If you are trying to get enough vitamin C  in your diet, don’t look to the present recommended dietary allowance (RDA) for guidance because it’s way too low. That’s the conclusion of a study released in the June 2012 issue of Critical Reviews in Food Science and Nutrition. The researchers concluded that to help prevent disease and maintain optimum wellness, the present vitamin C RDA of 75 mg for women and 90 for men should be raised to 200 mg daily for all adults.

This is important because many Americans already aren’t getting enough of this key vitamin. “Various studies in the U.S. and Canada have found that about a quarter to a third of people are marginally deficient in vitamin C, and up to 20 percent of some populations are severely deficient,” said Balz Frei, PhD, professor and director of biochemistry and biophysics at the Linus Pauling Institute at Oregon State University, where the study took place. 

In an interview with Wellness Times, Frei, who is considered one of the world’s leading experts on the role of vitamin C and health, voiced his frustration that the same stringent study methods are used to test both micronutrient (like vitamin C) safety and unproven, potent pharmaceutical drugs. “These types of trials are ill suited to demonstrate the disease-prevention capabilities of substances that are already present in the human body and required for normal metabolism,” he said.

How likely will the vitamin C RDA be raised in the near future? “Not very likely,” said Frei. “It has been a long struggle to make the Food and Nutrition Board and the Institute of Medicine adopt more reasonable scientific standards when it comes to nutrients versus drugs. This recently published paper is another attempt to nudge them in that direction.”

Important factors that this recent data shows include:

• 500 mg of vitamin C significantly reduced both systolic and diastolic blood pressure (the top and bottom numbers in a blood-pressure reading).
• Vitamin C reduced mortality from heart disease by 60 percent in a European study featuring 20,000 adults.
• Men with low blood levels of vitamin C had a 62 percent higher risk of cancer-related deaths compared to men with the highest levels of the vitamin.

Frei pointed out that although this data applies to the two leading causes of disease-related deaths in North America, vitamin C affects more than just cancer and heart disease. “Even marginal deficiency can lead to malaise, fatigue and lethargy, while higher levels of vitamin C can enhance immune function and reduce inflammatory conditions,” he said. 

Frei also said supplementation is likely necessary because it can be difficult to obtain enough vitamin C from diet alone. To get the 200 mg that Frei and his colleagues are recommending, a person needs to eat five to nine servings of fruits and raw or steamed vegetables a day, and drink a 6-ounce glass of orange juice. 

The good news is that even if the RDA is not increased, you can add more vitamin C to your daily routine safely and economically by taking supplements and eating more fruits and vegetables. In addition to citrus, other fruits high in vitamin C include strawberries, kiwi and papaya. Bell peppers, kale, broccoli, cauliflower and Brussels sprouts are also high in vitamin C.