Questions and Answers About Modified Citrus Pectin
What is modified citrus pectin?
Pectin is a type of polysaccharide (a carbohydrate with many small sugar molecules that are chemically linked). Pectin is found in the cell walls of most plants and has gel-like qualities that are useful in making many types of food and medicine.
Citrus pectin is found in the peel and pulp of citrus fruits such as oranges, grapefruit, lemons, and limes. Citrus pectin can be modified with high pH and heat to break its molecules into smaller pieces. Modified citrus pectin (also called MCP) can be digested and absorbed by the body.
How is MCP administered or consumed?
MCP may be taken by mouth in powder or capsule form.
Have any preclinical (laboratory or animal) studies
been conducted using MCP?
A study in prostate cancer cells compared 3 different kinds of pectin: citrus pectin, PectaSol (a dietary supplement with MCP), and fractionated pectin powder. Prostate cancer cells treated with the pectin powder had more damage than those treated with citrus pectin or PectaSol. However, when citrus pectin was modified by heating it, it caused the same amount of damage to prostate cancer cells as the pectin powder.
Only a few studies have reported the effects of MCP in animal models of cancer, including one prostate cancer study. Rats injected with prostate cancer cells and treated with MCP showed less spread of the cancer to the lungs but no effect on tumor growth at the original cancer site.
Have any population studies or clinical trials (research studies with people)
of MCP been conducted?
A few studies in prostate cancer patients suggest that MCP may have some anticancer benefits.
In a study of patients with advanced solid tumors, including prostate cancers, MCP powder in water was given 3 times/ day for at least 8 weeks. The study showed some quality of life improvements in physical functioning, overall health, fatigue, pain, and insomnia. About one-fourth of patients showed stable disease after 8 weeks of treatment and a smaller number had stable disease for more than 24 weeks. Since the study did not include a group of patients who did not receive MCP for comparison, it was not designed to be able to tell if any of these changes were due to the addition of MCP. The primary goal of the study was to determine if MCP would be well tolerated by cancer patients, and it was.
In a study of the effect of MCP on prostate-specific antigen (PSA) doubling time (how long it takes PSA levels in the blood to increase by 100 percent), prostate cancer patients who had rising PSA levels were given 6 PectaSol capsules 3 times/ day for 12 months. After treatment, 7 out of 10 patients showed a slowing of PSA doubling time.
Have any side effects or risks been reported from MCP?
Two studies of MCP showed that most patients had very few side effects. Itching, stomach upset, and gassiness were reported in one study. In another study, 3 patients had abdominal cramps and diarrhea that went away when their treatment was stopped.
Is MCP approved by the U.S. Food and Drug Administration (FDA)
for use to prevent or treat cancer in the United States?
MCP is available in the United States in food products and dietary supplements. Because dietary supplements are regulated as foods, not as drugs, FDA approval is not required unless specific claims about disease prevention or treatment are made.
Current Clinical Trials
General information about clinical trials is also available from the NCI Web site.