GP urges everyone in Ireland to take 1 pill each day from nowA GP has urged people to take a key pill every day, and it's essential during the winter months to boost your immune system. What many don't realise is that vitamin D serves as a vital nutrient which supports strong bones, teeth and muscles by facilitating calcium and phosphorus absorption. Insufficient vitamin D levels can lead to skeletal issues including rickets in youngsters and osteomalacia in adults. ‌The Health Service Executive explains: "Everyone in Ireland needs to take a vitamin D supplement. "If you have dark skin – for example you have an African, African-Caribbean or south Asian background – you may also not make enough vitamin D from sunlight.