Bromelain 5000 GDU: complete guide, false myths and gastroresistance

Bromelain is a complex of proteolytic enzymes extracted from the stem of the pineapple (Ananas comosus). In supplements, it is used to support digestive function and to promote the drainage of body fluids — the classic heavy-leg feeling — along with the functionality of the microcirculation. However, the '5000 GDU bromelain' products on the market are not all equivalent. They are distinguished by three technical factors: the enzymatic activity delivered per daily dose, the choice between capsule and tablet form, and protection from gastric acidity.

What is bromelain and why is it used

The name bromelain refers to a mixture of enzymes, predominantly endopeptidases from the cysteine protease family, extracted from the stem and fruit of the pineapple. Its main activity is proteolysis, which is the ability to break the bonds that hold proteins together and break them down into smaller, more absorbable fragments.

People who take it generally do so for two reasons.

As a digestive support. Taken with meals, bromelain works in the digestive tract as an aid to the digestion of dietary proteins. This is its oldest use, and it is one of the physiological effects of pineapple recognised by the Ministry of Health guidelines. For the same reason, it is often sought by those who follow high-protein diets.

For drainage and microcirculation. Taken away from meals, bromelain is absorbed in the intestine in its active form. The physiological effects indicated by the ministerial guidelines for pineapple (stem and fruit) include the drainage of body fluids, the functionality of the microcirculation and counteracting the imperfections of cellulite.

Alongside these two practical reasons, there is the field of research. A systematic review published in Nutrients in 2024 summarises decades of studies on the mechanisms of action of bromelain (Kansakar et al., 2024). These range from fibrinolytic activity — the ability to degrade fibrin, a protein involved in the stagnation of fluids in tissues — to the modulation of mediators such as cytokines and prostaglandins. These are areas of study that describe the biological mechanisms of the extract.

What does GDU mean? The unit that measures quality

One of the most common mistakes when choosing an enzyme supplement is to evaluate it by its milligrams. The weight only tells you how much powder is in the capsule; it says nothing about how much that powder works. The unit that measures an enzyme's potency is the GDU (Gelatin Digesting Units), which indicates how much gelatin the enzyme can digest under standardised laboratory conditions.

Therefore, two products both declaring "500 mg of bromelain" can have radically different biological activity, if the raw material of the first is standardised to 1200 GDU/g and that of the second to 5000 GDU/g. The most widespread false myth in this category is built on this ambiguity.

The 'false 5000 GDU' trick

The wording "5000 GDU Bromelain" printed in large letters on the front of a package can refer to two distinctly different concepts:

1. the standardisation of the raw material — one gram of that bromelain has an activity of 5000 GDU;
2. the actual activity delivered by the daily dose — how many GDUs you really take with the capsules specified in the dosage instructions.

1

• Bromelain standardised to 5000 GDU/g (full capsule)

2

• Diluted with fillers (capsule with mixed granules)

The market shortcut works like this. A raw material standardised to 5000 GDU/g is purchased and minimal doses are inserted into the formula, for example 100 mg per capsule, equivalent to just 500 actual GDUs. The rest is filled with cheap bulking agents, and '5000 GDU' is still emblazoned on the label. The product quotes 5000 GDU, but delivers a fraction of it.

The first check is in the list of ingredients, where the standardisation must appear clearly, for example "bromelain 5000 GDU/g". In the same list, you should check that there are not multiple bromelains with different standardisations mixed in the same formula, a typical sign of dilution with lower grades. The second check is the table of average contents, which states how much bromelain and how much enzymatic activity correspond to the daily dose.

Our label declares everything. The raw material is bromelain from pineapple stem, standardised to 5000 GDU/g. Each capsule contains 180 mg, which is equivalent to 900 GDU. The daily dose of 3 capsules provides 540 mg, for a total activity of 2700 actual GDU. You can find all the values on the product page for gastro-resistant Bromelain 5000 GDU.

How much bromelain is needed? What the studies say

To assess whether a dose makes sense, the reference is the scientific literature. According to the systematic review by Kansakar and colleagues (Nutrients, 2024), studies on bromelain have used daily oral doses ranging from 160 mg up to 2000 mg, with frequent protocols in the 750–1000 mg/die range. The same review reports a favourable safety profile, even for prolonged intake.

The daily dose of our Bromelain 5000 GDU is 540 mg of high-titration extract, equivalent to 2700 GDU, and falls squarely within the documented range. When comparing products, GDU count more than milligrams. 540 mg of bromelain standardised to 5000 GDU/g provides a higher enzymatic activity than higher ponderal doses of less concentrated extracts.

