60 Percent of Cancer Patients Try Nontraditional Methods

Leslee Flasch believed that dietary supplements would make her stronger and help fight the cancer -- a belief her other surviving sister, Donna Flasch, still shares despite Leslee's death.

But getting nutrients from pills is different than getting them from a balanced diet, nutrition experts say.

"So many people think, 'Well, if a little bit is good, then more is better,' and that's definitely not true with most dietary supplements," said Kathy Allen, a Moffitt Cancer Center dietitian.

Examples of potential harm:

• Vitamin E can prolong bleeding time and has forced cancellation or delay of cancer surgeries; some studies suggest it may raise the risk of certain cancers.
• Beta carotene, a precursor of vitamin A, may raise smokers' risk of developing lung cancer. 
• Folic acid supplements may raise the risk for precancerous growths in the colon. 
• Vitamin C in large doses may help cancer cells resist chemo and radiation.

Herbals and dietary supplements can undermine cancer treatments in ways that patients can't feel and doctors can't measure. When a treatment fails, it's impossible to say whether it was due to the person's cancer or because a supplement subtly interfered.

"We know that there's some harm going on. We just don't know the magnitude of it," said Dr. Jeffrey White, the National Cancer Institute's complementary and alternative medicine chief.

Studies show that as many as two-thirds of cancer patients who use unproven remedies do not tell their doctors. Sometimes it is because they fear disapproval, but often they do not realize this can harm their care.

"I didn't think they were medications. They're not prescription, they're not drugs. This is all natural substances," said Vince Palella, a Bradenton, Fla., prostate cancer patient.

A Moffitt dietitian, Diane Riccardi, discovered that Palella was taking dozens of pills a day, including a saw palmetto extract. That supplement might have interfered with his hormonal cancer treatments or the monitoring to see if the those treatments were working.

"There's absolutely no way of knowing" if it did, Riccardi said.

Another supplement that can pose a risk for prostate cancer patients is DHEA, which can affect testosterone levels, said Phyllis Matthews, a urology nurse practitioner at a group of Veterans Affairs clinics in the Denver area.

Cancer doctors also worry about isoflavones and other soy-related supplements; some research suggests they might stimulate breast tissue. Breast cancer patients on tamoxifen or aromatase inhibitors like Femara or Arimidex should not use red clover, dong quai or licorice because of estrogen-stimulating components, say guidelines from the Society for Integrative Oncology.

In June, the FDA sent 25 warning letters to sellers of teas, pills and other products sold on the Internet that falsely claim to cure, treat or prevent cancer. They included bloodroot, shark cartilage, coral calcium, cesium, ellagic acid, cat's claw, Essiac tea and various mushrooms.

In September, the Federal Trade Commission charged five companies with making false and misleading claims for cancer cures and reached settlements with six others. The agency also started a bogus cures Web site to help consumers. A statement explained its reasoning:

"When you're battling cancer, the last thing you need is a scam."