Citrus fruits are tangy and tasty, yet they also combat ulcers and help prevent stomach cancer. One might think the acidic nature of fresh citrus would exacerbate an ulcer, but the opposite is true.
These conclusions have been borne out of multiple studies over the years. These have included large population studies, clinical tests and laboratory studies. These have looked at the myriad of compounds in fresh citrus fruits.
And because ulcers have also been linked with stomach cancer, the notion that fresh citrus fruits can ease ulcers as well as reduce stomach cancers is a natural conclusion.
Citrus and stomach cancer
A study from South Korea’s Jeju National University School of Medicine analyzed five large population studies that tracked stomach cancer. The studies were from the U.S., the Netherlands, Europe, China and Japan. These five studies followed 490,802 people, 4,035 people, 477,312 people, 132,311 people and 42,470 people, respectively. Yes, these were large population studies conducted by researchers from those respective countries.
Using the combined data from these studies, the researchers determined that eating fresh citrus fruits significantly decrease the incidence of stomach cancer.
They found that eating just 100 grams of citrus per day reduces the incidence of cardia gastric cancer by 40 percent. And the risk of any type of stomach cancer was reduced by 13 percent by citrus consumption.
The researchers also found a dose dependency in the relationship between citrus fruits and cardia stomach cancer. Eating 100 grams a day resulted in a 40 percent reduction in the cancer incidence. But eating 50 grams a day cut the risk by 23 percent.
What is 100 grams of citrus?
According to the USDA, an average orange weighs 131 grams. This means that by eating just one orange a day, we can exceed the 100 grams a day.
Eat two oranges a day? Even better. We can assume from the dose-dependency relationship that this will reduce our risk of gastric cancer even further.
Citrus fights destructive H. pylori
Helicobacter pylori is a bacteria species that often infects the stomach wall. It is often associated with many cases of ulcers.
In addition to being linked to ulcers, H. pylori infections have also been linked to approximately 74 percent of gastric cancer cases.
A majority of people have H. pylori in the gut. However, research has established a more destructive form of H. pylori can infect the gut. This is called CagA-positive H. pylori. The CagA stands for cytotoxin-associated gene.
This particular type of H. pylori is highly resistant to most antibiotics. We discussed how this strain of H. pylori differs from most strains that naturally inhabit many guts.
Our point here is that eating fresh citrus fruits has been shown to reduce H. pylori infections.
Researchers from Italy’s University of Messina studied the relationship between citrus and ulcers and H. pylori infections. These included laboratory studies to test citrus against H. pylori.
Types of citrus shown to fight H. pylori among multiple studies:
• Mandarins (Citrus reticulata)
• Oranges (Citrus sinensis)
• Grapefruits (Citrus paradise)
• Lemons (Citrus lemon)
• Satsuma Mandarins (Citrus unshiu)
These are just the types of citrus tested against H. pylori. Other citrus fruits will share many of the compounds of these above.
The research determined that citrus has two effects upon the microbial nature of the gut. The first is that it decreases H. pylori content. This is achieved by citrus’ antibacterial qualities.
Components in citrus that have been shown to inhibit H. pylori include neohesperidin, hesperetin, neoeriocitrin, naringin, eriodictyol, naringenin, hesperetin, geranyloxyferulic acid, boropinic acid, sudachitin and demethoxysudachitin.
Besides inhibiting H. pylori, the research has found that citrus inhibits other bacteria, including E. coli, Pseudomonas and Salmonella species. We have discussed how citrus can rival antibiotics against resistant bacteria.
The research found these components of citrus work synergistically to inhibit the growth of H. pylori. Some of the research also indicated that citrus reduces the effectiveness of urease enzymes produced by H. pylori. By blocking the urease enzymes, citrus helps block the growth of the bacterium.
Citrus and ulcers
Other studies have shown that citrus essential oils can significantly help prevent and eases ulcers. For example, a 2016 study from the School of Medicine at Turkey’s BezmiÂlem Vakif University tested 37 ulcer patients.
They were each given a citrus oil patch to place over their abdomen. The first application of the patch was given by the doctor. The doctor explained that the patch will last for between 8 to 12 hours. After that, if the pain remained, a second patch could be applied.
The citrus patch allowed for the absorption of the active citrus components into the stomach region.
Five days after the first application, the patients were given pain assessments using the 100 VAS system, as well as the OHIP-14 pain assessment system.
The researchers found that pain relief was accomplished within 5.6 hours, up to 16.5 hours. The pain decrease was significant. 78 percent of the patients reported significant decreases in discomfort and improved digestive function. The group as a whole gave the experience a 7 out of 10 in terms of successful treatment of their ulcers.
Citrus feeds probiotic bacteria
The other component discovered by the researchers was citrus’ ability to feed the gut’s probiotic populations. This makes citrus an effective prebiotic.
The researchers found that pectin oligosaccharides present in the inner peels of citrus provide prebiotic properties. The research showed that these oligosaccharides increased populations of bifidobacteria and lactobacilli in the gut.
This prebiotic property of citrus increases populations of these healthy bacteria. The researchers stated:
“The results obtained demonstrated that bergamot oligosaccharides resulted in a high increase in the number of beneficial bacteria, such as bifidobacteria and lactobacilli, whereas the clostridial population decreased.”
Does this mean we have to eat citrus peel?
Yes and no. Citrus peel is typically a quarter inch or more thick. It begins at the outer layer where the pigment is located, ending at the citrus segments. Even when we peel a citrus fruit by hand there is a thin layer of peel remaining over the segments of the fruit.
Certainly, eating more citrus peel is a good idea. We have discussed some of the health benefits of citrus peel in previous articles.
A useful strategy might be to toss the whole unpeeled citrus fruit into a blender together with other fruit. This can make a wonderful and tangy fruit smoothie. If the outer rind of the fruit seems a bit damaged, we can cut the outer rind off, still leaving much of the peel intact.
Fresh citrus versus orange juice
Connecting all these realities and studies together creates a grander image of how fresh citrus fruits fight ulcers and stomach cancers.
The various plant compounds in fresh citrus provide a myriad of benefits. These include stimulating healthy stomach lining, inhibiting H. pylori outbreaks, and preventing cancer cells from growing.
We should note that pasteurized citrus juices won’t necessarily maintain the same properties as fresh citrus fruits. That’s because the pasteurization process removes many of the flavonoids and other critical compounds. This is because many of these are heat sensitive.
Pasteurization also tends to increase the acidic content of the juice at the same time. These acids may actually exacerbate an ulcerative condition.
In addition, many of these compounds are contained within the pulp and the rind of the citrus. Juices are often stripped of these essential parts of the citrus fruit during processing. Yet these are the very elements that really help the stomach.
Should we expect less from such a tangy and tasty fruit?
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Case Adams is a California Naturopath and a Board Certified Alternative Medicine Practitioner with a PhD in Natural Health Sciences, and diplomas in Homeopathy, Aromatherapy, Bach Flower Remedies, Blood Chemistry, Clinical Nutritional Counseling and Colon Hydrotherapy. He has authored 26 books on natural healing strategies.