Suha is the Filipino term for pomelo (Citrus maxima), the largest fruit in the citrus family and one of the few ancestral citrus species from which nearly all modern citrus varieties descend. Often compared to grapefruit but considerably sweeter and milder, suha is a staple across Southeast Asia, where it is eaten fresh, juiced, or incorporated into salads and desserts. The fruit’s biology, nutrition, and surprisingly diverse range of uses go well beyond its role as a snack.
A Founding Member of the Citrus Family
Pomelo is not a hybrid. Unlike oranges, lemons, and grapefruits, which are all crosses of two or more ancestral species, pomelo is one of the original parent species of cultivated citrus. Genetic analysis has confirmed that pomelo gave rise to several major citrus varieties, including sweet orange and grapefruit, through ancient hybridization events with other ancestral species like mandarin and citron.1PubMed Central. Diversity of Pummelos (Citrus maxima (Burm.) Merr.) and Grapefruits (Citrus x aurantium var. paradisi) Inferred by Genetic Markers, Essential Oils Composition, and Phenotypical Fruit Traits This makes suha, in a sense, a grandparent of the grapefruit that Western consumers are more familiar with.
The fruit goes by many regional names. In the Philippines it is suha (sometimes spelled “cua” in older texts), in Thailand it is som-o, in China it is yòuzi, and in English-speaking countries it is pomelo, pummelo, or sometimes shaddock (after a 17th-century English sea captain who reportedly brought the fruit to the Caribbean). All of these names refer to the same species, Citrus maxima, though dozens of cultivars exist with different flesh colors, sweetness levels, and peel thicknesses.
What the Flesh Contains Nutritionally
Suha flesh is mostly water, roughly 88 to 90 percent by weight, which makes it refreshing but also means the nutrients it does carry are relatively diluted compared to denser fruits. Across several pomelo varieties studied in Bangladesh, fat and fiber contents were low and did not differ much between cultivars. The carbohydrate content ranged from about 8 to 10 percent, and protein was minimal.2PubMed Central. Exploring the nutraceutical potential: Evaluating the nutritional and bioactive functions of five pomelo fruit varieties in Bangladesh
Where suha earns its nutritional reputation is vitamin C. The same study found vitamin C levels as high as about 80 mg per 100 mL of fresh juice in the highest-performing variety, and even the lowest-performing cultivar still delivered around 64 mg per 100 mL.3PubMed Central. Exploring the nutraceutical potential: Evaluating the nutritional and bioactive functions of five pomelo fruit varieties in Bangladesh A single large suha can easily yield a full day’s recommended vitamin C intake. The fruit also contains meaningful amounts of potassium, calcium, magnesium, and iron, though concentrations vary across cultivars. Carotenoid levels were highest in varieties with pink or red flesh, which is consistent with how pigmentation works across citrus fruits generally.
Flavor, Aroma, and Why Suha Tastes the Way It Does
If you have ever peeled a suha and noticed that it fills the room with fragrance before you even taste it, that is because pomelo peel and flesh are packed with volatile aromatic compounds. Researchers have identified dozens of volatile molecules in pomelo, including aldehydes, alcohols, esters, and terpenes.4PubMed Central. Volatile Composition in Two Pummelo Cultivars (Citrus grandis L. Osbeck) from Different Cultivation Regions in China Terpenes, the same class of compounds responsible for the smell of pine trees and lavender, dominate the aroma profile of suha. The specific mix of these compounds shifts depending on the cultivar and where it was grown, which is why a pink pomelo from Fujian province can smell noticeably different from a white pomelo from Thailand.
Sensory analysis of pomelo juice has found that white-fleshed varieties tend to contain lower total volatiles but higher concentrations of terpenoids, while pink-fleshed varieties lean toward a broader, more complex aromatic profile. Chemical composition correlated strongly with perceived flavor attributes like acidity, freshness, and sweetness.5PubMed. Chemical composition and sensory profile of pomelo (Citrus grandis (L.) Osbeck) juice In practice, this means the variety of suha you buy matters a lot for flavor. A white-fleshed suha tends to taste cleaner and more purely citrusy, while a pink or red one is often sweeter with more complex fruity notes.
