NutriDex

The Supplement Research Compendium
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Guava

Psidium guajava

Tropical vitamin-C powerhouse with soluble fibre

Moderate evidence 🍎Fruits

✚ Updated · How we grade evidence

Evidence tier
Moderate
Research weight
Citations
6 verified / 6
Classification
Fruits
❝
What the evidence says. Several controlled trials; effects real but modest or context-dependent.

Nutrition per serving 1 medium (55 g)

55gSERVING
  • Water 44.4 g82%
  • Sugars 4.9 g9%
  • Fibre 3 g6%
  • Protein 1.4 g3%
  • Fat 0.5 g1%
What's in one serving, by weight — average composition (USDA).
Vitamin C100%+Fibre11%Copper14%Folate7%Potassium5%Vitamin A2%
One serving as % of the adult daily requirement (FDA Daily Values). The bold outer ring = 100% of a day's needs.
37 kcal1.4 g protein3 g fiber0.5 g fat
NutrientPer serving% daily value
Vitamin C125 mg139%
Fibre3 g11%
Copper0.13 mg14%
Folate27 mcg DFE7%
Potassium229 mg5%
Vitamin A17 mcg RAE2%
Magnesium12 mg3%
Calcium10 mg1%

Composition data: USDA FoodData Central ↗

What is Guava?

Guava (Psidium guajava) is a fruit used for exceptionally high vitamin c supports antioxidant and immune function. NutriDex grades the human evidence as Moderate. Guava is among the most vitamin-C-dense fruits, providing roughly 228 mg per 100 g, alongside notable soluble fibre, potassium and (in pink varieties) lycopene. A 12-week single-blind RCT in hypertensive adults reported that high guava intake (around 0.5-1 kg/day before meals) modestly lowered total cholesterol, triglycerides and blood pressure while raising HDL, and a later RCT found favourable lipid and glucose effects when the peel was removed (whereas guava with peel slightly worsened glucose and cholesterol). A double-blind RCT of a guava fruit extract and reviews of guava-leaf preparations show blunting of post-meal glucose spikes, attributed to alpha-glucosidase inhibition by flavonoids. However, the human evidence base is small, often single-blind, geographically narrow and uses impractically large doses, so cardiometabolic claims for ordinary servings remain moderate at best. Most rigorous mechanistic data come from animal and in vitro work rather than large RCTs or meta-analyses. As a whole food, guava is a sound high-fibre, low-energy source of vitamin C and potassium.

Purported Benefits

✓Exceptionally high vitamin C supports antioxidant and immune function
✓Soluble fibre and pectin aid bowel regularity and satiety
✓May modestly lower total cholesterol and triglycerides while raising HDL
✓May reduce blood pressure when substituting for less healthy snacks
✓Blunts postprandial glucose rise (fruit and leaf preparations)
✓Lycopene-rich pink varieties contribute carotenoid antioxidants

Dosing & Compounds

Typical Dose
One to two whole fruits daily (about 55-165 g) as part of a varied diet; older trials used roughly 0.5-1 kg/day before meals to achieve lipid and blood-pressure effects.
Active Compounds
Vitamin C (ascorbic acid)Pectin and soluble dietary fibrePotassiumLycopene (pink-fleshed varieties)Quercetin and flavonol glycosidesPolyphenols and ellagitanninsFolateCarotenoids (beta-carotene)Copper

Safety & Cautions

Generally safe as a food. The hard seeds and high fibre may cause bloating or discomfort in sensitive individuals or those with diverticular disease if eaten in large amounts. As a moderate dietary potassium source, very large intakes warrant caution in advanced kidney disease. Guava-leaf extracts and teas may have additive glucose- and blood-pressure-lowering effects, so people on antidiabetic or antihypertensive drugs should monitor accordingly. Rare allergy (cross-reactivity within latex-fruit syndrome) has been reported. No grapefruit-type CYP3A4 interaction is established for the fruit. Educational only — always check with your doctor or pharmacist before combining Guava with any medicine.