Capsules or tablets? Why for an enzyme the difference is huge

Most of the 5000 GDU bromelain products on the market are sold in tablets. For a mineral or a thermostable vitamin, a tablet is a perfectly valid and efficient choice. For an enzyme, the picture changes. To produce a tablet, the powder must be compacted under pressure, and this compression generates mechanical friction and heat.

Enzymatic activity depends on the protein's three-dimensional structure, and the shear forces of compaction can degrade it. Pharmaceutical technology studies have documented this for enzymes, including papain—a cysteine protease from the same family as bromelain—where compression produced increasing losses of activity as the applied forces increased (Sharma et al., 2014; Kuny & Leuenberger, 2003).

NUTRALAB has therefore chosen capsules. The powder is gently dosed into the casing without compaction or mechanical or thermal stress, and the activity of 900 GDU per capsule remains as declared.

This applies to enzymes. For other ingredients, the tablet remains the right form, and we have explained the criterion for choosing between the two in capsules or tablets: how the form of a supplement is chosen.

Bromelain, a delicate enzyme: from production to the jar

The quality of a bromelain product is also decided during production, even before the formula. Bromelain is a delicate active ingredient that degrades on contact with light and air. This is why, in NUTRALAB's production, all the procedures required for sensitive active ingredients are applied. Exposure to light and air is controlled throughout the entire process, from the raw material to the packaging.

It's a three-link chain of protection that continues even after production:

1. during processing — procedures for delicate active ingredients, against light and air;
2. in the gastro-resistant capsule — against gastric acidity;
3. in the dark glass jar — against light and moisture, for the entire life of the product.

Gastro-resistance: the enzyme's journey to the intestine

Enzymes are proteins, and proteins are affected by the environment they are in. Bromelain's activity is documented within a pH window of between 3 and 7 (Kansakar et al., 2024). The empty stomach operates at a pH of 1.5–2, which is outside that window.

1

• Stomach (pH 1.5–2): capsule intact

2

• Intestine (pH 6.8–7.2): enzyme released

A traditional capsule dissolves in the stomach in a few minutes, exposing the enzyme to the most hostile environment in the digestive tract. Our capsule, on the other hand, uses a gastro-resistant vegetable shell made of hydroxypropyl methylcellulose (HPMC, E 464) and gellan gum (E 418). It remains intact in the acidic environment of the stomach. It breaks down in the small intestine, where the pH rises towards neutrality, within the enzyme's window of activity and at the site where absorption occurs.

Clean excipients: free from magnesium stearate and silicon dioxide

Alongside the active ingredient, a supplement's label often lists technical excipients. Two of the most common are magnesium stearate (a processing lubricant) and silicon dioxide (an anti-caking agent, E 551, typically in nanoparticle form). They are legal and very common. NUTRALAB has chosen not to use them.

In their place, this formula uses two solutions of natural origin: L-leucine, an amino acid with an anti-caking function, and silica from young bamboo stem extract, a plant-based alternative to synthetic silicon dioxide. We explain what excipients do in Excipients in supplements: what they do and which ones matter, along with EFSA's assessments, studies on magnesium stearate and E 551, and the criteria by which we chose ours. If you want to learn more about how to evaluate a formula, we have written a guide on how to choose a quality supplement.

A useful note for reading labels: titanium dioxide (E171), for years the standard white colouring for capsules, has been banned in food supplements in the European Union since 2022 (EU Reg. 2022/63). No compliant product can contain it anymore — but be wary of old stock and non-EU products purchased online, where it may still appear.

Dark glass: how to store bromelain

GDU units degrade over time, because light, humidity and heat reduce them month after month, even in a closed jar. The plastic of cheap bottles (PET, HDPE) is microporous and allows oxygen and moisture to pass through over time; transparent blister packs expose each capsule to light.

NUTRALAB packages its bromelain in a dark glass jar with an airtight seal: the glass blocks light, does not let moisture pass through, and does not leach anything into the contents. The activity stated on the label must hold true for the last capsule in the jar, not just the first. We explain where to keep the jar at home, and what the date printed on the packaging means, in How to store supplements: where, how and for how long.

Standard Bromelain vs. NUTRALAB Bromelain: a comparison table

If you are looking for a bromelain with a declared enzymatic activity per dose, in gastro-resistant vegetable capsules and with clean excipients, you can find it here: Gastro-resistant Bromelain 5000 GDU — 90 capsules, 2700 GDU per day.

