Foods Rich in Vitamin C

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In the 18th century, the course of history may have been changed by, of all things, lemon juice.

At least, that's a claim made by the Science History Institute in Philadelphia. Up to that point, one of the most devastating diseases in the world was scurvy. A horrifyingly gruesome and potentially fatal disease, scurvy can cause lethargy, anemia, spontaneous bleeding, excruciating pain and swelling and breakdown of the gums leading to tooth loss.

Seafarers were at high risk, with scurvy killing more than 2 million sailors from late-15th to the mid-19th century. "The problem was so common that shipowners and governments assumed a 50% death rate from scurvy for their sailors on any major voyage," according to the Science History Institute.

In 1795, a physician named Gilbert Blane convinced the British Royal Navy to supply its sailors with lemon juice. "His order may well have changed the course of history because it allowed Great Britain to successfully defend itself from a Napoleon-led invasion by setting up a blockade of the English Channel. This blockade, during which many ships spent months on the water without coming to port, went on for 20 years - a feat that scurvy would never have allowed," writes the Science History Institute.

Yet it took nearly a century longer before anyone understood why lemon juice - and other fruits and vegetables -prevented scurvy. Turns out, as most of us know today, it was because of vitamin C.

A Potent Antioxidant

Any discussion of vitamin C takes Nancy Farrell Allen, a registered dietitian nutritionist and owner of Farrell Dietitian Services in Fredericksburg Virginia, back to those afflicted sailors. "They didn't necessarily worry about storms or pirates, but they feared scurvy," says Farrell Allen, an instructor at Rosalind Franklin University of Medicine and Science and at Germanna Community College.

Vitamin C, also known as ascorbic acid, is a "potent antioxidant, meaning it neutralizes free oxygen radicals circulating through the body, and thereby decreasing the risk of disease," Farrell Allen says. "Put another way, it gobbles up the free oxygen radicals that cause inflammation and damage to our bodies."

Vitamin C also helps to form collagen in bones and teeth and plays a role in many body reactions, including immune response and the absorption of iron. "Our need for vitamin C increases with many known stressors such as infections or burns, but also with the use of several medications or even with cigarette smoking," Farrell Allen adds. "When COVID hit early in 2020, vitamin C was one of four nutrients I discussed and emphasized for use with my patients as a way to keep their immune systems recharged every day."

The amount of vitamin C you need each day depends on your age. The National Institutes of Health says infants up to 1 year old need 40 to 50 milligrams a day. That goes down to 15 mg between ages 1 and 3, increasing to 65 to 75 mg a day for teens. For adults, the daily recommendations are:

• Adult men: 90 mg.
• Adult women: 75 mg.
• Pregnant women: 85 mg.
• Breastfeeding women: 120 mg.
• Smokers: add 35 mg to the above totals.

Best Sources of Vitamin C

The best sources of vitamin C are fruits and vegetables, says Jerlyn Jones, a registered dietitian and owner of the Lifestyle Dietitian in Atlanta, and a spokesperson for the Academy of Nutrition and Dietetics. According to the NIH, the foods with the most vitamin C are:

• Oranges and grapefruit.
• Red and green peppers.
• Kiwifruit.
• Swiss chard.
• Broccoli.
• Cauliflower.
• Strawberries.
• Brussels sprouts.
• Cantaloupe.
• Cabbage.
• Baked potatoes.
• Tomatoes and tomato juice.

Because vitamin C enhances absorption of iron, which is found predominantly in plant-based foods, consider combining the two when you eat. "For example, tomatoes on your leafy green salad, or roasted broccoli with quinoa, would increase the absorption of iron at your meal," Farrell Allen says. In a similar vein, Jones tells her patients to drink half a cup of orange juice when taking their iron pills.

Vitamin C is also added to some processed foods, like fortified breakfast cereals. To find out if vitamin C has been added to a food product, check the product labels, Jones says.

Most people get enough vitamin C in their diets, the NIH says. Smokers are one exception, because the body needs more vitamin C to repair the damage caused by smoking. Those who live in disadvantaged "food desert" neighborhoods are another. Indeed, according to the Science History Institute, at least 30 cases of scurvy were reported between 2010 and 2015 in one of the poorest neighborhoods of Springfield, Massachusetts.

Vitamin C is also available in supplement form, with most multivitamins containing at least 100% of daily recommended levels. But food sources are always preferred to supplements for all vitamins and minerals. One caveat: Vitamin C is water-soluble and sensitive to heat. That means that boiling your broccoli or spinach reduces the amount of vitamin C by 50% or more. Roasting, steaming or microwaving are better cooking methods to retain this antioxidant. Eating them raw is even better, Jones says: "Easy and tasty snacks to try are red and green peppers dipped in hummus or plain Greek yogurt topped with fresh strawberries."

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