Key Studies

RCT Kumari 2016 ✓ PubMed
RCT (400 g/day, 6 weeks): guava without peel significantly lowered fasting glucose, total cholesterol, triglycerides and LDL, whereas guava with peel slightly raised glucose and cholesterol despite lowering BMI and blood pressure.
RCT Konig 2019 ✓ Full text
Double-blind, placebo-controlled RCT (n=31): a supercritical-CO2 guava fruit extract significantly reduced postprandial glucose at 30 min (p=0.039) and 90 min (p=0.023) versus control.
RCT Singh 1992 ✓ PubMed
Single-blind RCT in 120 hypertensive adults: 12 weeks of guava intake before meals lowered total cholesterol ~9.9%, triglycerides ~7.7% and blood pressure ~9/8 mmHg, and raised HDL ~8%.
Review Thembane 2024 ✓ Full text
Review of preclinical and clinical evidence: guava phytochemicals (quercetin, guaijaverin, kaempferol and others) show anti-hyperglycemic activity via enzyme inhibition and improved glucose uptake, but the authors note the evidence base is dominated by animal and in vitro work.
Review Therapeutic Potential Review 2025 (PMC) ✓ Full text
A 2025 review of guava (Psidium guajava) summarizes human evidence including a 145-participant hypertension RCT showing ~7.9% lower total cholesterol, ~7.0% lower triglycerides and 7.5/8.5 mmHg blood pressure reduction after 4 weeks of guava intake.
Review Deguchi 2010 ✓ PubMed
Review of human and animal data: guava-leaf tea suppresses postprandial blood glucose via alpha-glucosidase inhibition, supporting type 2 diabetes prevention.
6 sources cited · 6 verified Search all studies on PubMed ↗

Common questions about Guava

What is Guava used for?

Guava is most often taken for Exceptionally high vitamin C supports antioxidant and immune function, Soluble fibre and pectin aid bowel regularity and satiety, May modestly lower total cholesterol and triglycerides while raising HDL, May reduce blood pressure when substituting for less healthy snacks. Tropical vitamin-C powerhouse with soluble fibre

Does Guava work — what does the evidence say?

Moderate evidence. Several controlled trials; effects real but modest or context-dependent. Guava is among the most vitamin-C-dense fruits, providing roughly 228 mg per 100 g, alongside notable soluble fibre, potassium and (in pink varieties) lycopene. A 12-week single-blind RCT in hypertensive adults reported that high guava intake (around 0.5-1 kg/day before meals) modestly lowered total cholesterol, triglycerides and blood pressure while raising HDL, and a later RCT found favourable lipid and glucose effects when the peel was removed (whereas guava with peel slightly worsened glucose and cholesterol). A double-blind RCT of a guava fruit extract and reviews of guava-leaf preparations show blunting of post-meal glucose spikes, attributed to alpha-glucosidase inhibition by flavonoids. However, the human evidence base is small, often single-blind, geographically narrow and uses impractically large doses, so cardiometabolic claims for ordinary servings remain moderate at best. Most rigorous mechanistic data come from animal and in vitro work rather than large RCTs or meta-analyses. As a whole food, guava is a sound high-fibre, low-energy source of vitamin C and potassium.

What is the typical dose of Guava?

One to two whole fruits daily (about 55-165 g) as part of a varied diet; older trials used roughly 0.5-1 kg/day before meals to achieve lipid and blood-pressure effects.

Is Guava safe? Any cautions or side effects?

Generally safe as a food. The hard seeds and high fibre may cause bloating or discomfort in sensitive individuals or those with diverticular disease if eaten in large amounts. As a moderate dietary potassium source, very large intakes warrant caution in advanced kidney disease. Guava-leaf extracts and teas may have additive glucose- and blood-pressure-lowering effects, so people on antidiabetic or antihypertensive drugs should monitor accordingly. Rare allergy (cross-reactivity within latex-fruit syndrome) has been reported. No grapefruit-type CYP3A4 interaction is established for the fruit.

How many studies support Guava?

NutriDex cites 6 sources for Guava, graded "Moderate".

Cite this page
APA

Peh, D. (2026). Guava (Psidium guajava): Benefits, Dosage, Side Effects & Evidence. NutriDex — The Supplement Research Compendium. Retrieved 26 Jun 2026, from https://nutridex.info/s/guava

BibTeX
@misc{nutridex_guava,
  author       = {Peh, Daryl},
  title        = {Guava (Psidium guajava): Benefits, Dosage, Side Effects \& Evidence},
  year         = {2026},
  howpublished = {NutriDex --- The Supplement Research Compendium},
  url          = {https://nutridex.info/s/guava},
  note         = {Reviewed by Dr Daryl Peh, MBBS Singapore, MMed FM. Accessed 2026-06-26}
}

For medical claims, citing the underlying primary studies linked above is preferred. NutriDex is an educational reference, not medical advice.

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