Saskia Reeves-Priestley collapses at work, discovers severe vitamin D deficiency

A 23‑year‑old special‑educational needs teacher collapsed at work after feeling dizzy, nauseous, hot and experiencing heart palpitations, and a blood test later showed her vitamin D level was “next to nothing”. Saskia Reeves‑Priestley, who also plays football four times a week, had never suspected a deficiency could cause such a dramatic episode.

Her story comes as the UK sees a sharp rise in low vitamin D levels among teenagers and young adults, especially girls and young women. The National Diet and Nutrition Survey found that almost a quarter of 11‑ to 18‑year‑olds were classified as deficient last year. The body makes most of its vitamin D when skin is exposed to sunlight, so shorter daylight hours, cloudy weather and indoor lifestyles cut production. Covering up with clothing or using sunscreen further reduces synthesis, and people with darker skin need more intense UV exposure to make the same amount as lighter‑skinned individuals. Diet alone rarely supplies enough; oily fish, meat and fortified foods help, but many young people still fall short.

Doctors do not routinely screen for vitamin D deficiency, but they will prescribe supplements if a patient is deemed at risk. The condition is often called “the silent disease” because its signs – fatigue, joint or bone pain, occasional shakiness – can be mistaken for other problems. Dr Suma Uday, a paediatric endocrinologist, warns that untreated deficiency weakens bones, leading to osteomalacia in adults and rickets in children. She cites another case of a 21‑year‑old university student who collapsed while cooking and was later diagnosed with the same deficiency. After starting supplements, the student reports feeling much better, but remains anxious about a repeat episode.

A coalition of clinicians and academics, including Dr Uday, has formed ACT NOW Vitamin D to push for a higher threshold for defining deficiency. Raising the cut‑off would capture more people who are low on the nutrient and allow earlier treatment. Health officials are being urged to update guidance, increase public awareness and consider routine testing for at‑risk groups. In the meantime, experts advise regular safe sun exposure, a diet that includes vitamin‑D‑rich foods, and supplementation where needed, especially during the darker months.