Neem as an Immune-System Booster

While neem is known around the world as “The Village Pharmacy,” its most important benefit may be its immune-boosting properties. Researchers don’t know how it works, but they do know it carries a one-two punch, boosting both the lymphocytic and cell-mediated immune systems.

THIS REPORT IS PROVIDED FOR EDUCATIONAL PURPOSES ONLY. WHENEVER POSSIBLE, WE HAVE INCLUDED LINKS TO THE FULL TEXTS OF ARTICLES QUOTED. HOWEVER, NONE OF THESE STATEMENTS HAVE BEEN EVALUATED BY THE U.S. FOOD AND DRUG ADMINISTRATION. NEEM TREE FARMS DOES NOT SELL PRODUCTS THAT ARE INTENDED TO DIAGNOSE, TREAT, PREVENT OR CURE ANY DISEASE.

The fact that neem boosts the cell-mediated immune (CMI) system is particularly important to most people. Led by “Killer T” cells, the CMI system is the body’s first defense against infection, particularly viruses. It recognizes small parts of a virus and then destroys them with toxic chemicals.

Much of the research on Killer T cells – more formally known as cytotoxic cells – focuses on treating cancer in Swiss mice. Sixteen separate reports published in peer-reviewed journals with abstracts in the National Institutes of Health library specifically look at cytotoxic cells and their role in suppressing tumors, mostly in mice but also in human cancer cells in test tubes.

It’s so complicated that you will almost certainly need an advanced education to understand it so we’ll just include the link to the abstracts here instead of trying to translate.

More recent research focuses on taking the lessons learned from suppressing tumors and how that could be used to combat Covid. The virus infects many of the immune system cells, including monocytes and macrophages, that exhaust T-cell energy. The neem leaf glycoprotein helps to optimize those T-cells, according to a report published in the peer-reviewed journal Cytokine.

Some of the earliest research on neem looks at how neem functions as a contraceptive, specifically focusing on its immune-boosting properties. The first was published in Immunology & Cell Biology, where researchers describe how neem increases the body’s CMI  response in both rodents and primates, effectively terminating their pregnancies.

Another report in the American Journal of Reproductive Immunology supports those findings, noting that it initially stimulates T cells and macrophages and then causes an elevation of both immunoreactive and bioactive TNF-alpha and gamma-interferon. 

A follow-up study in the Journal of Ethnopharmacology reported that long-term use of neem oil, up to 10% of body weight, showed no apparent toxic effect but completely abrogated pregnancies. All three studies note that the effect of neem lasts for one or two cycles, and animals born after treatment with neem showed no damage.

Other research on how neem boosts immune systems looks at diverse but economically important animals, including mice, chickens, bass, catfish and even buffalo calves.

The calves were fed an additive that included neem seed cake for four months. Those who received the supplement showed increase in both their CMI and humoral immune responses.

Chickens with immunosuppressed systems that were fed powered dry neem leaves showed significantly enhanced humoral and cell-mediated immune responses to a common virus. The scientists concluded that neem leaf could be beneficial in immunosuppressed conditions in poultry.

In another chicken experiment, birds fed neem leaves showed higher levels of antibodies that could minimize the need for antibiotics typically used to treat Newcastle’s and infectious bursal viruses.

Seabass fingerlings were fed various concentrations of neem and then injected with a lethal dose of a vibrio infection. Not only did the survival rate increase because of the fish’s enhanced immune systems, but they also gained more weight more quickly.

Striped catfish were used to screen the immune-modulatory action of neem and other plant extracts. Neem and four others induced significant changes in pro-inflammatory, antiviral and adoptive immune cytokines that enhance the fish’s health.

Although most of this research has been conducted in animals and considers very specific types of antigens and infections, the overall results indicate that neem significantly boosts human immune systems. However, it also makes it clear that anyone (male or female) who is pregnant or planning to become pregnant should avoid using neem.