The bitterness that some people notice in suha comes from naringin, a flavonoid compound shared with grapefruit. Naringin concentration varies widely among cultivars, and it can be reduced through processing. Researchers have optimized methods for removing naringin from pomelo juice using ion-exchange resins, finding that the process can drop bitterness substantially while retaining most of the juice’s vitamin C content.6PubMed Central. Optimization of debittering and deacidification parameters for Pomelo juice and assessment of juice quality This is mainly relevant for commercial juice production, but it explains why fresh suha eaten out of hand can taste less bitter than bottled pomelo juice that has not been treated.
Flavonoids and Other Bioactive Compounds
Beyond basic vitamins and minerals, suha contains a rich assortment of flavonoids, which are plant compounds that have attracted research attention for their antioxidant and anti-inflammatory properties. The specific flavonoid profile differs dramatically between pomelo cultivars. In some varieties, naringin dominates, while in others, less familiar compounds like melitidin or rhoifolin take the lead.7PubMed Central. The flavonoid profiles in the pulp of different pomelo (Citrus grandis L. Osbeck) and grapefruit (Citrus paradisi Mcfad) cultivars and their in vitro bioactivity This variability means that blanket health claims about “pomelo flavonoids” oversimplify things considerably. The suha on your table may have a completely different bioactive fingerprint from one grown a few hundred kilometers away.
The peel, which most people discard, turns out to be where much of the antioxidant activity concentrates. Essential oil extracted from pomelo peel has shown the ability to reduce oxidative stress markers in cell models. In one study, pomelo peel essential oil reduced reactive oxygen species accumulation and lipid peroxidation in neuronal cells exposed to oxidative damage, with protective effects strongest when the oil was applied before the stress rather than during it.8PubMed Central. Volatile-Driven Antioxidant Activity of Pomelo Peel Essential Oil: Bridging Chemical Composition and Cellular Redox Modulation These are cell-culture results and cannot be directly translated to health claims about eating suha peel, but they point to biological activity worth investigating further.
Even the seeds have generated interest. Oil extracted from pomelo seeds has been studied for potential effects on fat accumulation and oxidative stress in liver cells, with results suggesting it may influence pathways related to lipid storage and antioxidant defenses.9Food Bioscience. Mechanistic studies on the alleviation of lipid accumulation and oxidative stress by Majia pomelo seed oil Again, this is early-stage laboratory work, not evidence that eating suha seeds will do anything specific for your liver. But it suggests the entire fruit, not just the flesh, contains compounds with biological activity.
Metabolic Research and Blood Sugar
A small body of laboratory research has explored how pomelo compounds interact with enzymes and pathways involved in blood sugar regulation and fat metabolism. Extracts from pomelo waste products, including peel and membranes, have been shown to inhibit enzymes that break down carbohydrates and lipids in test-tube settings. Bile acid binding by these extracts may also influence cholesterol absorption.10Current Research in Food Science. Pomelo by-products: A bibliometric review on enhancing gut health and digestive function for metabolic regulation through advanced processing techniques Separately, pomelo waste compounds have been shown to upregulate glucose transport proteins and influence insulin secretion in cell models.11Horticulture, Environment, and Biotechnology. Pomelo fruit wastes are potentially valuable antioxidants, anti-inflammatories, antihypertensives, and antihyperglycemics
It is worth being honest about where this research stands. These findings come from cell lines and test-tube experiments, not from human clinical trials. The jump from “an extract inhibits an enzyme in a petri dish” to “eating suha helps control your blood sugar” is enormous, and most such findings never survive the translation to real-world human health. Suha is a nutritious fruit with plenty of vitamin C and fiber, and that alone is reason enough to eat it. The metabolic research is interesting for scientists working on functional foods, but it should not change how you think about pomelo as part of your diet right now.
