about the part you do not eat. Five adults in southern Taiwan shared a soup made from yam bean seeds, the seed of the jicama plant, and all five had numbness around the mouth, nausea and vomiting. One woman of 54 lost consciousness with severe metabolic acidosis and a lactate of 185 mg/dL. All five recovered. Buy the root, and leave the seeds alone: they are not food. What we hold on the root itself is thin. Two varieties were followed through root development, and starch was the main carbohydrate of the dry solids at 31.4 to 43.7 percent, while soluble fibre stayed under 10 percent, peaking at 4.72 percent at 160 days of growth and 6.56 percent at 190 days. That is plant science on two seed types, measured to answer a question about growing the crop. Jicama also turns up in one human trial by accident. Baked jicama chips were the low fat, low sodium, low carbohydrate control against potato chips in 20 adults, and people rated them lower on liking, on wanting and on craving, with p values between .011 and .0001. Take that as a sober result about how a bland snack competes for your attention. It says nothing about health either way. Now the gaps, because they are larger than what is above them. We have nothing on what cooking does to jicama, nothing on what a realistic portion looks like across a day of eating, and nothing on who should treat it differently. Pregnancy, children, older people, kidney disease and interactions with medicines are all blank for this root. Our safety evidence covers seed poisoning and stops there, so the honest answer about the root is that nobody has studied who it might not suit. If you are managing a condition or taking medication, that question belongs with the person treating you, and this page cannot stand in for them.

Sources

1. jic-daily-r2-01 · food composition study
   Soluble fiber (Figure 4c) content increased during root growth, peaking at 160 days of development for YS (4.72% ± 0.10%) and at 190 for PS (6.56% ± 0.22% YS). ... From these results, it is clear that the main carbohydrate in jicama solids is starch, followed by fiber, where soluble fiber represents less than 10%.
   Food Science & Nutrition, 2022 · checked 2026-09-23
2. jic-daily-r2-02 · in vitro study
   The yellow seed variant showed a statistically significant difference (p <.05) during the maturation times, where the highest value was observed at 106 days (eGI = 22.2), with a tendency to decrease through development stages (190 days, IG = 20.1). ... Based on our results, jicama can be classified as a low glycemic index (GI) food, taking into consideration the Atkinson et al. (2008) GI classification report, which cites that those foods with GI values lower than or equal to 55 are classified as low.
   Food Science & Nutrition, 2022 · checked 2026-09-23
3. jic-daily-r2-03 · in vitro study
   In other works, Bertolini (2010) and Douzals et al. (1996) cited that the native starch is less susceptible to the enzymatic action, and since jicama is mostly consumed as a raw product, its starch remains in its native form, even during the digestion process.
   Food Science & Nutrition, 2022 · checked 2026-09-23
4. jic-daily-r2-05 · randomised controlled trial
   Food stimuli consisted of regular potato chips; a negative control low in fat, sodium, and carbohydrates (Jicama vegetable chip, baked); and modified-dose potato chips (either no fat or no sodium). ... Full-dose chips were rated significantly higher on liking, wanting, craving, and willingness to eat again, versus negative control (p = .011-.0001).
   Exp Clin Psychopharmacol, 2026 · checked 2026-09-23
5. jic-daily-r2-06 · systematic review and meta-analysis
   The pooled estimate showed that ITF supplementation reduced LDL-C [mean difference (MD) -0.14 mmol/L, 95% confidence interval (95% CI: -0.24, -0.05), 38 RCTs, 1879 participants, very low CoE], triglycerides (MD -0.06 mmol/L, 95% CI: -0.12, -0.01, 40 RCTs, 1732 participants, low CoE), and body weight (MD -0.97 kg, 95% CI: -1.28, -0.66, 36 RCTs, 1672 participants, low CoE) but little to no significant effect on other cardiovascular disease risk factors.
   Am J Clin Nutr, 2024 · checked 2026-09-23
6. jic-daily-r2-07 · systematic review and meta-analysis
   Our results did not find ITC supplementation decrease postintervention and reduction data of BMI (P = 0.08). However, it can significantly decrease postintervention and reduction data of FPG, FI, HbA1c, and HOMA-IR.
   J Diabetes Res, 2019 · checked 2026-09-23
7. jic-daily-r2-04 · case series
   The five patients presented with perioral numbness, nausea and vomiting after eating a same soup made from yam bean seeds. One of them, a 54-year-old woman, had difficulty breathing and lost consciousness.
   Intern Med J, 2007 · checked 2026-09-23