Balz Frei

From the Director

Balz Frei, Ph.D.
Professor of Biochemistry & Biophysics
Director and Endowed Chair
Linus Pauling Institute

This spring, the U.S. Department of Agriculture will publish its new food guide pyramid. Several important changes are expected to be made to the current pyramid, which many nutritionists believe does not give the best nutrition advice and may even have helped fuel the obesity epidemic. The amount and types of carbohydrates and fat in a healthy diet remain topics of great interest and some controversy.

One thing we know for sure is that there are “good” and “bad” fats, much like the “good” and “bad” cholesterol in your blood (high-density and low-density lipoproteins, respectively). The good dietary fats are the unsaturated fats found in vegetable oils, nuts, and fish, whereas the bad fats are the saturated fats, in particular animal fats, such as those in meat, bacon, sausage, butter, milk, and cheese, and the trans fats, especially partially hydrogenated vegetable oils found in many processed foods. The amount of fat in one’s diet isn’t as important as the type of fat. Indeed, the good, unsaturated fats can help decrease blood levels of bad cholesterol and increase levels of good cholesterol, thereby lowering the risk of heart disease. In contrast, the saturated and trans fats increase blood levels of bad cholesterol and the risk of a heart attack and stroke. Thus, the current food guide pyramid is not quite correct in placing all types of fats and oils at the top of the pyramid—to be “used sparingly.”

Much like the good and bad fats, there are “good” and “bad” carbohydrates. The good carbohydrates are those in whole grain foods, such as whole grain breads and cereals and brown rice, whereas white bread, white rice, pasta—and most likely potatoes—contain the bad carbohydrates. This is where the current food guide pyramid seems to err the most—in the advice to eat lots of bread, cereal, rice and pasta, without qualifying what type—whole or refined.

The most important advice that the new food guide pyramid is likely to give is to maintain a healthy weight, which means a body mass index of less than 25 kg/m2. (To calculate your BMI, take your weight in kilograms and divide it by the square of your height in meters—or go to and enter your height and weight). The only way to lower BMI is by eating fewer calories than are being used up in the body every day. Only eating less or exercising more—or even better, both together—can achieve this! And there is no fad diet or “magic pill” that will make it easier to achieve that goal.

Where in this picture are vitamin C and the other dietary supplements that the eminent founder of our Institute, Dr. Linus Pauling, so passionately endorsed? They are very important as “health insurance”—especially a daily multivitamin/mineral—to make sure one gets at least the Recommended Dietary Allowance (RDA) or Daily Value (DV) of each vitamin and essential mineral. Some extra vitamin C to get at least 400 mg/day can be helpful for staying healthy and warding off disease.

Of course, supplements should never substitute for a good diet and a healthy lifestyle, which are the cornerstones of good health. I believe that Dr. Pauling’s and LPI’s advice for a healthy diet and vitamin C supplements are very similar. In a 1974 radio interview, Dr. Pauling noted “the first 250 mg [of vitamin C] is more important than any later 250 mg. The first 250 mg leads you up to the level where the blood is saturated. You can achieve a higher volume [concentration] in the blood by a larger intake, but you get much better improvement for the first 250 mg than for additional grams.” And in the same year, in an article in the Saturday Evening Post, he said, “My conclusion is that by eating good unadulterated natural food, with emphasis on green and yellow or red vegetables, by a proper intake of vitamin C, vitamin E, and other vitamins, by largely eliminating ordinary sugar from the diet, and by some physical exercise every day, the process of deterioration that ultimately leads to death can be postponed an average of twenty years.” Thirty years later, Dr. Pauling’s advice is just as valid!

Last updated May, 2005

Micronutrient Research for Optimum Health

Table of Contents LPI Home Page Send an email to LPI