Noni As A Functional Food

By Dr. Florita S. Maslog, PhD (Microbiology), M.Sc., B.S. Pharmacy, Med Tech (ASCP), F(PAM)
QA/QC Manager & In-house Researcher, Philippine Morinda Citrifolia, Inc. (PhilNONI), 2014–2025 — now Scientific Advisor Emeritus
Published: 8/9/2026

1. What is a functional food?

In short: a functional food is a food that provides nutrition and also contains bioactive compounds associated with health benefits beyond basic nutrition.

Functional foods, also known as nutraceuticals, are — per the U.S. National Academy of Sciences, Food and Nutrition Board — highly nutritious and associated with a number of health benefits. For example, they may help protect against disease, prevent nutrient deficiencies, and support proper growth and development.

Can noni juice be considered a functional food?

According to Almeida, Oliveira and Hotza (2019), and to analyses by Senthilkumar et al. (India, 2024) and Lima et al. (Rio Grande, Brazil, 2017), to be called functional a food should contain phytochemicals with bioactive properties — such as terpenoids, flavonoids, alkaloids, steroids and glycosides, among others. In the literature, Morinda citrifolia is also reported to contain vitamins (A, B2, B6, B9, B12) and minerals (iron, calcium, potassium, copper, magnesium, sodium, phosphorus and selenium).

A note on vitamin C specifically: the vitamin C present in the finished PhilNONI bottle is added ascorbic acid, included to restore vitamin C lost during ambient storage. It should not be read as vitamin C delivered by the fruit as consumed.

Most of these phytochemicals have already been isolated in the Philippine variety of M. citrifolia in our PhilNONI (PMCI) laboratory in Los Baños, Laguna, Philippines (Maslog, 2023). All of the minerals listed above have been isolated from the local noni juice by the BIOTECH laboratory at the University of the Philippines Los Baños (UPLB). The presence of several vitamins in noni is also reported in the wider literature.

In laboratory (in-vitro) assays of PhilNONI's finished bottled product, Maslog (2023, Silliman Journal Vol. 64) documented antibacterial susceptibility in three common pathogens: Salmonella typhi, Staphylococcus aureus and Escherichia coli. These are laboratory findings about the product in vitro; they are not a claim that drinking the juice treats or prevents infection in people.

The U.S. CDC also emphasizes the importance of vitamins and minerals in health. On this basis noni fits within the functional-food category discussed above. In the literature its compounds have been studied for antioxidant, immunomodulatory and adaptogenic activity.

Functional foods differ from medicines: there is no need to combine several synthesised chemicals as in pharmaceutical drugs. In noni, natural bioactive substances, together with vitamins and minerals, are already present in the plant.

2. What is noni, and why has it been traditionally used?

In short: noni (Morinda citrifolia) is a tropical tree native to the Southeast Asia–Australasia region — noni's origin zone — and long used traditionally as a topical preparation and a general tonic.

Noni (Morinda citrifolia) is an evergreen shrub or small tree that grows throughout the tropical regions of the Pacific Ocean, from Southeast Asia to Australasia. It grows abundantly in the coastal regions of the Philippines. Traditionally, preparations from the roots, leaves and flowers were used topically for joint pain, wounds and skin conditions; the fruit was used for fever, colds and stomach pain; and later the juice was used as a general tonic.

3. Why does noni smell and taste the way it does?

In short: ripe noni gives off a pungent, cheese-like aroma from short-chain fatty acids, and tastes sharply sour — characteristics that intensify as the fruit fully ripens.

When noni fruit is picked it immediately releases its pungent aroma — a sharp, cheese-like stench caused by caproic and caprylic acid, the same short-chain fatty acids found in aged blue cheese.

Its taste is deeply bitter, tangy and sour, like vinegar.

A fully ripe fruit has soft, translucent yellow-to-white skin, edible flesh and edible seeds. At full ripeness the aroma reaches its peak strength. These taste and odor qualities are usually softened after fermentation, and the juice can be made more palatable with a non-glycemic sweetener.

4. What happens when noni is fermented?

In short: fermentation is a natural, beneficial process in which the fruit's own enzymes and resident microorganisms convert its sugars over time, producing an acidic, bioactive-rich juice.

When noni ferments, its natural enzymes and resident microorganisms break down its sugars over weeks or months. As in any fruit fermentation, sugars are converted to alcohol, and the result is an acidic juice rich in bioactive compounds — notably iridoids.

5. Why do clean processing and microbial control matter?

In short: because a functional food is only as good as its safety. PhilNONI operates under an FDA-enforced Good Manufacturing Practice (GMP) manual and complies annually with HACCP food-safety requirements.

Our company maintains a Good Manufacturing Practice (GMP) manual enforced by the Food and Drug Administration (FDA) — a prerequisite for product safety, quality and meeting regulatory standards. GMP requires systems that ensure proper design, monitoring and control of the manufacturing process and facilities; a strong quality-management system; appropriate quality of materials; proper operating procedures; a reliable testing laboratory; and prevention of contamination, mix-ups and errors.

