Moderation, not high doses urged when using supplements

Vitamin C is essential for good health.

Science has proved that much.

But is it possible to get too much of a good thing?

If you’re a die-hard fan of dietary supplements loaded with vitamin C, the answer might be yes. And at a cost of five to seven times the price of multivitamins, you might also be wasting your money.

And who can afford that in this economy?

Devotees of popular liquid vitamin C supplements, such as Emergen-C and Airborne, swear the fizzy drinks prevent illness, especially the common cold.

“After taking Emergen-C, I have not been sick at all,” wrote one reviewer of Emergen-C on Amazon.com.

“Whenever I feel like I am coming down with something, I use three of these (Airborne) a day and, more often than not, it takes care of the cold,” wrote another reviewer.

Emergen-C, a powder sold in small packets, and Airborne, effervescent tablets packaged in tubes, are two of the most popular vitamin C supplements on the market. Both are mixed with water to create sweet, bubbly, fruit-flavored drinks.

Widespread anecdotal praise has prompted consumers to stock up on the products, especially during cold and flu season, but doctors say people could be putting themselves at risk for adverse health conditions if they consume extremely high doses of vitamin C every day.

Health claims of such dietary supplements, which are not evaluated by the U.S. Food and Drug Administration, include increased energy and better immunity.

Solid research to support those claims, however, doesn’t exist, said Dr. Cheryl Beighle, medical director of integrative services for the Providence Regional Cancer Partnership and a pediatrician with The Everett Clinic.

“I truly believe in using supplements and herbal products,” Beighle said. “I go by where the research is and where the data is. We don’t have the data.”

While some studies have shown minor decreases in cold severity and duration with various vitamin C treatments, there still isn’t enough evidence to merit routinely high doses, Beighle said.

Beighle tells her patients to eat foods rich in vitamin C, a strategy that has been proved to support immunity and reduce cancer risk.

“Eat an orange. There are all these things that work with the vitamin C in an orange,” she said.

Vitamin C supplements can’t duplicate nature’s formula, Beighle said. “You’re missing all that synergy and all the complementary and supporting nutrients.”

Women need 75 milligrams of vitamin C every day and men need 90, according to 2004 data from National Academy of Sciences, which sets the official RDA or recommended daily allowances used in nutritional information labeling.

That’s roughly the amount of vitamin C found in a large orange or half a cup of red bell pepper pieces.

“We have a tendency to use supplements to replace good health habits, like nutrition, like getting enough sleep, like exercising,” Beighle said. “Food is your best way to get nutrients.”

Consumers, practicing what critics have deemed folk medicine, figure if something is good for them, then a lot more must be better.

Both Emergen-C and Airborne contain 1,000 mg of vitamin C per serving. Directions on Emergen-C packaging recommend two to four packets per day. Airborne’s directions say users can consume up to three tablets per day.

That would be too much vitamin C, said Dr. Michael Tamber, an endocrinologist at The Everett Clinic.

“Essentially what they’re going to have is very expensive urine,” Tamber said.

High vitamin C doses can increase the risk of kidney stones because of excess oxalates produced in the urine, Tamber said.

The National Academy of Sciences recommends no more than 2,000 mg of vitamin C per day. Suggested limits for children are lower, 650 mg for ages 4 to 8, for example.

“Megadoses are actually loading up your body with chemicals,” Tamber said, adding that the liver must also process excess vitamins and nutrients.

High doses of vitamin C can cause some people to suffer headaches, nausea, vomiting, heartburn, abdominal cramps or severe diarrhea, according to the National Institutes of Health.

Vitamin C supplements can also interact with drugs such as aspirin, acetaminophen, antacids and blood thinners, according to the health institute.

Patients who insist they feel better or don’t get colds because of their vitamin C remedies could be enjoying a powerful placebo effect, Tamber said.

Emergen-C isn’t just vitamin C. It contains 24 nutrients, including seven B vitamins. Airborne, billed as the miraculous invention of schoolteacher, contains 17 vitamins, minerals and herbs.

Such drinks, depending on how much water they’re mixed with, can also provide much-needed hydration.

“Things can work. They just may not have been proven yet,” Tamber said. “If someone’s going to take 500 milligrams of vitamin C at the onset of a cold — and if they swear up and down, ‘I took it and I started feeling better,’ — is there a problem in doing that? Maybe not.”

Beighle wants to see more conclusive research, not just about vitamin C, but also for the products themselves, not something she expects to see done anytime soon.

She would also like to know the exact ingredient amounts in Airborne’s proprietary herbal formula.

Both Beighle and Tamber recommend taking multivitamins and vitamin D supplements because of widespread vitamin D deficiencies.

Most of the time, consumers don’t have deficiencies, but are searching in vain — and at considerable cost — for a magic wellness bullet, Beighle said.

Emergen-C, introduced by Alacer Corp. of Foothill Ranch, Calif. in 1978, was formulated in collaboration with Nobel Prize winner Linus Pauling, a chemist and vitamin C advocate.

In the 1970s, Pauling urged people to take high doses of vitamin C to prevent colds and even fight cancer.

Research on vitamin C across the decades, however, has been subject to debate.

According to the National Institutes of Health, more than 30 clinical trials including more than 10,000 participants haven’t proved conclusively that high doses of vitamin C can prevent or cure colds.

Alacer president Ron Fugate said in an e-mailed statement that the ingredients selected for Emergen-C, including vitamin C, B vitamins, magnesium and zinc, have been widely shown to “play a role in maintaining a healthy immune function.”

“While we encourage a healthy lifestyle of exercise, sleep and a proper diet, Emergen-C can help fill the gaps caused by life’s everyday stresses,” he said.

The makers of Airborne could not be reached for comment.

Sarah Jackson: 425-339-3037, sjackson@heraldnet.com.

Looking for vitamin C?

Find it in strawberries, oranges, grapefruit, cantaloupe, kiwi fruit, papayas, mangoes and melons.

You can also add it into your diet with fruit juices, which tend to be high in calories, or, instead, low-calorie vegetables such as peppers, broccoli, Brussels sprouts, kale, snow peas, tomatoes and sweet potatoes.

Source: American Cancer Society