One regret I have is not being able to meet Linus Pauling, the biochemist best known in nutrition circles for his views on vitamin C. In the last years of his life, he resided just down the road from us. He may not have wanted a visit from a stranger, but I wish I had at least tried.

If the name doesn’t ring a bell, Pauling was a Nobel Prize winner and considered by some to be the founding father of molecular biology. According to the Linus Pauling Institute (LPI.oregonstate.edu) — a research center founded in his honor at Oregon State University — his work helped set the stage for the field of biotechnology.

And his research paved the way for Oregon State to continue to identify how various components in food affect human health and longevity. I refer to this site often.

For example, these researchers have named vitamin C in their “top 10 micronutrients for aging well.” Besides protecting our immune system and helping heal skin wounds, there is good evidence that vitamin C supports heart, brain and bone health.

And there are other important facts about this nutrient. For instance, it’s essential that we ingest vitamin C from food or supplements every day. That’s because, unlike most animals, our human bodies do not have the ability to manufacture vitamin C on our own.

Vitamin C is a potent antioxidant — a substance that protects our cells from damage caused by everyday living. Another good reason to ingest it daily.

Although vitamin C has notoriety as a preventive measure against the common cold, taking a daily supplement does not reduce our risk of getting a cold, according to research. It can, however, shorten the duration of a cold if we are taking it before we start to notice symptoms. Taking it after you start to feel sick does not appear to have any benefit.

We need more vitamin C as we age. And smokers need more vitamin C due to the increased “oxidative stress” that occurs to the body from the toxins in cigarette smoke.

The current Recommended Daily Allowance for vitamin C is 90 milligrams a day for men and 75 milligrams for women. (Pregnant and breastfeeding women need more.) Extensive research, however, has led the experts at the Linus Pauling Institute to recommend a daily intake of 400 milligrams of vitamin C for all healthy adults.

It is possible to get this much with food if we eat several servings of vitamin C-rich foods daily. Good sources include grapefruit, oranges, strawberries, kiwifruit, sweet red peppers and broccoli. Remember, heat destroys vitamin C. So don’t overcook these foods.

Lastly, the vitamin C in supplements is identical to the vitamin C found in food. Just look for “ascorbic acid” or “sodium ascorbate” on the ingredient label.

Barbara Intermill is a registered dietitian nutritionist and syndicated columnist. She is the author of “Quinn-Essential Nutrition: The Uncomplicated Science of Eating.” Email her at barbara@quinnessentialnutrition.com.