The Grapefruit Problem and Drug Interactions
If you take prescription medications, this section matters. Pomelo is closely related to grapefruit, and like grapefruit, it contains furanocoumarins, compounds that inhibit an enzyme in your gut and liver called CYP3A4.12Clinical Dermatology Review. Pomelo Juice–Drug Interactions: A Word of Caution CYP3A4 is responsible for breaking down a wide range of drugs, including some statins, calcium channel blockers, immunosuppressants, and certain anti-anxiety medications. When furanocoumarins block this enzyme, the drug stays in your bloodstream longer and at higher concentrations than intended, which can effectively turn a normal dose into an overdose.
The common misconception is that only grapefruit causes this interaction. Suha can too, because the relevant compounds are present in both fruits. The furanocoumarin content varies between pomelo cultivars and even between individual fruits, so the risk is not perfectly predictable. If your pharmacist has warned you to avoid grapefruit, you should ask about pomelo as well. Some people assume that because suha tastes milder and sweeter than grapefruit, it must be safer in this regard, but taste has nothing to do with furanocoumarin content.
That Remarkably Thick Peel
One of the most distinctive features of suha is its peel, which can be several centimeters thick and makes up a significant fraction of the fruit’s total weight. Structurally, the peel is a foam-like material composed of interconnected cells with large air-filled intercellular spaces. The thickness develops mainly through expansion of existing cells rather than through new cell division, and vascular bundles branch in a regular pattern through the peel tissue at roughly every 16 to 17 percent of the total peel thickness.13PubMed. Structure-function relationship of the foam-like pomelo peel (Citrus maxima)-an inspiration for the development of biomimetic damping materials with high energy dissipation
This structure gives the peel exceptional impact-absorbing properties. A pomelo can fall from a tree at heights of ten meters or more and sustain minimal damage to the flesh inside. Engineers have studied the peel as a model for designing biomimetic damping materials, the kind of shock-absorbing structures used in helmets, packaging, and vehicle safety systems.14PubMed. Structure-function relationship of the foam-like pomelo peel (Citrus maxima)-an inspiration for the development of biomimetic damping materials with high energy dissipation The fact that nature solved the impact-protection problem using interconnected cells with gradually increasing air spaces has provided a template that synthetic materials are still trying to replicate efficiently.
In Southeast Asian cooking, the thick peel is not wasted. It is candied, pickled, or braised in stews. In Chinese cuisine, dried pomelo peel is used in soups and herbal preparations. Filipino households sometimes candy the peel with sugar and dry it as a chewy snack. The albedo, the white spongy layer between the outer rind and the fruit segments, is the part most commonly eaten, since the outermost colored layer (the flavedo) can be quite bitter due to its high essential oil content.
Pectin From the Peel
The food industry has a particular interest in suha peel as a source of pectin, the natural gelling agent used in jams, jellies, and as a thickener in processed foods. Pomelo peel is rich in pectin, and extraction yields can be substantial. Researchers comparing different extraction techniques found that microwave-assisted extraction produced the highest pectin yield at about 20 percent of peel weight, with the resulting pectin showing good viscosity and thermal stability.15PubMed Central. Differences in physicochemical properties of pectin extracted from pomelo peel with different extraction techniques Other methods produced lower yields but different properties. Enzymatic extraction, for instance, yielded less pectin but produced smaller particles with higher antioxidant activity.
The pectin quality also depends on how long the fruit has been stored before processing. Research on a Chinese pomelo cultivar showed that pectin yield dropped from about 39 percent in freshly harvested fruit to around 25 percent after 150 days of storage, as the pectin molecules gradually broke down.16PubMed Central. Physicochemical and Structural Properties of Pomelo Peel Pectin From Majiayou Pomelo With Different Storage Periods This finding has practical implications for the pomelo processing industry: peel destined for pectin extraction needs to be processed relatively quickly after harvest, or the resulting pectin will have lower molecular weight and weaker gelling properties.
