One navel orange contains 83mg of vitamin C and one half of a red grapefruit contains about 46mg. Both can go a long way in helping you meet the 75 to 90mg recommended daily.

Vitamin C plays an important role in your immune system, said Natalie Allen, a dietitian and clinical associate professor of nutrition at Missouri State University. The vitamin – considered an essential nutrient because your body can’t make it itself – helps to form the cells that make up your immune system, she said. It also aids those cells in locating and fighting infections.

Vitamin C contributes to wound healing and tissue growth, too, so it keeps your skin, muscles and blood vessels healthy, Allen said. And the nutrient helps your body absorb “non-heme iron,” which is iron from plant-based foods like lentils and spinach.

They won’t cure your cold, but they might shorten it

There’s no evidence that vitamin C can cure seasonal illnesses, said Alex Kojo Anderson, a professor of nutritional sciences at the University of Georgia.

“If you have a cold now and you take vitamin C, it’s not going to have much impact,” he said.

But regularly meeting your recommended daily dose of vitamin C (including on days when you’re healthy) can help your immune system do its job, which could shorten the length of a cold when you do get one. One 2013 meta-analysis found that consuming at least 200mg of vitamin C daily helped people kick the common cold about 8% faster.

The analysis focused on vitamin C from supplements, not from citrus fruits, but Anderson said it’s best to get your vitamin C through whole fruits. When you eat a whole fruit, you’re also getting other nutritional benefits – think gut-friendly fibre, hydrating water and other micronutrients – that you won’t find in powders, gummies or tablets.

They may help lower inflammation

Chronic inflammation can raise your risk of cancer, heart disease and diabetes. The vitamin C in citrus is an antioxidant that helps limit this inflammation, said Christiane Meireles, a dietitian and clinical associate professor in the School of Nursing at the University of Texas Health Science Center at San Antonio.

Citrus fruits also contain other compounds, like carotenoids, that may act as antioxidants. This adds to their anti-inflammatory benefits, Meireles said.

How to enjoy them

Choose oranges over OJ: Whole fruits are your best bet when it comes to maximising nutrients. When you juice a citrus fruit, you end up losing much of its beneficial fibre, Meireles said. And because it takes several pieces of fruit to produce a glass of juice, you typically consume more sugar and calories when you drink it.

Be wary of medication interactions: Grapefruit and grapefruit juice can interfere with some medicines by blocking an enzyme that helps metabolise certain drugs. As a result, more of the drug enters your bloodstream, increasing the risk of side effects. In other cases, including with common thyroid medications, grapefruit can have an opposite effect, blocking the drug’s absorption. If you take prescription medications, Allen recommended asking your doctor before consuming grapefruit.

Don’t ditch the peels: Some research suggests that the citrus oils in the peel’s outer layer contain their own antioxidants that may benefit your health, Meireles said. Adding citrus zest to a dish can help you tap these potential benefits.

This article originally appeared in The New York Times.

Written by: Caroline Hopkins Legaspi

Photographs by: Kelly Marshall, Christopher Testani, Monica Pierini

©2025 THE NEW YORK TIMES