A new study finds that nearly a quarter of adults and teenagers and one in 10 children in the UK are not getting enough of one vital nutrient, vitamin C. The report, presented at the Nutrition Society’s winter conference at the Royal Society in London, found that millions of people in the UK are not consuming enough vitamin C.

The research analysed the UK government’s National Diet and Nutrition Survey and found ‘worryingly low’ intakes of vitamin C – an essential nutrient and antioxidant which protects body cells and boost immunity.

Vitamin C intakes were below recommended levels for 11% of children aged 1-10 years; 17% of those aged 11-14 years and 23% of those aged 15 years and older, according to the new research. It is the first time that vitamin C intakes have been reported for more than a decade.

The researchers say the UK-wide shortfall of vitamin C intake can be attributed to increased consumption of ultra-processed foods, including ready meals, frozen desserts and fizzy drinks. Data from the National Diet and Nutrition Survey has shown that over 65% of daily calorie intakes in adults and teenagers are made up of ultra-processed foods – which are likely to be low in nutrients, particularly vitamin C which is easily destroyed during food processing and storage.

Dietary analysis revealed that 100% fruit juice and smoothies are the primary sources of vitamin C, contributing to around 30% of total intake. Fruits account for 20% and raw vegetables 17%, while sugar-sweetened beverages, including fizzy drinks and cordials, provide 13%. Notably, cooked fruits and vegetables did not feature as key contributors, as vitamin C is diminished during prolonged cooking.

Study author, Dr Emily Royle, said: “The findings are a cause for concern, highlighting a gap in the consumption of vitamin C-rich foods. Despite the wide availability of these, there’s a clear deficit of vitamin C among UK residents, worsening with age.

“Only one in ten teenagers and a third of adults are eating the recommended 5-a-day of fruit and vegetables., Instead, they rely on alternative sources for their vitamin C such as fortified foods. A small glass of 100% orange juice fulfils the daily recommendation for children and adults and never contains added sugar, yet only a third of adults and half of children drink fruit juice regularly.

“Other surprising sources of vitamin C include Broccoli, with one serving at 80 grams containing over 100% of adults recommended daily intake [RDI], Spinach with an 80 gram portion of containing 47.5% of an adults RDI, and Lemon with one containing up to 75% of an adults RDI.

“Given vitamin C’s role in supporting immune health, it’s important that people boost their intakes of vitamin C-rich foods and beverages during winter and spring when colds and flu are rife.”

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