How and when to take our Bromelain 5000 GDU

As indicated on the label: 3 capsules a day with water, preferably between meals. This is the method consistent with its use for drainage and the microcirculation. Those who use it to support protein digestion will, however, find that the literature recommends taking it with meals. The 90-capsule pack covers 30 days.

Warnings: do not exceed the recommended daily dose; keep out of the reach of children under 3 years of age; supplements are not a substitute for a varied and balanced diet and a healthy lifestyle. If you are taking medication — particularly anticoagulants or antiplatelet drugs — or are allergic to pineapple, consult your doctor before use.

Frequently asked questions

What does 5000 GDU/g mean?

GDU stands for Gelatin Digesting Unit and it is the unit used to measure the proteolytic activity of bromelain. 5000 GDU/g indicates the activity of one gram of raw material: in the 540 mg daily dose of our Bromelain 5000 GDU, the activity corresponds to 2700 GDU.

What is the difference between a 2500 and a 5000 GDU bromelain?

The titration describes the activity of one gram of raw material: for the same weight, a 5000 GDU/g bromelain is twice as active as a 2500 GDU/g one. The number to compare between products, however, remains just one: the actual enzymatic activity per daily dose.

Better on a full or empty stomach?

It depends on the goal. For the drainage of fluids and the microcirculation, the indicated intake is between meals, and this is the method stated on the NUTRALAB label. To support protein digestion, the literature describes taking it with meals.

Why is bromelain in capsules and not tablets?

Because for an enzyme, the form matters. The compression needed to produce a tablet generates friction and heat that can reduce enzymatic activity, as documented by pharmaceutical technology studies on enzymes of the same family. Our capsule, in addition to not requiring compression, is also gastro-resistant: a plant-based shell of HPMC (E 464) and gellan gum (E 418) that opens in the intestine, not in the stomach.

Why do some bromelain products irritate the stomach?

A proteolytic enzyme released directly into the stomach can be unpleasant for more sensitive mucous membranes: it is one of the limitations of unprotected forms. The gastro-resistant capsule passes through the stomach intact and releases the enzyme further on, in the small intestine.

Is bromelain useful when legs feel swollen and heavy?

The drainage of body fluids in case of leg heaviness is one of the physiological effects recognised for pineapple (stem and fruit) by ministerial guidelines, along with microcirculation function. For this type of goal, the indicated intake is between meals.

Does it contain allergens?

Our label does not declare any allergens. However, if you are allergic to pineapple, consult your doctor.

Further reading

• Capsules or tablets: how to choose the form of a supplement
• Excipients in supplements: what they are for and which ones matter
• How to choose a quality supplement: the complete guide

Bibliography

1. Kansakar U., Trimarco V., Manzi M.V., Cervi E., Mone P., Santulli G. Exploring the Therapeutic Potential of Bromelain: Applications, Benefits, and Mechanisms. Nutrients. 2024;16(13):2060. PMID 38999808 — doi.org/10.3390/nu16132060
2. Varilla C., Marcone M., Paiva L., Baptista J. Bromelain, a Group of Pineapple Proteolytic Complex Enzymes (Ananas comosus) and Their Possible Therapeutic and Clinical Effects. A Summary. Foods. 2021;10(10):2249. PMID 34681298 — doi.org/10.3390/foods10102249
3. Hikisz P., Bernasińska-Słomczewska J. Beneficial Properties of Bromelain. Nutrients. 2021;13(12):4313. PMID 34959865 — doi.org/10.3390/nu13124313
4. Sharma M., Sharma V., Majumdar D.K. Influence of Tableting on Enzymatic Activity of Papain along with Determination of Its Percolation Threshold with Microcrystalline Cellulose. Int Sch Res Notices. 2014;2014:140891. PMID 27350972 — doi.org/10.1155/2014/140891
5. Kuny T., Leuenberger H. Compression behaviour of the enzyme beta-galactosidase and its mixture with microcrystalline cellulose. Int J Pharm. 2003;260(1):137-47. PMID 12818818 — doi.org/10.1016/s0378-5173(03)00253-9
6. Ministry of Health — Ministerial reference guidelines for the physiological effects of botanical substances and preparations (Annex 1, DM 9 July 2012 and subsequent DM 10 August 2018): entry Ananas comosus (L.) Merr.

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Food supplements are not intended as substitutes for a varied and balanced diet and a healthy lifestyle. This article is for informational purposes and is not a substitute for medical advice.