The company also complies annually with Hazard Analysis Critical Control Point (HACCP) — a preventive food-safety management system used to identify, evaluate and control biological, chemical and physical hazards during the production, processing and handling of food.

6. What compounds have been studied in noni — and what were they studied for?

Researchers have studied noni's phytochemicals for a range of biological activities. The list below summarises what these compound classes have been studied for in the scientific literature. It is a summary of research interest, not a statement of what the product does, and it is not a claim to prevent, treat or cure any condition.

Compound classes and their studied activities

• Steroids — studied for anti-inflammatory and immunomodulatory activity.
• Glycosides (incl. anthraquinones, coumarins) — studied for antimicrobial and antioxidant activity.
• Anthraquinones — studied by Maslog, F. for antimicrobial and anti-inflammatory activity.
• Phenolic compounds — studied by Maslog, F. for antioxidant and antibacterial activity.
• Tannins — studied by Maslog, F. for astringent and antimicrobial activity.
• Terpenoids — studied by Maslog, F. for calming the nerves.
• Alkaloids — studied for a range of bioactivities including antimicrobial activity.
• Carbohydrates — sugars such as glucose serve as a basic energy source for the body's cells.
• Flavonoids — studied for antioxidant, immunomodulatory and antibacterial activity.
• Saponins — studied for antioxidant activity and for supporting normal blood-lipid levels.
• Proteins and amino acids — studied by Maslog, F. for immunomodulatory activity.
• Organic acids — studied by Maslog, F. for antimicrobial (including antifungal) activity.

7. What noni research can and cannot tell us

In short: we rely on laboratory studies published in reputable journals, and we treat personal experience as supportive context — never as proof.

We rely on laboratory studies conducted and published in reputable, peer-reviewed journals.

We value personal experiences that come with evidence of positive results, but we do not treat unverified anecdotes as proof.

8. A personal reflection: Dr. Crispin Maslog, 95

The following is a personal reflection shared by Dr. Florita Maslog about her husband. It is one family's experience and is offered as personal context only — not as evidence of any health benefit, and not as a claim that noni prevents, treats or cures any condition.

Many things affect ageing: genetics, and access to resources such as food, clean water, clean air, a safe environment, lifestyle, culture and medical care.

By genetics, Dr. Maslog might not be expected to still be here. His parents died before reaching their 60s and 70s; of seven siblings, only he — the eldest — and his youngest sister are still living. Twenty years ago he had a triple heart bypass.

He lived a demanding life: a journalism professor at Silliman University and UPLB, travelling abroad for conferences nearly every year from 1970 to 2000, later serving as a graduate-school dean in Manila, teaching in the United States and at Nanyang Technological University in Singapore, where he lived through the SARS epidemic — and, later, the COVID-19 pandemic.

In 2014, when Dr. Florita Maslog joined PMCI, she and her husband began drinking noni juice daily. He has taken it faithfully since, and says he feels better, sleeps well and has continued to play tennis. He personally believes his daily noni has been part of his wellbeing through these years.

References

Maslog, F. S. (2023). Isolation of phytochemical components in the Philippine Morinda citrifolia variety (PhilNONI). Silliman Journal, 64(2): 9–24. su-journal.su.edu.ph/index.php/sj/article/view/440

Maslog, F. S. (2023). Antibacterial susceptibility of PhilNONI juice versus Salmonella typhi, Staphylococcus aureus and Escherichia coli. Silliman Journal, 64(1): 106–119. su-journal.su.edu.ph/index.php/sj/article/view/382

Almeida, E. L., Oliveira, D., & Hotza, D. (2019). Properties and applications of Morinda citrifolia (noni). Comprehensive Reviews in Food Science and Food Safety, 18. doi.org/10.1111/1541-4337.12456

Senthilkumar, O., et al. (2024). Bioactive components in functional foods: mechanism of action and impacts on health, with a focus on COVID-19 — a review. Current Research in Nutrition and Food Science Journal, 12(3): 1035–1061. foodandnutritionjournal.org

Lima, A. M. S., Araújo, R. M. S., Sousa, J. C. S., et al. (2017). Biotechnological potential assessment of noni fruit (Morinda citrifolia Linn). MOJ Food Processing & Technology, 5(4): 337–341. doi.org/10.15406/mojfpt.2017.05.00133

Frequently asked questions

Is noni juice a medicine?
No. Noni juice is a food supplement. This article describes food science and laboratory research and does not make disease-treatment claims.

What compounds does noni contain?
Noni contains phytochemicals such as terpenoids, flavonoids, alkaloids, steroids and glycosides, several of which have been isolated in the Philippine variety in the PhilNONI laboratory (Maslog, 2023).

Why does noni juice taste and smell strong?
The pungent, cheese-like aroma comes from short-chain fatty acids (such as caproic and caprylic acid), and the taste is naturally sharp and sour.

← Back to the PhilNONI Research hub