Antimicrobial Properties of Peel Oil
Essential oil from pomelo peel has demonstrated antibacterial activity in laboratory settings, with a stronger effect against gram-positive bacteria than gram-negative bacteria. In one study, emulsified pomelo peel oil inhibited Staphylococcus aureus more effectively than Escherichia coli, a pattern consistent with findings for other citrus essential oils.17PubMed Central. Antibacterial Activity of Emulsified Pomelo (Citrus grandis Osbeck) Peel Oil and Water-Soluble Chitosan on Staphylococcus aureus and Escherichia coli The difference likely relates to the structure of bacterial cell walls: gram-negative bacteria have an outer membrane that acts as an additional barrier against hydrophobic compounds like essential oil components.
This research is relevant to food preservation and packaging more than to human medicine. Nobody is suggesting you rub suha peel on a wound. But pomelo peel oil incorporated into food packaging materials or used as a natural preservative in processed foods could potentially reduce bacterial contamination. The idea of replacing synthetic preservatives with plant-derived antimicrobials is a growing area of food science, and citrus peel oils are among the most promising candidates because they are produced in large quantities as waste from juice processing.
Pomelo Peel as an Environmental Cleanup Tool
One of the more surprising applications of suha peel has nothing to do with food. Researchers have converted pomelo peel into biochar, a charcoal-like material produced by heating organic matter in the absence of oxygen, and tested it as an adsorbent for removing heavy metals from contaminated water. Biochar prepared from pomelo peel was able to remove lead from aqueous solutions with a maximum adsorption capacity of about 92 mg per gram at 30 degrees Celsius.18Materials Chemistry and Physics. Adsorption of Pb(II) from aqueous solution by pomelo fruit peel-derived biochar
The appeal of this approach is that it turns agricultural waste into something useful for environmental remediation. In countries where pomelo is commercially processed, enormous quantities of peel are generated with limited uses. Converting that peel into a water-treatment material addresses two problems at once: reducing food waste and providing a low-cost option for cleaning up lead-contaminated water, which remains a serious concern in parts of Southeast Asia and elsewhere. The biochar was prepared using a green synthesis method, meaning it did not require harsh chemicals, which adds to its practical appeal in resource-limited settings.
Growing Suha and Salt Tolerance
Pomelo trees are tropical to subtropical and grow best in warm, humid climates with well-drained soil. In the Philippines, major suha-producing areas include Davao, Mindoro, and parts of the Visayas. The trees are sensitive to salt stress, which is an increasing problem in coastal agricultural zones where seawater intrusion and irrigation with slightly saline water are becoming more common due to climate change.
Research has explored treating pomelo seedlings with salicylic acid and ascorbic acid to improve their tolerance to salt stress, with salicylic acid at a concentration of 300 mg per liter showing the best results across multiple growth indicators.19Al-Furat Journal of Innovations in Agricultural Sciences (FJIAS). Effect of anti-salts in the chemical properties of the pomelo seedlings leaves under salt stress Ascorbic acid at the same concentration also outperformed untreated seedlings. For growers in salt-affected areas, these treatments could help young pomelo trees survive their most vulnerable stage, though the research is still at the seedling level and has not been validated in mature orchards.
Suha trees typically take about eight years to produce a full crop from seed, which is part of why grafted trees propagated from productive mother trees are preferred commercially. Once established, a healthy pomelo tree can produce fruit for decades. The fruiting season in the Philippines generally peaks between September and December, though some cultivars produce fruit year-round in favorable climates. Fruit can weigh anywhere from one to several kilograms, with the largest specimens reaching the size of a basketball, making suha not just the ancestor of most citrus but also, by a comfortable margin, the biggest.